EuclidI don't think that crossing at right angles will necessarily solve the problem. Casters are squirrelly. They could hit the flangeway perpendicular to it and instantly flip around by 90 degrees and drop right into the flangeway.
One cure for this is to detent and spring the casters on any wheelchair so they take up fore-and-aft alignment if unloaded -- this might ease stowage and transport.
It occurs to me that far before explosive-bolt demountable casters begin to make sense, simple drop-in ramps combined with savvy wheel dimensioning and design might provide the necessary extraction assistance in many mishaps where merely lifting the chair out is not possible and no jacking capability is available. I think if you have differential drive motors this would always let you out.
I don't think that crossing at right angles will necessarily solve the problem. Casters are squirrelly. They could hit the flangeway perpendicular to it and instantly flip around by 90 degrees and drop right into the flangeway.
tree68I believe you could mass-produce signs that say "Cross Tracks at Right Angles" for under $20 each. Maybe include a simple graphic illustrating the concept. Might have to replace a sign from time to time. Problem solved.
A proper sign really has to add the important concern, which is "don't stop or try to turn around no matter what once you start across" (I'll let y'all figure out what that should be in terse English) perhaps with the added note "trains move faster than scooters and faster than they appear".
Keep in mind that we still might be able to lobby FRA for specific exemptions from the nothing-above-railhead mandate permitting 90-degree crossing 'rails' or even ribbing in the crossing plates to enforce wheels-straight...
Convicted One Euclid The solution is right there now, ready to purchase and install. It will probably make a profit with all the money the railroads will save in flangeway cleaning and prevented derailments Updating 3 million chairs has gotta be cheaper than retrofitting 20,000+ grade crossings
Euclid The solution is right there now, ready to purchase and install. It will probably make a profit with all the money the railroads will save in flangeway cleaning and prevented derailments
Updating 3 million chairs has gotta be cheaper than retrofitting 20,000+ grade crossings
I come up with $200,000,000. for the flangeway fillers with installation and $600,000,000 for the chairs. This is contingent on review of your ejection wheels drawings.
Convicted One If we could harness the creativity you expend in determining why potential solutions won't work, instead upon workable alternatives.....we might already be on the downhill side of this dilemma?
Standardize the ejectable wheels, and include a workable spare with each chair, such that there was a field expedient method of installing the spare after the incident?
Perhaps even add two wheels and mount the at-risk wheels in two-wheel span bolster type configuration, thus giving the operator "drive-off" capability for the initial escape?
Or alternately perhaps even installing a ball-and-socket 5th wheel centered between the two at-risk wheels that NORMALLY isn't in contact with the ground, only coming into service once one of the primary wheels had already been jettisoned? (to prevent the chair from bottoming out after the jettison)
I firmly believe that the correct solution will be one specific to the chair, not the grade crossing.
Updating 3 million chairs has gotta be cheaper that retrofitting 20,000+ grade grossings.
Retrofitting all Hoverounds to make them grade-crossing "friendly" is likely to require a change in the medical reimbursement that made so many of these chairs used in the first place (watch a Scooter Store ad carefully if you want details). This complicated by all the users who never go near a crossing, but smell class-action in the offing and request conversion of their unit plus perhaps damages for having sold them an unsafe and unsuitable product... (which of course it was, just not so much to them). The real issue is replacing every single caster and wheel assembly on every Hoveround, even the ones bought out of thrift stores or through private trades.
As Euclid points out, the cost to install flexible flange fillers in the sections of crossings that require them fir this purpose is likely not that great, nor is the cost of periodic replacement, or monitoring for damage or wear, on the part of railroads contracting with municipalities or states. I'd be prepared to see the cost of this as a legitimate crossing-safety line item for funding -- whereas fixing scooters in a non-bankrupting fashion involves just as much ultimate taxpayer "contribution", just more indirectly and not benefiting anyone but a select few scooter owners.
Having said this, a 'first best solution' is to implement the wider yokes and 'lifting-flank' tire profiles for casters I described, and make those mandatory for new manufacture and provide a 'retrofit kit' for older examples -- that just slots into the existing caster mount. This regardless of what people might do with grade-crossing-safety retrofitting in the field...
I believe you could mass produce signs that say "Cross Tracks at Right Angles" for under $20 each. Maybe include a simple graphic illustrating the concept.
Might have to replace a sign from time to time.
Problem solved.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
EuclidThe solution is right there now, ready to purchase and install. It will probably make a profit with all the money the railroads will save in flangeway cleaning and prevented derailments
OvermodThis would manifestly not work on a Hoveround, for a couple of fairly obvious engineering reasons. In the New Brunswick incident, jettisoning the 'anti-tip' apparatus might have allowed recovery, but there is no guarantee the chair would still be able to recover onto pavement, particularly if the battery charge were low; it would make no sense to jettison
If we could harness the creativity you expend in determining why potential solutions won't work, instead upon workable alternatives.....we might already be on the downhill side of this dilemma?
Regardless, I firmly believe that the correct solution will be one specific to the chair, not the grade crossing.
Updating 3 million chairs has gotta be cheaper than retrofitting 20,000+ grade crossings.
(I'm watching a James Bond marathon today, and I've gotta believe that "Q" could crack this nut )
The Pinto Principle would seem to apply here.
And - we've discussed this before with other issues - who is ultimately responsible? The encroaching municipality, or the railroad?
I would suggest that a bit of an impasse might well ensue. The municipality saying it's the railroad's responsibility, the railroad saying it's the municipality's responsibility, with the railroad ultimately saying if it's so dangerous, we'll just close the crossing.
Convicted One ...saving the users life while saving the taxpayer tens if not hundreds of billions of dollars? for a remedy that only scarcely would ever be needed?
...saving the users life while saving the taxpayer tens if not hundreds of billions of dollars? for a remedy that only scarcely would ever be needed?
The solution is right there now, ready to purchase and install. It will probably make a profit with all the money the railroads will save in flangeway cleaning and prevented derailments. The only issue I see is the care and attention to detail needed in the installation. This is evident in the manufactuer's installation video. I think neither the cities nor the railroads will want to make the required effort during installation, so trained, certified installers will needed. They will not only install correctly, but also install at less cost than the railroads or the cities.
The product is an idea who's time has come.
Convicted OnePerhaps a more practical solution might be to develop a "quick release" function for the wheels, so that in the rare occurrence where such a stranding actually happens, the chair operator can reach down and slide a lever, and jettison the stranded wheel,
I think the principal problem I have with the idea, though, is how you prevent unintended actuation of the 'quick disconnect', perhaps involving a failure under load. If a chair were to release a front wheel when 'raised and castering' (as described for a different Canadian incident) and the wheel were to drop out or jam, this might conceivably cause tip over and injury -- without much recourse in the subsequent court action for damages. There is also a fair history in aviation of issues like hands-free ejection seats or 'cutting off the wrong engine' that bode ill for user-controlled wheel release.
In the short run, I think the simplest correction for 'scooters' is to implement the kind of extended wheel and yoke I described. There are practical retrofit solutions for other power chairs along similar lines, one possibility being jacks that can lift a jammed wheel combined with an arrangement to rotate or lock the caster in a straight line or other angle to ensure it won't promptly low-center again. Another alternative would be an air-bag arrangement that would lift the vehicle to allow it to be laterally dragged free.
The arguments in Australia and other places that adding width to the wheels may not always be possible is a valid one, but it applies only very peripherally to Hoveround or other 'zero-turn' scooters, where the outside wheels are already reasonably fat and the 'casters' entirely under the skirt of the device at all times.
What i think is the 'ultimate' solution is to establish a better rule for crossings: make them clearly to cross rails at a right angle; clearly provide reflective stripes defining the path to follow, even in dark or rain for users without mandatory vision correction; do not tolerate masts or other equipment from one type of mandated protection from interfering with free passage on sidewalks. And, not incidentally, use the 2.75" 'close' or Euclid-style frying-pan fillers, or full fillers where agreeable, just in the pedestrian-crossing 1.5m or equivalent and, as at Ashland, try to ensure that falling off the outside is 'recoverable'.
Then establish a combination of funding sources and enforcement that gets that done ... and also establishes the necessary ADA or comparable waiver that allows crossings to be marked closed to certain types of traffic until remediated.
Something else that hasn't been discussed is a variant of the 'I've fallen and I can't get up' that would be able to send an unspoofable signal to an 'automated crossing' warning system along with whatever monitoring system it used. A proper camera system would rapidly identify a stuck wheelchair; the railroad would get highly specific warning of an issue (or recourse for a false alarm); appropriate dispatch of first response could be near-immediate. (Note the interesting Canadian discussion of cell-phone emergency calling...)
Perhaps a more practical solution might be to develop a "quick release" function for the wheels, so that in the rare occurrence where such a stranding actually happens, the chair operator can reach down and slide a lever, and jettison the stranded wheel, saving the users life while saving the taxpayer tens if not hundreds of billions of dollars? for a remedy that only scarcely would ever be needed?
EuclidHow many fatalties does it require to be concerned about it?
How many dragons did Don Quixote eventually slay?
As callous as I am sure that it sounds, there need be an acceptable level of risk.
And I just don't see the cost of retrofitting every grade crossing in America with your "frying pan" solution to be justfied by the handful of incidents that might be prevented.
OM: Thank you for stating that so succinctly. It bugs me also to have participated in a thorough discussion of this issue, only to have someone crudely call Bucky a whiner, all the while he proposes a problematic active system.
TrainsButSmallTrue, but this dude is whining about flangeways when there have been few or no cases involving flangeway fatalities, so realism isn't exactly the point.
I am not sure what saying 'few or no flangeway fatalities' is supposed to mean in the context of a thread about a "flangeway fatality" -- had he read the TSB report in the immediately preceding post, he would have learned the number for Canada alone to the report date (7) as well as a great deal of earlier recognition of and concern over the issue (much of which I had not been aware of). Note for example that in both the California and New Brunswick examples a stated likely cause was positioning the crossing-signal mast in the sidewalk; note also (with a nod to the Ashland grade-crossing discussion) that a safety device is what likely precluded the Canadian operator from reversing back to safety.
TrainsButSmall True, but this dude is whining about flangeways when there have been few or no cases involving flangeway fatalities, so realism isn't exactly the point.
True, but this dude is whining about flangeways when there have been few or no cases involving flangeway fatalities, so realism isn't exactly the point.
How many fatalties does it require to be concerned about it?
I went back and reviewed that video of the wheelchair stuck on the track in Lodi. Regarding the seeming lack of urgency on the part of the guy in the chair, I could not see his expressions because his face was intentionally obscured in the video. But it is striking just how close of a call this actually was. He cleared the train with only a second or two to spare. I have a feeling that his overall discomfort of this event will lead him to be in the news again.
Here is the TSB report of the similar wheelchair mishap in Canada. Crossing/wheelchair fatality in Canada with extensive details of historical record of such accidents and related safety measures:
https://www.tsb.gc.ca/eng/rapports-reports/rail/2016/r16m0026/r16m0026.html
In this case, two people were trying to get the chair and the victim off of the track, but failed. He was struck and killed and also one of the two rescuers was struck and badly injured. One point revealed in the report is just how heavy these powered wheelchairs actually are. They said that in the case of this accident in Canada, the chair and rider weighed about 500 lbs. This weight would certainly play a role in how tightly wheels might get jammed into a flangeway, and how much effort it would take to overcome the resistance of the jam plus the 500-lb. load of chair and rider.
I assume that getting the rider out of the chair would be readily achievable even if there is some kind of seat belt that would have to be released. But I wonder about rescuers being confused over the mission of getting the rider and the chair into the clear, versus just getting the rider into the clear and then going back for the chair if there is time.
To the point above about powered, automatic flangeway fillers:
I don’t think they are the answer, except maybe in the EU. For North American railroads, the fully developed solution already exists. It does not solve 100% of the multifaceted problem, but it prevents people in wheelchairs from getting killed. It is a simple product that will more than pay for itself by reducing liability. In addition, it will probably make a profit by reducing flangeway maintenance and the fouling of crossing ballast.
BaltACD Cost to design the system $$$$$. Cost to install the system $$$$$$$. Cost to maintain the system $$$$$$$$$$$$$$$$$$$$$$$$. Not PSR friendly.
Cost to design the system $$$$$. Cost to install the system $$$$$$$. Cost to maintain the system $$$$$$$$$$$$$$$$$$$$$$$$. Not PSR friendly.
I think you're underestimating the cost.... You also forgot liability.
Might make sense if the cost and liability was the responsibility of whoever owns the road crossing the railroad, but some very wamr places will freeze over before municipalities fork over the necessary funs to implement this.
Sidewalk drawbridge!!!
TrainsButSmallSolution: have flangeways closed via solenoids until a train approaches, then proceed to open them after the gates are fully in the closed position. This way, nobody will get stuck unless they venture onto the tracks while the gates are fully closed, at which point they were probably suicidal anyway.
Never too old to have a happy childhood!
Solution: have flangeways closed via solenoids until a train approaches, then proceed to open them after the gates are fully in the closed position. This way, nobody will get stuck unless they venture onto the tracks while the gates are fully closed, at which point they were probably suicidal anyway.
The “Grand Canyon” flangeway is intended to be a repository so large, that you don’t have to clean it out often. Like a landfill, it is the size that makes it practical. Also the capacity is aided in delaying cleanout by the natural decomposition of material deposited. Ice and snow melt and the resulting water disappears by runoff, evaporation, and percolation. Dirt washes out or settles deeply into the ballast. Trash rots away. So in that sense, the “Grand Canyon” flangeway is like a septic tank always digesting much of its contents.
The obvious problem with the jumbo flangeway is its hazards to pedestrians. But there is also a downside that harms the interest of the railroad. One reference cites the fact that this internal consumption of debris eventually finds its way into the track bed and fouls the ballast, which then impedes drainage and causes frost heave of the ballast under the crossing. This causes the track under the crossing misalign with the connecting track outside of the crossing, thus forming a derailment hazard at the crossing. So while jumbo flangeways offer some benefit, they are also slowly poisoning the crossing by fouling the ballast.
So when you greatly reduce the size of the maximum size flangeway, you reduce ballast fouling, but the flangeway has to be cleaned out more frequently because its storage capacity has been reduced. If it is not cleaned out frequently, the filling and packing with debris will eventually crowd out and lift the flanges to the point of derailment.
However, with the shallow flangeway rail seal, you attack the ice while it is thin, and you do so often. Every passing train cleans the flangeway.
If that 'you can't trap your foot in a frying pan' is original, you have a really good Lorenzo Coffin-style slogan in the making.
I base my assessment on the material in the shallow-flangeway crossings I've seen on the type of wear or damage patterns I see, which are highly typical of medium to high density polyethylene or similar material. That's not to say that others aren't rubber or elastomer of some kind, or that some may have Zectron-like elasticity in a butyl composition.
Note that all the 'Grand Canyon' flangeways I have seen are essentially self-cleaning in that they are massively open below the edge of the filler' pieces defining the edge of the flange space. The ones on the LIRR in East Hampton appear to be designed to clear dirt and snow out of the entire flangeway space to where it can spill or be compressed across the ties and cribs in the gauge space, much as parking-lot vaults quickly take even the most severe storm runoff and remove it from the driving surface and surface drainage. This limits the active trapping of both debris and frozen water to just the open-bottom space occupied by about a 1.5" slot 'open to below' with metal-defined edges both sides.
All this of course merely makes trapping of transverse wheels a near-certainty over a fairly large gathering angle, and the 'lack of a bottom' guaranteeing full insertion which, for bicycle wheels, near-guarantees both a nasty spill and considerable irreversible wheel damage without sufficient visual warning. It would be possible to mitigate some of this with a grid, rather than continuous, filler at shallow-flangeway depth, and preserve most of the self-cleaning action, but there might still be danger of entrapment and spill. Perhaps the answer is a meshwork 'FF" that would support larger-diameter wheels and perhaps even casters so that they will effectively 'climb' either edge of the flange space as they turn without catching, sufficiently below the railhead that only a small percentage of the flange actually causes deflection of it.
All this of course merely makes trapping of transverse wheels a near-certainty over a fairly large gathering angle, and the 'lack of a bottom' guaranteeing full insertion which, for bicycle wheels, near-guarantees both a nasty spill and considerable irreversible wheel damage without sufficient visual warning. It would be possible to mitigate some of this with a grid, rather than continuous, filler at shallow-flangeway depth, and preserve most of the self-cleaning action, but there might still be danger of entrapment and spill. Perhaps the answer is a meshwork 'FF" that would support larger-diameter wheels and perhaps even casters so that they will effectively 'climb' either edge of the flange space as they turn without catching.
+1
We are indeed focusing on two types flangeway devices. One of them is the flangeway filler (FF) that has to compress and rebound as it is contacted by the flanges. In effect, when there is no train passing, the flangeway is completely filled with a material that will support vehicles but compress to allow flanges to pass. As I mentioned, these seem to be widely accepted for transit lines, but have no chance of acceptance by heavy rail systems.
The other type of device is the SHALLOW FLANGEWAY RAIL SEAL (SFRS). This is to be distinguished from the basic RAIL SEAL which also has a flangeway, but it is deeper than the flangeway of the SFRS.
The basic RAIL SEAL is not intended to address the flangeway safety issue, but the SFRS is intended to add flangeway safety by making the flangeway as shallow as possible. The emphasis is on “Shallow.” The flangeway for SFRS is about 1.5” deep versus up to 8-9” deep for the deepest flangeways, including those without any RAIL SEAL device. The idea behind the SFRS is that you can’t get your foot stuck in a frying pan.
The most preferred approach would be to use the SFRS. It does not need to directly yield to the flange as the FF does. Although the industry is not satisfied with a flangeway that merely clears the flange. They want a lot of clearance. So they will at least be hesitant to approve the SFRS while completely rejecting the FF.
From what I gather, all three of these categories; FF, SFRS, and basic RS are all made of rubber and not polypropylene. This is because the resilience of rubber plays a role in all three device categories as follows:
For FF, the flangeway filler has to compress and rebound with the passage of flanges.
For SFRS, the flangeway floor has to compress and rebound if ice or dirt builds up on the floor and that layer then is contacted by the flange. If it does so, the flanges will clean the fouling layer out of the flangeway. It is the flexing action of the flangeway floor that bends and fractures the layer so the flanges can crush and eject it from the flangeway.
For the basic RS, the whole assembly has to compress like a rubber gasket upon installation in order to make a seal around the rail and keep dirt and water from getting under the rail and into the ballast.
If this self-cleaning of the flangeway is proven effective, this SFRS is a brilliant solution to the problem of flangeway cleaning and flangeway safety. Not only will this flangeway not derail trains, it may very well prevent derailments that might otherwise be caused by dirt or ice fouling of the flangeways.
But the industry has got to be convinced that they don’t need the Grand Canyon flangeway in order to hold dirt and ice in storage to prevent it from contacting the flange. Indeed, the Grand Canyon flangeway cannot be made self-cleaning, so it will always fill to the point where it must be cleaned of ice, or dirt as soon as these materials build to the point where they are contacted by the flanges.
So rather than having the Grand Canyon flangeway that provides the longest possible interval between manual cleanings, they can have the self-cleaning SFRS and not have the need for any manual cleanings at all. A need for manual cleanings can lead to derailments if not cleaned in time. A self-cleaning flangeway, with no need of manual cleanings, make derailments impossible.
Quite possibly and thanks for a cogent, yet thorough summary of the main types.
charlie hebdoIn terms of safety, I'm not sure the filler needs to come to the top of the railhead. Rather the ones I see (on a very busy heavy rail line) slant down, more or less parallel to the flange outline.
It is correct that this could be shy -- even an inch or two shy -- of being 'perfectly level' with the railhead; it is even relatively unlikely that the inch or two of ice or dirt that might accumulate in the resulting recess would pose much more derailment risk than similar accumulation in the flangeway of a crossing with the HDPE strip fillers.
It will literally take an act of Congress, or some scheme that caps or removes railroad liability for accidents related to or arising out of the full-height fillers, to get them established at crossings. I don't blame either the railroads or the AAR for fighting to ensure they stay out of becoming unfunded mandates or assumable risks for railroad companies.
I wonder if a 'transition' profile, an otherwise full-height filler with a groove in it corresponding in location and depth to what a locomotive would 'cut for itself' in fresh asphalt, would be more acceptable as an alternative?
It will literally take an act of Congress, or some scheme that caps or removes railroad liability for accidents related to or arising out of the full fullers, to get them established at crossings. I don't blame either the railroads or the AAR for fighting to ensure they stay out of becoming unfunded mandates or assumable risks for railroad companies.
charlie hebdo BaltACD Euclid ... However the rail transit industry apparently has accepted the concept and applied it on a widespread basis. Perhaps they may look at it differently than does the heavy rail industry because transit is public sector, and heavy rail is private sector. Rail Transit is not running 15K foot trains at 60 MPH. Derail a transit car or two is very different than derailing a freight train that can be hauling everything from 'air' to bulk commodities to methylethyldeath. Such a derailment can involve 30 - 60 or more cars. Given the weight similarity between most freight cars and transit, which is huge when loaded, the freight cars are even less likely to be derailed. Your argument is illogical contrafactual and an example of fear-mongering. Freight Ines have plenty of derailments and how many are caused by crossing impediments? Of course they do manage to collide with each other all over and still have time to hit vehicles and pedestrians at those pesky crossings.
BaltACD Euclid ... However the rail transit industry apparently has accepted the concept and applied it on a widespread basis. Perhaps they may look at it differently than does the heavy rail industry because transit is public sector, and heavy rail is private sector. Rail Transit is not running 15K foot trains at 60 MPH. Derail a transit car or two is very different than derailing a freight train that can be hauling everything from 'air' to bulk commodities to methylethyldeath. Such a derailment can involve 30 - 60 or more cars.
Euclid ... However the rail transit industry apparently has accepted the concept and applied it on a widespread basis. Perhaps they may look at it differently than does the heavy rail industry because transit is public sector, and heavy rail is private sector.
However the rail transit industry apparently has accepted the concept and applied it on a widespread basis. Perhaps they may look at it differently than does the heavy rail industry because transit is public sector, and heavy rail is private sector.
Rail Transit is not running 15K foot trains at 60 MPH. Derail a transit car or two is very different than derailing a freight train that can be hauling everything from 'air' to bulk commodities to methylethyldeath. Such a derailment can involve 30 - 60 or more cars.
Given the weight similarity between most freight cars and transit, which is huge when loaded, the freight cars are even less likely to be derailed. Your argument is illogical contrafactual and an example of fear-mongering.
Freight Ines have plenty of derailments and how many are caused by crossing impediments? Of course they do manage to collide with each other all over and still have time to hit vehicles and pedestrians at those pesky crossings.
As long as 'you and your device' are willing to accept total liability should your device cause a derailment and post a bond to cover the potential - have at it and have fun! $100M sound like a potentially adequate bond.
In terms of safety, I'm not sure the filler needs to come to the top of the railhead. Rather the ones I see (on a very busy heavy rail line) slant down, more or less parallel to the flange outline.
EuclidIt is not even remotely similar or even analogous to running over a tire with a train.
In practice, of course, tires use internal pressure in the chamber (which is why they're called 'pneumatic tires') and rely on controlled deformation in the side walls more then deflection in the tread. This was not entirely the case for the "Micheline" approach, which used controlled deflection of the tread to center and guide the wheel -- an approach that works well for short times even on modern tires, as a friend of mine who owned a '70s Chevy Nova found out: if the vehicle track measured across tire centers is the same as the gauge, and the tires are slightly deflated so the tread can become concave when loaded on a rail, a profound self-steering effect develops even up to high speed, similar to that of a coned wheel but acting in both directions and with built-in damping of oscillations. Michelin backed this up with a flange but with the assumption it would only be 'for emergencies' or when negotiating sharper curves, and had it worked dynamically in groups of eight or ten the way it did in theory, it might have revolutionized light vehicles on even fairly crappy jointed rail. In practice the things bounced like basketballs when excited by low joints, especially if there were a resonance in the suspension related to the 39' spacing (like that in the Alco Hi-Ads susceptible to harmonic rock).
Few of the actual effects in tires are common to actual crossing fillers, including those cited by Euclid. Nor, I think, is the material in current tire treads common to extruded fillers. However, bending stresses in the shapes shown in Euclid's reference material might be interesting in producing permanent deformation and stress-raised cracking if the material's glass transition is close to something that might be encountered environmentally... which is seen in [/quote]Nor is is similar to the o-ring failure on the Space Shuttle.[/quote]Of course it is, or rather would be if the crossing fillers, as in the Shuttle ring case, had the glass transition temperature set unfortunately high. Interestingly enough Morton Thiokol had foreseen this issue fairly carefully (as high, not low temperatures were the danger) and had a hard engineering note that UNDER NO CIRCUMSTANCES were the boosters to be flown under about 41 degrees ambient.
It was 21 when the politically-motivated Challenger launch was attempted.
Recently there was a discussion of the 614T testing conducted in the mid-80s for American Coal Enterprises, in which Ross recounted quite a bit of experience at -35F. One place you can bet ambient temperature will be effectively heat-sinked is in components in contact with continuous steel rail. That will be one sidewall of the 'chamber' form. It had better remain amorphous and fully elastic below that temperature range...
Incidentally the range of deflection is probably less that an inch, but it's closer to the gauge side of the rail than the center of the extrusion, so either the chamber has to be asymmetrical or the bending greater on the gauge-side wall. And the deflection is determined by the maximum tolerable under bicycle or wheelchair spot pressure -- or by keeping the section from deflecting measurably at all under that load -- preserving the lowest possible resistance to deflection that can be tolerated by those vehicles and their users.
I also find it almost imcomprehensible that the face of such a filler would support, let alone sustain, combustion from a source as small and transient as a cigarette butt (or, now perhaps as likely in California, a marijuana roach). Or in fact, given the mass in the bearing face and contact with the heat sink of the rail, that even pouring lighted gasoline on it in an accident would cause more than surface char damage. Of course, the world is full of idiot designers who might leave flame-retardancy out of their mixture or surface treatment ASSuming it couldn't possibly see heat sources in use...
EuclidYou must be referring to this from one of my posts on the previous page: Quote: “Tried multiple times & fails all the time...could only be used in warm weather states and cigarettes set the pliable flangeway filler on fire.” Rail seal products are made from thick rubber just like tires, and that is why tires have been tried multiple times and fail all the time because they can't be used in cold weather and cigarettes set them on fire.
Quote: “Tried multiple times & fails all the time...could only be used in warm weather states and cigarettes set the pliable flangeway filler on fire.”
Rail seal products are made from thick rubber just like tires, and that is why tires have been tried multiple times and fail all the time because they can't be used in cold weather and cigarettes set them on fire.
Yes, I was referring to your language following the quote you attributed to MC.
Your language appeared to be intentionally facetious, so I thought you might appreciate a similarly spirited reply.
The "normal" use of tires in which they are successfully applied being other than the application we are discussing here.
Sticking my head further in the barrel, It wouldn't surprise me that if a flangeway was filled with combustable material, and a wind-whipped cigarette butt ignited those materials, a fire sufficient to damage the elastomer in the flangeway might result.
It's not so much that you have a "burning gasket" as you might have a flame damaged gasket. One that might not stand up to mechanical abuse...just something to think about
Having personal experience with moving joints employing similar materials in both commercial buildings and parking structures, I can tell you from experience that this risk is genuine.
Euclid... However the rail transit industry apparently has accepted the concept and applied it on a widespread basis. Perhaps they may look at it differently than does the heavy rail industry because transit is public sector, and heavy rail is private sector.
My understanding is that both the SFRS and FF are in need of regulatory approval for use in heavy rail systems. I do not know where they are at in the process of approval, but the resistance is likely to be much greater with FF because it actually fills the flangeway, and must be compressed by the passing train.
However, I find no evidence that either product is being stopped by a failure to successfully perform their intended function. So I doubt that either flammability or temperature performance are practical obstacles to widespread use.
But apparently what is an obstacle is railroad industry resistance to the concept because it reduces the extra space around the actual flangeway envelope. Apparently, the industry completely rejects the FF out of fear that it could cause a derailment.
Convicted One Euclid It is not even remotely similar or even analogous to running over a tire with a train. I thought that the logic was roughly approximate to your submission that " tires have been tried multiple times and fail all the time because they can't be used in cold weather "
Euclid It is not even remotely similar or even analogous to running over a tire with a train.
I thought that the logic was roughly approximate to your submission that " tires have been tried multiple times and fail all the time because they can't be used in cold weather "
You must be referring to this from one of my posts on the previous page:
Quote:
“Tried multiple times & fails all the time...could only be used in warm weather states and cigarettes set the pliable flangeway filler on fire.”
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The word "Quote" at the start of the start of the part in red means the part in red is quoted from MC from around page 1 or 2.
I don't know whether it is accurate or not, but I doubt it. I have seen these products in photos and videos, and they look like very heavy rubber like that of rubber tires for cars and trucks. I do not see those tires being set afire from cigarettes. Nor do I see them being only useble in warm weather. Therefore, I don't believe the claim that these flageway products have never been made workable because of catching fire from cigarettes or not working in cold weather.
Convicted One Overmod I personally can't imagine any problem in developing a combination of face material, core foam, and blowing-agent compositions and pressures that would not produce a reliable, UV- and contaminant-resistant strip that would bottom-anchor to a "legal" HDPE or whatever flangeway bottom filler across the width of a crossing (with approach nose pieces either end) which would reliably compress away in flange contact but not substantially under transient bicycle content or even sustained contact by even suicide-minded scooter pilots. While Euclid's sources may be selective in addressing how they handle their materials selection and fabrication, I'm sure you looked at the illustrations that Euclid linked to. With the hollow cell that deforms under the weight of the rail wheel, but not under the weight of a scooter. I'd be really, truly amazed if someone could develop an elastomeric that would withstand thousands of cycles per week in freezing temperatures, for very long. Add to that, the material must remain rugged on hot summer days, that is going to be a pretty remarkable material.
Overmod I personally can't imagine any problem in developing a combination of face material, core foam, and blowing-agent compositions and pressures that would not produce a reliable, UV- and contaminant-resistant strip that would bottom-anchor to a "legal" HDPE or whatever flangeway bottom filler across the width of a crossing (with approach nose pieces either end) which would reliably compress away in flange contact but not substantially under transient bicycle content or even sustained contact by even suicide-minded scooter pilots. While Euclid's sources may be selective in addressing how they handle their materials selection and fabrication,
I'm sure you looked at the illustrations that Euclid linked to. With the hollow cell that deforms under the weight of the rail wheel, but not under the weight of a scooter.
I'd be really, truly amazed if someone could develop an elastomeric that would withstand thousands of cycles per week in freezing temperatures, for very long.
Add to that, the material must remain rugged on hot summer days, that is going to be a pretty remarkable material.
Regarding what I highlighted in red above:
The hollow cell deforms under the force of the wheel weight, but the range of deformation is limited to only the depth of the wheel flange, or about one inch. So the hollow elastomer form is compressed by the wheel load, but the deformation is stopped after progressing just one inch. And at that point, the hollow voids in the elastomer extrusion are not even fully collapsed.
So while the wheel weight load to the rail may be teens of tons, the actual loading to the elastomer flangeway filler may be only a few hundred pounds. And that loading is on the relatively compressible, hollow void structure within the extruded form of the flangeway filler.
It is not even remotely similar or even analogous to running over a tire with a train.
Nor is is similar to the o-ring failure on the Space Shuttle.
If you design it like a tire, it has to do what a tire does. Interestingly there is a long and fascinating history of various ultimately-defective attempts to get tires to run compatibly at high speed over jointed rail with self-guarding frogs, which does have technological solutions but not commercial ones.
Anyone who looks at this problem will comprehend that a single central chamber will not succeed under the multiple stressing conditions: the 'face' has one set of concerns, and the bearing foam in the core very different ones. That battle was partially fought and lost with foam-filled ag and off-road tires, but then fought and won with the last generation of run-flats in European practice.
In any case, much of the argument appears to be predicated on the quaint American notion that the actual filler to TOR needs to be the 'only' part of the whole solution, that it needs to be 'fire and forget' in deployment, and that it needs to be designed and placed to be permanent. None of my own designs (since I was about 16) have suffered from those misconceptions, and I would like to think that Euclid's discussed ones won't.
As previously noted, the highway authority and not the railroad is responsible for the whole cost of the filler system, whether or not they delegate its provision or maintenance to railroads. They are also responsible for periodic maintenance and its effective documentation, and timely forwarding if defects or impending/overt failure, as necessary; it is ridiculous to have a railroad mandated to do this system-wide when local resources can do it 'distributed' (and use a government, socially-funded, repository as a clearinghouse both for information and cumulative data storage)
In my designs at least the 'face' is not continuous: there are periodic screw attach points molded 'through' that are overdesigned not to be fatigue or exposure fail points, and the strip is held to the underlying HDPE or whatever with security screws in addition to aggressive assisted with surface activation. Removal is relatively simple; replacement either taps back into existing holes or, with only slight and logically-understandable 'displacement' along the flangeway, self-tapped into new areas of HDPE. If you make the core foam a highly contrasting color, or put in material that visibly extrudes colored indicator through any crack or candalism damage, even casual inspection by town employees or an 'informed' public will give perfectly adequate warning of a need to repair or replace.
OvermodI personally can't imagine any problem in developing a combination of face material, core foam, and blowing-agent compositions and pressures that would not produce a reliable, UV- and contaminant-resistant strip that would bottom-anchor to a "legal" HDPE or whatever flangeway bottom filler across the width of a crossing (with approach nose pieces either end) which would reliably compress away in flange contact but not substantially under transient bicycle content or even sustained contact by even suicide-minded scooter pilots. While Euclid's sources may be selective in addressing how they handle their materials selection and fabrication,
Overmod Convicted One Take two identical rubberbands. Put one in the freezer over night, and then compare the two the following morning. Or for that matter use certain common O-rings...
Convicted One Take two identical rubberbands. Put one in the freezer over night, and then compare the two the following morning.
Or for that matter use certain common O-rings...
For those who may not remember:
https://www.youtube.com/watch?v=raMmRKGkGD4
Greetings from Alberta
-an Articulate Malcontent
Convicted OneTake two identical rubberbands. Put one in the freezer over night, and then compare the two the following morning.
Seriously, the reason MC is 'important' here is not because of some appeal-to-authority fallacy but because he knows the law and others don't. That counts for a great deal more than an acquired knowledge of advanced polymer chemistry and preparation.
One might as gainfully read John White's description of rubber car springs from even the era before 1834 ... which neatly contains all the pratfalls so far named in this thread ... and then look at the solutions for air-suspension bag springs and rubber isolators and snubbe in the railroad industry in the past half-century or so.
I personally can't imagine any problem in developing a combination of face material, core foam, and blowing-agent compositions and pressures that would not produce a reliable, UV- and contaminant-resistant strip that would bottom-anchor to a "legal" HDPE or whatever flangeway bottom filler across the width of a crossing (with approach nose pieces either end) which would reliably compress away in flange contact but not substantially under transient bicycle content or even sustained contact by even suicide-minded scooter pilots. While Euclid's sources may be selective in addressing how they handle their materials selection and fabrication, it should not be difficult to evolve a standards-type set of test requirements for a 'safe' device of the kind, which would suit agencies and Congressional committees well enough to "harmonize" the law with certain perceived 'social' improvements...
EuclidRail seal products are made from thick rubber just like tires, and that is why tires have been tried multiple times and fail all the time because they can't be used in cold weather
Run over an automobile tire with a 100 car loaded coal train, and then (try to) put it on your car and drive with it.
And then do the same thing with a tire that has sat outside over night at 20 degrees below zero, and note the difference.
As bad as the first tire is, the second will be far worse.
Take two identicle rubberbands. Put one in the freezer over night, and then compare the two the following morning.
tree68 charlie hebdo I strongly believe that trained and experienced experts' opinions are generally the ones that take precedence That's why we tend to take MC's word for it.
charlie hebdo I strongly believe that trained and experienced experts' opinions are generally the ones that take precedence
That's why we tend to take MC's word for it.
And that's why you snipped and pasted only the first part of my comment and ignore the posts of Euclid. No one is infallible and we all have an axe to grind: myself, you and MC, though he is the only one with a stake in the game.
charlie hebdoI strongly believe that trained and experienced experts' opinions are generally the ones that take precedence
Euclid SD70Dude charlie hebdo Perhaps you should ask MC (or whoever said that) why he posted an unsubstantiated opinion as though it were an established fact? It is well known that MC has a job involving track maintenance. By the sounds of it he had some first-hand experience with the stuff. If cigarette butts set it on fire, what the heck is it made of? Nitrate film!? Quote: “Tried multiple times & fails all the time...could only be used in warm weather states and cigarettes set the pliable flangeway filler on fire.” Rail seal products are made from thick rubber just like tires, and that is why tires have been tried multiple times and fail all the time because they can't be used in cold weather and cigarettes set them on fire.
SD70Dude charlie hebdo Perhaps you should ask MC (or whoever said that) why he posted an unsubstantiated opinion as though it were an established fact? It is well known that MC has a job involving track maintenance. By the sounds of it he had some first-hand experience with the stuff. If cigarette butts set it on fire, what the heck is it made of? Nitrate film!?
charlie hebdo Perhaps you should ask MC (or whoever said that) why he posted an unsubstantiated opinion as though it were an established fact?
Perhaps you should ask MC (or whoever said that) why he posted an unsubstantiated opinion as though it were an established fact?
It is well known that MC has a job involving track maintenance. By the sounds of it he had some first-hand experience with the stuff.
If cigarette butts set it on fire, what the heck is it made of? Nitrate film!?
I strongly believe that trained and experienced experts' opinions are generally the ones that take precedence. But sometimes well-meaning folks are so entrenched in their positions that they can't accept change and can only make rather silly. comments.
BaltACD charlie hebdo Perhaps you should ask MC (or whoever said that) why he posted an unsubstantiated opinion as though it were an established fact? Salesmen for products make many 'claims of fact' (their words) about their product - real world experience with those products in many cases refute those 'facts' and change them to bald faced lies. As in everything involving humanity - buyer beware.
Salesmen for products make many 'claims of fact' (their words) about their product - real world experience with those products in many cases refute those 'facts' and change them to bald faced lies. As in everything involving humanity - buyer beware.
Sure there are bogus products that are marketed as lies. But this rail seal line of products seems to be in widespread use with extremely clear videos and illustrations explaining the purpose and installation details. There are also many posted photographs of them installed on active grade crossings. They are manufactured by companies that make other railroad related products. And the explanations of how they work is not at all hard to believe or comprehend.
So when somebody says this, it does not seem to fit the pratical reality:
I don't doubt that there were trials and failures. Temperature performance of the rail seal material was probably tested extensively to get it to work with all conditions. But I doubt that temperature and cigarettes were a showstopper as the above comment implies.
charlie hebdoPerhaps you should ask MC (or whoever said that) why he posted an unsubstantiated opinion as though it were an established fact?
Paul of Covington charlie hebdo Bucky: That makes a lot of sense to me, as an amateur. I wonder what the real objections would be? Cost? Maintenance? Arrogance of ownership? This was Mudchicken's answer back in the first wheelchair thread on Aug 14: Paul of Covington mudchicken Mod: anything placed above the top of rail is a bozo no-no. (FRA/CaPUC/AREMA)....the same goes for any striping in the foul zone How about filling the gaps with something resilient that would support the weight of people but squish down under the rail traffic? I seem to remember seeing that somewhere, but I'm trying to remember where. Maybe it was streetcar tracks. Tried multiple times & fails all the time...could only be used in warm weather states and cigarettes set the pliable flangeway filler on fire. FRA flangeway rules needed a special exemption before the stuff was used. ______________ (edit): I tried copying the post and pasting it here. It may not be obvious, but the last reply is Mudchicken's answer. Here is the thread: http://cs.trains.com/trn/f/111/t/283776.aspx
charlie hebdo Bucky: That makes a lot of sense to me, as an amateur. I wonder what the real objections would be? Cost? Maintenance? Arrogance of ownership?
Bucky: That makes a lot of sense to me, as an amateur. I wonder what the real objections would be? Cost? Maintenance? Arrogance of ownership?
This was Mudchicken's answer back in the first wheelchair thread on Aug 14:
Paul of Covington mudchicken Mod: anything placed above the top of rail is a bozo no-no. (FRA/CaPUC/AREMA)....the same goes for any striping in the foul zone How about filling the gaps with something resilient that would support the weight of people but squish down under the rail traffic? I seem to remember seeing that somewhere, but I'm trying to remember where. Maybe it was streetcar tracks.
mudchicken Mod: anything placed above the top of rail is a bozo no-no. (FRA/CaPUC/AREMA)....the same goes for any striping in the foul zone
How about filling the gaps with something resilient that would support the weight of people but squish down under the rail traffic? I seem to remember seeing that somewhere, but I'm trying to remember where. Maybe it was streetcar tracks.
Tried multiple times & fails all the time...could only be used in warm weather states and cigarettes set the pliable flangeway filler on fire. FRA flangeway rules needed a special exemption before the stuff was used.
______________
(edit): I tried copying the post and pasting it here. It may not be obvious, but the last reply is Mudchicken's answer. Here is the thread:
http://cs.trains.com/trn/f/111/t/283776.aspx
A “rail seal” is comprised of two slightly different rubber extrusions, each placed against the side of the rail in a grade crossing. The difference in the two extrusions is that the one on the gage side of the rail contains a flangeway as part of the extrusion, and other one on the field side of the rail has its top surface flush with the top of the rail head.
The main purpose is to seal the rail against intrusion of water, snow, dirt, and trash, which otherwise can get under the rail and into the ballast, which then can foul the ballast and impede drainage. So a rail seal is basically a rubber gasket.
As a train passes over a crossing, there is often up and down movement of the rail bed as the crossing bed remains stationary. The flexible nature of the rubber rail seal accommodates the track movement while maintaining a tight seal between the moving rail and the stationary crossing bed.
In my most recent post just above, I described two products capable of reducing the flangeway hazard. One is the SHALLOW FLANGEWAY RAIL SEAL. As I understand it, this is a rail seal with the shallowest flangeway that will not interfere with the flange. As I understand it, this SFRS is just now being introduced, and may need regulatory approval.
The other of the two products I am describing is what I call a FLANGEWAY FILLER (FF). As I understand it, the FF is not approved for use in heavy rail system grade crossings, but only used for transit rail crossings.
Therefore, the main product that promises to be the solution to flangeway dangers of heavy rail systems is the SHALLOW FLANGEWAY RAIL SEAL. It differs from the basic rail seal by having a shallower and wider flangeway than does the basic rail seal.
I find nothing to verify that assertion quoted above that says about these rail seal products that they have been:
These products are being manufactured and sold, and seem to be in widespread use. The SHALLOW FLANGEWAY RAIL SEAL may not be in use, but it is just a new version of the basic RAIL SEAL, and they use the same pliable rubber material as will the SHALLOW FLANGEWAY RAIL SEAL. So what is it exactly that has been “tried many times and fails all the time” ?
Yeah, that covers it. As Don Oltmann has said about rail culture. "We don't it that way because we've always done it that way." And the corollary: "Any idea to the contrary? Wrong!!!"
_____________
"A stranger's just a friend you ain't met yet." --- Dave Gardner
The alternative concept to the SHALLOW FLANGEWAY RAIL SEAL (SFRS) is the FANGEWAY FILLER (FF). With FF, when no train is passing, the flangeway is 100% filled, flush with the crossing surface and rail head. In effect, there is no flangeway when no train is passing. So bicycles and wheelchairs will be unaffected by a flangeway.
However, the flangeway filler is resilient, so as a train passes, its flanges can depress the filler and make room for its flanges to pass. After a flange passes, the filler rebounds to its normal full elevation. This depress-and-rebound action occurs with the passage of each wheel. Because the train is so much heavier than road vehicles and further concentrates that weight onto each flange, the train will be able to depress the flange filler material, whereas road vehicles will not compress it at all. With so much weight difference to work with, the train flanges will be able to completely depress the filler with no chance at all of lifting the wheels off of the rail and thus disengaging a flange.
Therefore, regarding any goal of a “perfect” solution, the FF is closer to perfection than is the SFRS. The main difference is that FF prevents the flangeway from catching a bicycle wheel and causing it to run in the flangeway and thus veer off track to the course of the bicycle. The SFRS cannot eliminate this danger to bicycles, but it does eliminate the danger of bicycles getting a wheel stuck in a flangeway. So the only remaining part of the hazard is to pedestrians stepping on the rail, which is the smallest component of the overall hazard involving pedestrians on foot, on bicycle, or in wheelchair.
From what I gather, FF is widely used and accepted for transit railroads but not for heavy rail freight railroads. One reason given is that freight trains are too heavy for the filler material, and this quickly wears out the filler. However, this seems like nonsense because freight trains or transit trains can only depress the filler to the depth of their flanges, and both do so easily with their inherent weight, so there is no way a freight train can harm the flange filler that cannot be harmed by a transit train.
So, I assume the actual reason is that the railroad industry cannot countenance the idea of closing the flangeways at crossings and then forcing the trains to open them in order to pass. This rejection of the principle may be based on the practical experience of flangeways getting filled with dirt or ice to the point where opening them with a train is not 100% feasible. Flangeways filled with ice or dirt are known to derail trains. So, apparently the common thinking is that flangeways must be kept clear out of respect to the flange.
But flangeway fillers are not dirt or ice, and they have been proven to reliably yield to the weight of transit trains, so why can’t they do likewise with freight trains? If there is a practical reason, I have not heard it. But perhaps the cultural reason is enough to prevent flangeway fillers to be used for freight trains.
In any case, SFRS minimizes the flangeway size to the point of being practically safe without obstructing any of the flange path. However, it does reduce the respect to the flange by reducing the margin of extra space in the flangeway. That extra space is used to accommodate ice and dirt entering the flangeway before it accumulates to the poing of fouling the the actual flange path. So the extra space in the flangeway buys time before ice melts or dirt needs to be removed. With the SFRS, any accumulation of ice or dirt immediately fouls the flange path. So, for that reason, the SFRS appears to be a non-starter.
But there is another side of the coin with this issue. Ice fouling is much more common than dirt fouling. Dirt fouling has practical solutions that can eliminate the occurrence. But ice fouling is part of weather. The only way to eliminate it would be to heat the crossing. But here is the key. With the SFRS, ice fouling begins immediately upon formation of ice. There is no extra space in the flangeway to fill with ice before fouling the flange path. So ice will begin flange contact once it fills the flangeway to say ¼ inch above the flangeway floor.
Ice is brittle and the flangeway floor of SFRS is somewhat flexible even though it is not made to yield to flange interference as is the case with the Flangeway Filler (FF). When the ¼ inch of ice buildup on the SFRS floor reaches the height of the flange tip, the flange will depress the ice layer which is supported on a flexible floor of the SFRS. This interfering flange contact will depress the ice layer as it also bends it, thus causing it to easily fracture and disintegrate. So the shattered ice layer will be ejected from the flangeway by the passing flanges. This effect of immediately clearing ice from flangeways will also apply to clearing dirt. Either material will be cleared by the flanges because the clearing begins when the layer of the interfering material is very thin and supported on a flexible floor of the flangeway.
Therefore, while there is a customary belief that flangeways need extra space to hold debris while provding clearance to the flange; there is a counterpoint that eliminating the extra space makes the flangeway self-cleaning.
Convicted One BaltACD .Ah yes - The disabled need to be vetted, supervised and trained more effectively. From the post you were responding to: Perhaps better vetting of caregivers is an answer?
BaltACD .Ah yes - The disabled need to be vetted, supervised and trained more effectively.
From the post you were responding to: Perhaps better vetting of caregivers is an answer?
In as much as the incident that has generated this thread was from a diabled individual without caregiver - it applies to the disabled individual.
EuclidElimination of the flangeway hazard can only be accomplished by perfecting a safe flangeway or developing an entirely different wheelchair.
Have to be mindful that the expense of reaching perfection does not exceed the cost of the risk.
As in so many of these type discussions, a train runs over a conductor, so "we" embark upon devising a ruleset so strenuous that such occurance can NEVER HAPPEN AGAIN, ..or an engineer is found intoxicated on thejob, so "we" attempt to design a system so elaborate that any engineer will be unable to start his locomotive without satisfying a lockout device.
And now here we are designing the "perfect" handicap grade crossing appliance?
I supect that the principle of diminishing returns need neccessarily factor into these deliberations, where we recognize that reaching a reasonable level of protection is worthwhile, whereas expecting "perfection" is a folly.
BaltACD.Ah yes - The disabled need to be vetted, supervised and trained more effectively.
Convicted One Euclid Such a law would require that the wheelchair user be tested for their ability to get out the chair and into the clear in time. I don't believe that is gonna happen. The whole ADA thing is about freeing the disabled to become independant by removing barriers. They aren't IMO going to add a layer of restriction. It would be seen as a step backwards. One would think that any chair-bound individual who was unable to enter and exit the chair on their own would have a care giver. And it does seem questionable that a responsible caregiver would allow such a person to go out in public unattended. Perhaps better vetting of caregivers is an answer?
Euclid Such a law would require that the wheelchair user be tested for their ability to get out the chair and into the clear in time.
I don't believe that is gonna happen.
The whole ADA thing is about freeing the disabled to become independant by removing barriers. They aren't IMO going to add a layer of restriction. It would be seen as a step backwards.
One would think that any chair-bound individual who was unable to enter and exit the chair on their own would have a care giver. And it does seem questionable that a responsible caregiver would allow such a person to go out in public unattended. Perhaps better vetting of caregivers is an answer?
Ah yes - The disabled need to be vetted, supervised and trained more effectively.
The stark reality of this situation is that, depending on the crossing flangeways, a wheelchair rider may become locked into a position where it is impossible to yield to a train, and it will also impossible for the train to yield to the wheelchair rider. Even if a rider is extremely careful, it is too much of a risk. I cannot think of another traffic situation that is comparable. The accommodation in this case can only be the elimination of the flangeway hazard. Otherwise the crossing has to either be closed to wheelchairs or closed to trains.
Elimination of the flangeway hazard can only be accomplished by perfecting a safe flangeway or developing an entirely different wheelchair. It would not be safe enough to allow cars and trucks to pass over a grade crossing if there was no possibility of the drivers to extricate themselves from their vehicles.
EuclidSuch a law would require that the wheelchair user be tested for their ability to get out the chair and into the clear in time.
Something the Canadian accident demonstrated rather dramatically is, as with some firearm trauma, even just contact with the train will produce immediate damage. The inertia of the woman's arm was enough to cause the loss of her hand.
A key phrase in the ADA is "reasonable accomodations", which implies that the accomodations should not adversely affect safety. For example, how many airliners are equipped to handle motorized wheelchairs in the cabin?
Another question is who pays for the installation and maintennance of these accomodations?
EuclidI too noticed that the person in the trapped wheelchair seemed unalarmed as the train was approaching. I want to review that video again. It poses the question of what such a person might do to evade the train.
Or, at minimum,.. assist the police officer trying to rescue them. Doesn't appear to be one stitch of cooperation there. And that one fleeting glimpse we get of the person's face, didn't really look like an expression of enthusiasm.
That last comment is perhaps unfair, because I have no way of knowing what's going on in the person's mind. But I know that if it was me in that position, I'd be overflowing with gratitude.
We'll never know.
Euclid... Such a law would require that the wheelchair user be tested for their ability to get out the chair and into the clear in time. If they cannot do that and require the assistance of others, those people would be tested for their ability to assist the wheelchair user in case of getting the wheelchair stuck in grade crossing flangeways. In that crossing death of a wheelchair user in Canada, that I posted earlier, there were two other people working together to get the wheelchair unstuck or get the person out of the chair and into the clear. They failed to accomplish that and the person in the chair was killed. Also, one of the two helpers was struck by the train and injured in the attempt to rescue the person in the wheelchair.
Such a law would require that the wheelchair user be tested for their ability to get out the chair and into the clear in time. If they cannot do that and require the assistance of others, those people would be tested for their ability to assist the wheelchair user in case of getting the wheelchair stuck in grade crossing flangeways.
In that crossing death of a wheelchair user in Canada, that I posted earlier, there were two other people working together to get the wheelchair unstuck or get the person out of the chair and into the clear. They failed to accomplish that and the person in the chair was killed. Also, one of the two helpers was struck by the train and injured in the attempt to rescue the person in the wheelchair.
Just what is needed - a 'Wheelchair License'. [/sarcasm] Since we are in a Covid-19 world, should 'the authorities' issue a 'Breathing License'?
I too noticed that the person in the trapped wheelchair seemed unalarmed as the train was approaching. I want to review that video again. It poses the question of what such a person might do to evade the train.
I assume that people using wheelchairs may have some bodily mobility in their limbs that might enable them to get out of the chair and clear of the track. I also assume that some people are so disabled that getting out of the chair and into the clear would be absolutely impossible. If this is the case, it is too dangerous to allow them to pass over a railroad grade crossing without the assistance and protection of one or more able bodied persons.
Otherwise, if they are incapable of exiting the chair and moving themselves into the clear, and considering that it is impossible for the train to yield in many cases, crossing the track in a wheel chair is a risk that should be legally prohibited. It is a known and demonstrated fact that wheel chairs can and do get stuck in crossing flangeways.
Euclid. This patent reduces that maximum flangeway depth to about 1 inch. The width appears to be about 2.5” maximum. And there is some angular and fillet radius easing of the flangeway wall opposite the flange.
Well, I certainly wish them well. Finding a material that is resilient at 120 degrees, as well as -20 degrees.......that is also impervious to UV degradation, I expect will be challenging. And then you throw in 10,000 wheelsets passing per week...I expect maintenance will be important.
I looked at the crossing on the UP mainline today. It is flush with the railhead on the outside, depressed somewhat, then slanting up on flangeway . You can even see where a flange on a heavy car that bounced left a depression. Seems safe for all. But I don't know the maker.
charlie hebdo Euclid Open this link to the patent on SHALLOW FLANGEWAY RAIL SEAL. https://patents.google.com/patent/US20120000987 Below the abstract are 8 illustrations. Open the one nearest the left side of the page. That is image 1 of 8. The other images show various separate details, but image 1 shows everything assembled with all detail shown. The image can be blown up to very large size if necessary. The main point is that it is not the width of the flangeway that is the safety issue for small wheels. It is the depth that is the issue. Much current practice is a flangeway that is the full height of the rail, such as maybe 8-10 inches. This patent reduces that maximum flangeway depth to about 1 inch. The width appears to be about 2.5” maximum. And there is some angular and fillet radius easing of the flangeway wall opposite the flange. It seems to me that casters of wheel chairs could be forced to climb out of this flangeway. Because the flangeway is so shallow, it does not need a lot of width to allow the caster to turn on its swivel. With a 6” caster wheel dropping into a 1” deep flangeway, the caster would probably be able to pivot say 45 degrees before it encountered any interference with the flangeway sides. Also, wheel chair wheels could probably be design optimized to ideally interact with these new shallow flangeways. Altogether, I believe this new shallow flangeway coupled with improved wheel chair wheels completely solves the wheelchair problem for grade crossings. What is does not solve completely is the ability to catch and track a bicycle wheel off its course and cause the bicycle to tip over sideways. It also does not prevent pedestrians from stepping on a rail. Seems pretty good.
Euclid Open this link to the patent on SHALLOW FLANGEWAY RAIL SEAL. https://patents.google.com/patent/US20120000987 Below the abstract are 8 illustrations. Open the one nearest the left side of the page. That is image 1 of 8. The other images show various separate details, but image 1 shows everything assembled with all detail shown. The image can be blown up to very large size if necessary. The main point is that it is not the width of the flangeway that is the safety issue for small wheels. It is the depth that is the issue. Much current practice is a flangeway that is the full height of the rail, such as maybe 8-10 inches. This patent reduces that maximum flangeway depth to about 1 inch. The width appears to be about 2.5” maximum. And there is some angular and fillet radius easing of the flangeway wall opposite the flange. It seems to me that casters of wheel chairs could be forced to climb out of this flangeway. Because the flangeway is so shallow, it does not need a lot of width to allow the caster to turn on its swivel. With a 6” caster wheel dropping into a 1” deep flangeway, the caster would probably be able to pivot say 45 degrees before it encountered any interference with the flangeway sides. Also, wheel chair wheels could probably be design optimized to ideally interact with these new shallow flangeways. Altogether, I believe this new shallow flangeway coupled with improved wheel chair wheels completely solves the wheelchair problem for grade crossings. What is does not solve completely is the ability to catch and track a bicycle wheel off its course and cause the bicycle to tip over sideways. It also does not prevent pedestrians from stepping on a rail.
Open this link to the patent on SHALLOW FLANGEWAY RAIL SEAL.
https://patents.google.com/patent/US20120000987
Below the abstract are 8 illustrations. Open the one nearest the left side of the page. That is image 1 of 8. The other images show various separate details, but image 1 shows everything assembled with all detail shown. The image can be blown up to very large size if necessary.
The main point is that it is not the width of the flangeway that is the safety issue for small wheels. It is the depth that is the issue. Much current practice is a flangeway that is the full height of the rail, such as maybe 8-10 inches. This patent reduces that maximum flangeway depth to about 1 inch. The width appears to be about 2.5” maximum. And there is some angular and fillet radius easing of the flangeway wall opposite the flange.
It seems to me that casters of wheel chairs could be forced to climb out of this flangeway. Because the flangeway is so shallow, it does not need a lot of width to allow the caster to turn on its swivel.
With a 6” caster wheel dropping into a 1” deep flangeway, the caster would probably be able to pivot say 45 degrees before it encountered any interference with the flangeway sides.
Also, wheel chair wheels could probably be design optimized to ideally interact with these new shallow flangeways.
Altogether, I believe this new shallow flangeway coupled with improved wheel chair wheels completely solves the wheelchair problem for grade crossings.
What is does not solve completely is the ability to catch and track a bicycle wheel off its course and cause the bicycle to tip over sideways.
It also does not prevent pedestrians from stepping on a rail.
Seems pretty good.
Yes, I think that if that Shallow Flangeway Rail Seal were installed in the flangeways of a crossing, no existing wheelchair could get stuck in a flangeway of that crossing. Even that wheelchair shown in Balt's post on the previous page would not get stuck in a flangeway that was equipped with the Shallow Flangeway Rail Seal. The product solves 100% of the problem for wheelchairs.
The only problem is that, as I understand it, the product is not yet approved for use. Such approval will require extensive testing, not only for the passage of wheelchairs, but also for the ability of passing trains to demonstrate a reliable ability for the Shallow Flangeway Rail Seal to be self-cleaning of ice frozen into the flangeway. If that is proven to be successful, not only will the crossing be safer for pedstrians, but it will also require less maintenance.
Overmod The AARP 'chair' pictured a few posts up would need more substantial redesign for safe structural integrity, but that is laughably far from a true zero-turn 'mobility' scooter...
There is no doubt a considerable inventory of chairs already in use that would, IMO, present problems in modifying. So I envision a plethora of "bolt on" upgrades, that likely would widen the track of the chairs.
And I already get "clipped" from time to time as I am picking merchandise off bottom shelves in stores, without so much as an "excuse me" from the chair operator, so I must insist upon seeing such upgrades as potentially making a bad situation worse.
You might think that risk to be unlikely, but my local library has actually thrown out a couple users for their serial disregard for the patrons around them....
Convicted OneI suppose you could put tires on all chairs that are sufficiently sized to prevent this problem, but then you are going to create other problems such as clearances in grocery store aisles, and such.
Widening both caster wheels on the other hand involves no external clearance issues at all; they are internal to the horizontal 'envelope' of the machine. The AARP 'chair' pictured a few posts up would need more substantial redesign for safe structural integrity, but that thing is laughably far from a true zero-turn 'mobility' scooter...
Widening both caster wheels on the other hand involves no external clearance issues at all; they are internal to the horizontal 'envelope' of the machine. The AARP 'chair' pictured a few posts up would need more substantial redesign for safe structural integrity, but that is laughably far from a true zero-turn 'mobility' scooter...
charlie hebdoAre you saying the guy in the video was faking?
What was actually at the core of my thought process was, the only thing I can imagine that would be more embarrasing than killing ones self, would be to try, and fail. So, I believe that some people actually go an extra step to make their planned departure appear accidental.
I don't propose to know that was this individual's plan. But I know if I was in his predicament and was not intent upon ending it all, I'd be doing considerably more to try and capture someone's attention (a motorist, perhaps) than it appears he was doing in the video. Flailing arms....even go so far as to topple myself out of the seat and drag myself with my arms to a distance.
And it didn't appear to me that the guy was doing any of that. So, absent tangible evidence to the contrary, my answer to your question would be "can't rule that out"
And, how that keys into the conversation, I do not believe it is possible to design a "same grade" solution to this problem that would prevent a determined person from succeeding.
I suppose you could put tires on all chairs that are sufficiently sized to prevent this problem, but then you are going to create other problems such as clearances in grocery store aisles, and such.
Jumps right out at you that in 1998 nobody had a clue about Hoveround zero-turn power-chair entrapment issues. Be interesting to run this and the other incidents past those people and see how their opinions would change!
"The Americans with Disabilities Act (ADA) requires that public buildings provide harrier-free access to mobility impaired individuals and may apply to grade crossings in areas where such individuals are likely to require access. The Architectura.l and Transportation Compliance Board has proposed standards, not yet officially adopted, setting Out minimum requirements for new construction of public sidewalks over railroad tracks. Among other things, the standards specify that the public sidewalk surface must be level and flush with the rail top at the outer edge and between the rails, with a horizontal gap on the inner edge of each rail (necessary to allow passage of rail-vehicle wheel flanges) not exceeding 2.5 in. (64 mm). Figure 15c shows the design of an accessible crossing surface at the Opryland theme park in Nashville, Tennessee, which includes an insert in the flangeway of sufficient length to accommodate wheelchairs and motorized carts. The passage area is clearly marked for safe use. More than one-third of the respondents to this synthesis questionnaire reported that ADA requirements are not considered in the construction and maintenance of grade crossings. The MTJTCD and the Railroad-Highway Grade Crossing Handbook say little about the design or signing for bicycle paths or for motorcycles crossing railroad tracks. The Handbook states that surface materials and the flangeway width and depth should be evaluated for safety, noting that the more the crossing deviates from the ideal 90-degree crossing, the greater the potential is for a cycle wheel to be trapped in the flangeway. If the crossing angle is less than 45 degrees, consideration should be given to widening the hikeway to allow sufficient width to cross the tracks at a safer angle. The bicyclist should be warned with suitable markings and signs that the trail is approaching a grade crossing. While motorcyclists use the regular roadway, there are similar concerns for skidding and tire width." TRANSPORTATION RESEARCH BOARD EXECUTIVE COMMITTEE 1998
http://onlinepubs.trb.org/Onlinepubs/nchrp/nchrp_syn_250.pdf
Convicted Onepeople who want to make it look like they got stuck there.
Are you saying the guy in the video was faking?
The following chair - among others is advertised in the AARP magazine
While, I my view, this may be perfectly adequate for indoor and smooth paved outdoor surfaces - it is patently dangerous when facing a railroad crossing. Front wheels are WAY too small in both diameter and width and the rear wheels are a little on the narrow width when considering flange openings at road/side walk crossings.
I don't believe that it is possible to design a total solution that will eliminate the last 1/000th of one percent risk.
I'm sure that my choice of words will not set well with some people, but I believe that "acceptable loss" ...or "acceptable risk" is going to be necessarily a part of the equation, unless you want to build grade separated pedestrian crossings at every location.
Build to best reasonable standard you can attain, supplement that with education, and hope for the best.
EuclidAlso, because the flangeway is so shallow, sloping back of that wall from vertical will not much improve the ability to operate the wheelchair in attempt to climb a caster out of the flangeway.
The issue, as noted, is that bicycles are still going to bust up engaging that irremediable flange face. Aside from flangeway fillers, the only real 'solution' is that mentioned in my old ROTC manual of railway operations: using a locomotive to form the 'flangeway' in asphalt to conform to its own dimensions, and relying on any other equipment with slightly larger flanges to press the material just that little more out. Such an opening is smaller than even power-chair casters can lock into, and even on a hot day I doubt the weight on a power scooter will sink the casters irremediably into the resulting groove. Of course that was in 1974 to 1980...
(As an aside, 'plastic' flangeway fillers were a known and documented thing in those manuals...)
One must also remember that those scooters don't have much ground clearance, unless they are built for rough terrain. In the Lodi incident, I would opine that this wide opening would have been almost as much trouble as the narrower flangeway.
Keeping as narrow a flangeway as possible would be the best option. Some form of trolley flange filler could be used where necessary.
Plus, as a bicyclist I woud absolutely HATE that "spoke buster" profile.
Well, I know that it's not readily apparent from my original sketch because I reduced the size of the image when posting, but please reference the following in conjunction with the amended sketch at the bottom.
The dimension I have circled in red is 1 7/8 inches, so the depth of the flangeway left remaining by my insert is very nearly 1 3/4 inches.
I think there is a problem because the vertical ridge along the railhead (emphasized by the two red arrows) exceeds the 3/4 inch maximum specified in the ADA standards (door thresholds and floor leveling)
So, unless you are creative, I believe the exposed 1 3/4 inch offset that you need for your flange, is not going to be permitted by the ADA.
Convicted One Euclid So overall, an ideal flangeway would be 3-4” wide and 1.5” deep. The depth would be just enough to clear the flange tip. Are you talking about something like this?: (original image is public domain)
Euclid So overall, an ideal flangeway would be 3-4” wide and 1.5” deep. The depth would be just enough to clear the flange tip.
Are you talking about something like this?: (original image is public domain)
It would be similar to that, but this is what I am referring to, using your diagram for reference:
The flangeway floor would be higher, to about half way up the side wall of the rail head. So the flangeway would just deep enough to accommodate the flange. And if there were occasional, slight interference, the rail seal elastomeric material would yield to the flange without any issues. One could say it would be prudent to give the flange tip say ½” of clearance, but the key to the success of this shallow flangeway rail seal is to have the flangeway as shallow as possible.
Regarding the side of the flangeway furthest from the flange, there are several issues involved. The angle that you show looks like about 30 degrees up from horizontal. The closer to horizontal that angle is, the softer the bump would be as vehicles wheels moving from left to right drop down into the flangeway and then are elevated back up to level with the crossing surface.
However, as that angle becomes closer to horizontal, a vehicle tire will drop deeper into the flangeway, and the deeper it drops in, the greater is the return to roadway surface level.
Likewise this effect also applies to the vehicle tire moving right to left. The deeper it drops into the flangeway, the harder will be the bump impact against the side of the rail head. And that bump cannot be eased by the same angle or ramp effect applied to the flangeway on the side opposite the rail.
So the vehicle wheel striking the rail will become more uncomfortable as the flangeway wall opposite of the rail is sloped back from vertical. Also, because the flangeway is so shallow, sloping back of that wall from vertical will not much improve the ability to operate the wheelchair in attempt to climb a caster out of the flangeway.
Also, the shallow flangeway rail seal product has several “tunnels” running lengthwise through it for the purpose of conserving material and making the structure more pliable to flange pressure as ice and snow builds and is packed by the flanges.
And this could be the difference between road and sidewalk panels. I would see no need to close the gap for vehicle traffic areas.
rdamon Would wider flangeways with a slope to grade reduce the entrapment risk?
Would wider flangeways with a slope to grade reduce the entrapment risk?
Adding to Overmod’s comments: The slope on the side of the flangeway furthest from the rail would not make much difference in the entrapment issue, but it might improve the life of the shallow flangeway rail seal device by reducing the impact of vehicle tires striking it after crossing the rail.
But as you flatten that slope, it lets the tire drop deeper into the flangeway, and thus strike harder on the side of the rail head, which is a vertical wall. I would speculate that the sweet spot would be to slope the side of the flangeway furthest from the rail to lean outward about 30 degrees from vertical.
To mitigate the actual entrapment issue, making the flangeway shallower is the most useful change. So overall, an ideal flangeway would be 3-4” wide and 1.5” deep. The depth would be just enough to clear the flange tip. So this would be a major reduction of flangeway depth, which normally can be equal to the full height of the rail. I don’t not think a 4” wide X 1.5” deep flangeway would be able to trap any wheel chair wheels.
tree68The point of the pothole reference is that one would expect the operator of a vehicle to avoid it, not drive into it and expect to blame someone else for his mishap.
Reviewing the video of the incident that spawned these 3 threads, it really does not appear that the scooter operator was particularly distressed by his "predicament".
I'm surprised to not see waving arms to call attention to his peril. And even if I had no legs at all, I believe I would prefer toppling myself out of the chair and dragging myself to safety with my arms, to getting hit by a train.....unless I wanted to get hit by a train.
The guy in the video doesn't even seem to be cooperating with the person trying to save him, which seems rather odd.
I don't believe you will ever be able to design a flangeway impervious to people who want to make it look like they got stuck there.
EuclidWe don’t know what moves the victim in the recent incident made with his wheelchair that caused it to get stuck on the crossing.
Exactly.
EuclidAs casters cross perpendicular to a flangeway, irregularities in road surface can easily turn the casters 90-degrees to be parallel with the flangeway in a split second. If one or both casters then drop into the flangeway, it can be impossible to drive the chair out of that entrapment.
The video appears to show one of the drive wheels stuck in the flangeway. The drive wheels don't swivel. The operator had to have turned his chair in order to align the drive wheel with the flangeway.
The Google images show a fairly modern concrete panel crossing - the flangeway is already likely at near the minimum width.
The point of the pothole reference is that one would expect the operator of a vehicle to avoid it, not drive into it and expect to blame someone else for his mishap.
And plainly stated in the article on the Canadian incident was that the victim stopped, and then reversed direction. I would opine that had he proceeded directly across, it's likely he would not have gotten stuck.
Are flangeways an issue? That would certainly be the case, based on the amount of literature that exists on fixes.
But that does not relieve an individual of a responsibility to take the safe course. And that is my point.
rdamonWould wider flangeways with a slope to grade reduce the entrapment risk?
tree68there is nothing whatsoever preventing anyone from crossing the rails at a 90 degree angle.
We don’t know what moves the victim in the recent incident made with his wheelchair that caused it to get stuck on the crossing. Casters are easily perturbed out of normal alignment during encounters with obstacles on the roadway. This is very likely at a grade crossing during a flangeway encounter because it can be caused by steering, by reversing direction, or just by the slight irregularities on the road surface next to the flangeway.
As casters cross perpendicular to a flangeway, irregularities in road surface can easily turn the casters 90-degrees to be parallel with the flangeway in a split second. If one or both casters then drop into the flangeway, it can be impossible to drive the chair out of that entrapment.
I would say that this is a much less obvious and much more dangerous hazard than the hazard of striking a pothole in the road. And the legal responsibility does not rest by default on the victim of the hazard just because it was possible for the victim to have avoided it. The responsibility also can fall on the person who created the hazard, and how obvious it should have been to them.
Here is an example of a fatality caused by a wheelchair being stuck in a crossing flangeway:
https://www.vicnews.com/news/b-c-rail-crossing-death-highlights-risks-for-people-in-wheelchairs-watchdog/
From the article:
The Transportation Safety Board of Canada (TSB) says the May 2018 fatal railway crossing accident at Broadway Avenue in Chilliwack highlights “the persistent risks faced by persons using assistive devices.”
The TSB’s report released July 23 reiterates the need for improved safety at railway crossings for people using wheelchairs.
Note that the report by the TSB does not blame the victim for causing his death by reversing his wheelchair, even though there was nothing preventing him from not reversing.
BaltACDMy view is there is insufficient room on either side of the crossing protection equipment for the safe operation of the motorized wheel chair.
On the sidewalk - absolutely. That's probably why they put the ramp in on the NE corner, past the crossing protection equipment.
The SW corner doesn't appear to have the same accomodation.
But that is a completely separate issue - there is nothing whatsoever preventing anyone from crossing the rails at a 90 degree angle.
tree68See for yourself: https://www.google.com/maps/place/38%C2%B007'49.4%22N+121%C2%B016'18.6%22W/@38.1304054,-121.2718372,3a,75y,182.6h,77.45t/data=!3m6!1e1!3m4!1s5PnY9oQejxD0fOPeFIVwtw!2e0!7i13312!8i6656!4m5!3m4!1s0x0:0x0!8m2!3d38.13038!4d-121.27183?hl=en
My view is there is insufficient room on either side of the crossing protection equipment for the safe operation of the motorized wheel chair.
BaltACDAnd your problems with ADA requirements. Sidewalk was not passable for the scooter. There was no room on either side of the crossing protection for the scooter to pass. If ADA were complied with, there would be passage for those power scooters.
The crossing equipment on both sides of the crossing is a problem. On the north east side, however, there is a ramp back onto the sidwalk just past the equipment - the scooter user would have to go briefly into the street to reach it.
None of that changes the fact that there is absolutely nothing preventing a scooter, bicycle, or anything else, from crossing the rails at a 90 degree angle on the alignment of the sidewalks.
For that matter, there is a clear 20+ foot approach on three of the four sides. The fourth (NE side) is tighter, but there is still plenty of room to directly cross the tracks, then turn.
See for yourself: https://www.google.com/maps/place/38%C2%B007'49.4%22N+121%C2%B016'18.6%22W/@38.1304054,-121.2718372,3a,75y,182.6h,77.45t/data=!3m6!1e1!3m4!1s5PnY9oQejxD0fOPeFIVwtw!2e0!7i13312!8i6656!4m5!3m4!1s0x0:0x0!8m2!3d38.13038!4d-121.27183?hl=en
charlie hebdo BaltACD Euclid tree68 So, the question is why the operator turned around on the crossing. I don't know what the answer is, but why should we expect a person in a wheel chair to realize he could die from making a U-turn on a sidewalk? I would think that wheel chair users are quite used to the pivot-turn ability and use it impulsively without hesitation. Maybe he was turning around because he forgot something and was going back to get it. What difference does it make? Like railing on stairways, we put guards on things where a hazard may be unrecognized. Ray Charles and Stevie Wonder could see the problems of trying to turn the chair at that point in the side walk/roadway. The guard that should have been in place - 'Sidewalk is Closed' use roadway. A bizarre analogy. Euclid made a reasonable point. What's your problem with handicapped people?
BaltACD Euclid tree68 So, the question is why the operator turned around on the crossing. I don't know what the answer is, but why should we expect a person in a wheel chair to realize he could die from making a U-turn on a sidewalk? I would think that wheel chair users are quite used to the pivot-turn ability and use it impulsively without hesitation. Maybe he was turning around because he forgot something and was going back to get it. What difference does it make? Like railing on stairways, we put guards on things where a hazard may be unrecognized. Ray Charles and Stevie Wonder could see the problems of trying to turn the chair at that point in the side walk/roadway. The guard that should have been in place - 'Sidewalk is Closed' use roadway.
Euclid tree68 So, the question is why the operator turned around on the crossing. I don't know what the answer is, but why should we expect a person in a wheel chair to realize he could die from making a U-turn on a sidewalk? I would think that wheel chair users are quite used to the pivot-turn ability and use it impulsively without hesitation. Maybe he was turning around because he forgot something and was going back to get it. What difference does it make? Like railing on stairways, we put guards on things where a hazard may be unrecognized.
tree68 So, the question is why the operator turned around on the crossing.
I don't know what the answer is, but why should we expect a person in a wheel chair to realize he could die from making a U-turn on a sidewalk? I would think that wheel chair users are quite used to the pivot-turn ability and use it impulsively without hesitation. Maybe he was turning around because he forgot something and was going back to get it. What difference does it make?
Like railing on stairways, we put guards on things where a hazard may be unrecognized.
Ray Charles and Stevie Wonder could see the problems of trying to turn the chair at that point in the side walk/roadway.
The guard that should have been in place - 'Sidewalk is Closed' use roadway.
A bizarre analogy. Euclid made a reasonable point. What's your problem with handicapped people?
And your problems with ADA requirements. Sidewalk was not passable for the scooter. There was no room on either side of the crossing protection for the scooter to pass. If ADA were complied with, there would be passage for those power scooters.
Euclid... but why should we expect a person in a wheel chair to realize he could die from making a U-turn on a sidewalk?
Would you be as charitable if he had run his chair into a pothole and tipped it over, resulting in an injury?
He wasn't on a sidewalk - he was on a railroad crossing. There is a difference.
Knowing his experience level with both the crossing and the chair says a lot. If he had crossed there many times before, with that scooter, one would think he would know to go straight across and not try to turn within the guage.
tree68So, the question is why the operator turned around on the crossing.
Like railing on stairways, we put guards on things where a hazard may be unrecognized
rrnut282 How many incidents have happened at 90-degree crossings where the flange caused the issue?
I surmise that there are other factors that caused this incident.
While the placement of the crossing protection devices is poor at best, scooters such as the victim was using have a virtually zero turn radius. One could be within three feet of the rails and do a 360 degree turn.
If only a caster wheel was caught it would be one thing. But one of the main drive wheels was caught as well. This means the scooter had to have been turned to align with the flangeway.
The video from the officer seems to show the gates starting to come down as the officer arrives. It appears the scooter was already stuck at that point.
So, the question is why the operator turned around on the crossing.
Also unanswered is how familiar the operator was with the crossing, and/or the scooter . Was this an everyday event for him? Or was this his first time on a crossing or with the scooter?
How much wheelchair or bike traffic uses this crossing?
It's possible that some sort of flangeway protection might have prevented the incident, but I'd like to hear answers to the other questions.
Overmod rrnut282 How many incidents have happened at 90-degree crossings where the flange caused the issue? The one that started all these discussions, for instance. The issue of flange gaps (and railhead slickness) is of minimal importance for 'constrained' 90-degree crossing (hence the difficulty about being unable to constrain crossing to that angle with above-the-railhead "guides") but in the particular case you had someone in a power scooter who appears to have tried zero-turn on the crossing, which led to one of his directional casters dropping into the flangeway and becoming wedged there. The same might occur for a bicyclist changing line when passing over a crossing, for example to avoid another vehicle, and having the front wheel abruptly jerked into the line of the flangeway and precipitating a spill if not worse damage. Aall the good intentions and careful signage in the world will not eliminate problems like those.
The one that started all these discussions, for instance. The issue of flange gaps (and railhead slickness) is of minimal importance for 'constrained' 90-degree crossing (hence the difficulty about being unable to constrain crossing to that angle with above-the-railhead "guides") but in the particular case you had someone in a power scooter who appears to have tried zero-turn on the crossing, which led to one of his directional casters dropping into the flangeway and becoming wedged there. The same might occur for a bicyclist changing line when passing over a crossing, for example to avoid another vehicle, and having the front wheel abruptly jerked into the line of the flangeway and precipitating a spill if not worse damage. Aall the good intentions and careful signage in the world will not eliminate problems like those.
The situation was caused by having the crossing protection stanchions in the middle of the side walk area on either side of the crossing. Who or what created that situation thereby prevented the power chair operator from being able to have a 90 degree angle of attack unless he took the power chair out into the roadway.
rrnut282How many incidents have happened at 90-degree crossings where the flange caused the issue?
One wrinkle I haven't seen discussed yet. Flangways only present a real obstacle to wheelchair users and cyclists when crossing at a shallow angle. Most crossings are at 90-degrees between rail and alternative modes of travel. How many incidents have happened at 90-degree crossings where the flange caused the issue?
I can see the benefit to those users at shallow angle crossings, but not so much at the square crossings. If only applied to shallow angle crossings, that greatly reduces the need or utility of flangeway remediations.
daveklepperWhat about slab-track for grade crossings?
I find I do not remember how significant the difference is between, say, slab and concrete ties when the same pads under the rails and clips/anchors are used. It is possible that only minimal stiffness or tuning issues might be observed.
But the crossing would have to be installed top-down, very carefully, and any settlement or cracking would have to be carefully and attentively managed. Of course this would also affect the line and surface of the road, particularly at the edges.
Meanwhile no practical type of main-line slab track embeds the rails in the slab, so you continue to have the entire cost of decking the crossing; the only real advantage being you can cast the bearing points for the decking a bit more precisely and so maintain alignment a bit more thoroughly. Flangeway issues would therefore be exactly as they are for existing crossings -- concrete, plastic, or elastomer -- as would the type and maintenance of any strips or pieces used to reduce flangeway depth.
1. I posted a buch of newly scanned 71-73-year-old photos of Connecticut Co. on the Classic Trains Forum, and several show T-rail - girder-rail joints.
2. Question for those more knowledgable: What about slab-track for grade crossings?
Euclid, I know you are recommending treatment other than girder-rail for "real railroads." But I did want to affirm that you are correct about streetcar curves.
New Haven Division, Connecticut Company, used girder rail for curves and switches, T-rail elsewhere. And their Manufacturers Railway subsidary did move freight cars through those curves and switches.
daveklepperI do not believe I have had enoough "real railroad" hands-on experience to weigh-in on wether or not any of Euclid's ideas are applicable to the "real railroads"
Dave,
I don’t understand what you mean by this comment. It sounds like you are saying that I have proposed applying girder rail to heavy rail lines, and you don’t know if that would work. To be clear, I have never proposed anything of the sort.
Perhaps others here believe that girder rail would improve crossing flangeway safety on heavy rail systems. But if they do, they have not actually said so, or described how it would be done.
What I have clearly stated is that I believe most of the solution to flangeway safety issues at heavy rail grade crossings would be made safer by the use of a modern, manufactured product that is on the market today. This product would be attached by having several features that would fit to the stock rail features, and then made secure by the use of some form of clips.
This product is apparently called a “rail seal,” but I don’t know if that is a brand name or a generic name. The rail seal basically seals up the flangeway groove at a grade crossing so the flangeway is shallower than the full depth flangeways used on many heavy rail crossings.
These full depth flangeways are about 3-4” wide and extend down to the ties where there are open voids between the sides of the ties, under the rails, and into the voids contained in the crushed rock ballast. Snow can fill many of these voids, then partly melt, releasing water, which then freezes to form ice. This is a problem for the railroad company because it can cause derailments.
The other problem with flangeways is the safety issue of people getting stuck in them and the discomfort of driving over them due to the bump effect of the wide open flangeway. This is not a problem for the railroad company other than perhaps some degree of legal liability. So there are two problems; a safety problem for the public and another safety problem for the railroad industry.
The railroad industry sees the solution to their problem as having the largest flangeways possible. The reasoning seems to be that if you have a small space that catches and traps debris, then make the small space bigger. If the railroads had their way, they would make the flangeway so large that there is no longer any crossing.
The public crossing users see the solution to their problem as having the smallest possible flangeways. So they have developed a version of the rail seal that is actually a flangeway filler. It actually eliminates the flangeway for any passage of pedestrians, bicyclists, or wheelchair users. But when a train shows up, its flanges compress the flangeway filler to make way for the flanges.
Generally I read that the railroad industry does not want to use these flangeway fillers that require the flanges to compress the rubbery material used for the fillers. Apparently, the industry regards any move to reduce their full flangeway size as being objectionable, and the smaller it becomes, the more they object. They seem to draw the line at the point of completely filling the flangeways with the resilient rubbery material.
But there is a compromise position that I think is ideal and both sides would be well served. For the public, the flangeways will be as shallow as practical, and so wide that it solves most of the pedestrian-related dangers. For the railroad industry, the wide, and shallow flangeway combined with a debris exclusion feature of the rail seal will practically eliminate any problem with ice or debris accumulation. This compromise solution is called the “Shallow Flangeway Rail Seal.”
This device has a flangeway that is always open enough to clear the flange, but the size of the flangeway is only about 4” wide and about 1.5” deep. This flangeways groove is too shallow and wide to get bicycle or wheelchair wheels, or pedestrians’ feet stuck in it. The only hazards it does not eliminate are the chance of pedestrians stepping on the rail, and bicycles being diverted by their wheels following the flangeway and being guided by it.
The only issue the heavy rail industry would have with this solution is that it makes their preferred largest possible flangeway smaller. So they see that as worsening the problem of collecting packed debris and production of ice fouling.
However, it is claimed that the new Shallow Flangeway Rail Seal prevents debris packing and ice buildup just by the design shape that seals the underlying deep well flangeway that normally collects debris when left open. And its flexible, non-stick material aids the passing wheel flanges ability to clean out the ice with each pass.
So this Shallow Flangeway Rail Seal solves the railroad’s problem that they believe to be caused by flangeways being too small, and yet it does this by making flangeways smaller. At the same time, it eliminates most of the flangeway danger to the public.
I do not believe I have had enoough "real railroad" hands-on experience to weigh-in on wether or not any of Euclid's ideas are applicable to the "real railroads" Overmd and NP Eddie and others are far more qualified. I can point out that as far as I remember, South Shore still uses regular T-rail in the concrete-paved Michigan City street. But refreshing memory with a photo, I see North Shore did use (some?) girder-rail in MilwaukeeL
I believe New York City was one f the cities that required new track in pavement to be girder rail for streetcar companies.
The needs and practice of streetcar companies are different than main-line railroads. The loads carried by wheels are far lower and speeds generally lower. And curves are generally far sharper. Treads are typically narrower, with exceptions, and flanges shallower. On a main-line railroad, the flanges are helped by the wheell taper and the fillet jointing the flange to the tread. with their often doing more of the guiding than the flanges. because of the outer rails see a larger diameter wheel, effectively, than the inner wheel. All this doesn't apply to streetcar operation, where the flanges do the job.
If ware is equal nn the gauge face face of the outer raili and the guard face of the inner (Girder) rail, then maximum life of the rail installatim for the cdurve is insured, and both rails will need replacement at the same time. And guage integeraty will be maintained. This also means ware on both sides of wheel flanges.
Euclid I understand what you are saying about the flangeway protection function of girder rail. I do find references that seem to say that is the only function of girder rail. However, I also find references to the function being as I describe to prevent derailing on ultra-sharp curves found on tramways. If you read the links and quotes I posted on the previous page, they go into intense technical detail about this function of using girder rail to double the flange contact from 2 points to 4 points per wheelset. They also say that this function has been widely misunderstood by the users of girder rail.
I understand what you are saying about the flangeway protection function of girder rail. I do find references that seem to say that is the only function of girder rail. However, I also find references to the function being as I describe to prevent derailing on ultra-sharp curves found on tramways. If you read the links and quotes I posted on the previous page, they go into intense technical detail about this function of using girder rail to double the flange contact from 2 points to 4 points per wheelset. They also say that this function has been widely misunderstood by the users of girder rail.
I took a quick look through the links, and noted that the emphasis was on U.K. practice with American practice being a bit different. In US practice, there was a modification of the grooved rail design where the lip on the gauge side of the groove was raised higher than the head, where standard groove rail the top of the lip was approximately level with the head. There were guard rails that were designed to bolt on to the web of T rails.
OM:
The groove rail sections that I've seen show the bearing portion of the railhead directly above the web, with the outside edge of the groove on the gauge side of the web.
I hope by now everyone has read the references that Euclid cited, including the part where their author specifically points out why proper 'tram' groove rail has little place on conventional track. Much of what Euclid is saying is best understood with specific reference to the precise section involved, of which this is a representative example:
http://www.tautonline.com/wp-content/uploads/2015/08/Wheelrail-part-2.jpg
The immediate thing to note here is the assumption of partial flange bearing for even slight deflection from centerline (note the portion that is 'eased' for sharp curves). This is specifically referenced at a couple of points in the author's discussion, including his note on "diamond" crossing design in part 2. This appears to involve precisely the sort of thing leading to the proscription on flange bearing in United States practice where higher than tramway speed is expected.
I also noted the author's mention of PCC truck design at the end of part 2, specifically in a discussion of low running noise. It seems to me that at least some of his thinking is that the flexible wheels inherently damp the noise of double-faced contact, whereas Mr. Klepper treats the screech as almost a matter of course on curves sharp enough to warrant full flange bearing (against the angled gauge face) and back bearing.
I would conclude that fairly frequent re-turning of wheels to accurate profile would be needed to preclude severe noise, with diameter being comparatively little concern down to the tread wear limit, the condition being that the whole of the wheel, including the flange diameter and profile and the back 'gauge face' all being machined each time -- not just the 'normal' tread and fillet areas.
Erik_MagSince crossings compose a very small portion of track, it would probably be most efficient to bolt the sections to form the flangeway. That way the main portion of the rail would be of the same section as adjoining rails.
[/quote]OTOH, there may be an advantage to having a special section with a much greater vertical stiffness for crossings.[/quote]This was anathema for many years, and even after the Amtrak-sponsored research into bridge tuning, I still consider it so. A typical crossing, whether 'paved' or sectional, has a dramatic effect on resonance of the track. You often see this in wear patterns in the railhead a few feet back, or in signs of repeated rail repairs or welds in the approach. Making this worse with an abrupt change in modulus that INCREASES the effective stiffness seems counterproductive to me. Having a better approximation to a tuned transition, for example welding multiple short lengths of different section in the shop with the running and gauge faces aligned, then normalizing and finish-grinding, would be a better idea (it would be to known length and easily field-welded with proper tieplating to match) but this would be a relative lot of work for what is supposed to be small actual gain ... at least up to any current PSR-economical track speed.
Euclid It would seem cheaper to just use T-rail and add a second timber or iron to define the flangeway. The crossing provides plenty of solid structure to which the extra flangeway feature could be nailed or bolted to. On the other hand, the girder rail does provide a ready-made flangeway that may save time in installation. And for street railway systems with extensive trackage embedded in the street paving, I can see why they might like to embed the U-shape trough with the pavement finished accurately right up to the trough. I would not be surprised of some street railways used girder rail for flangeway definition alone, and had no need for using it on curves. So the entire user/company institution in such cases may never have been aware of the function of girder rail as providing better guidance though curves.
It would seem cheaper to just use T-rail and add a second timber or iron to define the flangeway. The crossing provides plenty of solid structure to which the extra flangeway feature could be nailed or bolted to.
On the other hand, the girder rail does provide a ready-made flangeway that may save time in installation. And for street railway systems with extensive trackage embedded in the street paving, I can see why they might like to embed the U-shape trough with the pavement finished accurately right up to the trough. I would not be surprised of some street railways used girder rail for flangeway definition alone, and had no need for using it on curves. So the entire user/company institution in such cases may never have been aware of the function of girder rail as providing better guidance though curves.
Hilton and Due's book on interurbans has several paragraphs on the choice of rail for tracks in the street. The interurbans very much wanted to stay with standard T rail (or girder T rail) as opposed to girder grooved rail. The use of girder grooved rail was mostly dictated by the terms of the franchise granted for permission to use city streets. The book does mention the problem of debris in the groove.
Many of the sources I've alluded to date back a century or more, revealing the thinking at "the time of the trolley". This was also the time that street railways were starting to use rail that was close to steam RR T sections as opposed to inverted "U" channels and other shapes. As for "girder" rail, the broadest definition is a tall (e.g 8" to 9") section as opposed to 5" to 7" height for standard T rail. The increased height of the rail increased the vertical stiffness to help keep the rails in vertical alignment with the pavement.
Since crossings compose a very small portion of track, it would probably be most efficient to bolt the sections to form the flangeway. That way the main portion of the rail would be of the same section as adjoining rails. OTOH, ther may be an advantage to having a special section with a much greater vertical stiffness for crossings.
Erik_MagThe writings I've come across on grooved rail indicate that the primary purpose was to accommodate vehicles by providing a flangeway precisely defined by steel as opposed to pavement - paving stones or bricks can chip or shift, concrete can chip and asphalt can plastically deform. Little is said about the groove acting as a guard rail.
So taken all together, I assume that there are two completely different and unrelated functions claimed for girder rail. I do not know if this was the original intent. I completely understand the logic of the derailment protection function. But I don’t quite understand the logic of the flangeway protection option.
If the U-shaped appendage of girder rail only has the function to act as curbing to keep pavement away from the flangeway, it seems like there would be far more cost effective way to provide that advantage than to integrate that heavy curbing into the rolled stock rail. Also, while the rail flangeway has the ability to resist encroachment of paving, dirt, rock, etc., it also has the ability to harbor those materials if they do happen to get kicked into the U-shaped trough. And then these contaminants are entrapped precisely in a perfect manner to damage wheels, flanges, and the rail if impacted by the flanges running in that U-shaped trough. So is the trough feature actually protecting the flangeway or turning it into a hazardous entrapment for debris?
Also, while the trough acts as curbing to define the smallest flangeway possible, to protect pedestrians and horse hooves, all of the accumulating broken pavement and debris from the crossing structure is still right there in the crossing as a hazard to pedestrians, bicyclists, horses, and people in wheelchairs.
Overmod. Euclid is right, and the monthly magazine of the UK-based Light Railway Transport Association devoted considerable space to this subject in issues abut a year ago. But you are correct about noise, and even here in Jerusalem I hear the screetch when the flange oilers are not working properly or just have not been refilled. If you think back to the days when your riding streetcars was common, you may recall that screetch. It was more noticeable witih rubber-in -suspension PCC cars and Third Avenjue's 626-645, which had much less general clatter and banging than those conventional streetcars having nothing interrupting metal-to-metal between car-body and motors and gears and rails. So the screech was the primary noise on curves without proper flangeway lubrication.
Again, the New Haven Division of Connecticut Company used girder rail only on curves, and West Penn used a metal strip with tabs for spiking to the ties.
Welding dissimilar rail types on street railways was normal practice, and large sysems had one or even several full-time track-welding crews, and inspections and repair were routine.
tree68Consider that fact that the girder rail being discussed would have to be somehow spliced into the rest of the rail. Any mechanical joint represents a point of failure. Welding the girder rail into conventional CWR will likely raise issues of its own.
Were this approach to be used, the 'girder rail' would be reserved only to crossings, and perhaps only to the portion of a crossing reserved as 'handicapped/differently-abled' access- no more than a few feet. On either side the extension would be cut and ground smoothly back to rail profile. No more than a couple of feet of normal profile would be needed for field welds, either flash butt or thermite. As crossings are sometimes jig-built and brought for installation as panels, fabrication of sections of winged rail of any shop configuration could easily be made under controlled conditions, especially at the small scale needed for pedestrian-only (no bicycle accommodation)
It would seem to me that a separately applied solution would be cheaper, and easier, never mind the other issues being raised.
Let's consider the actual number of crossings compared to total mileage.
If we use an average crossing width of 100', and use my county as an example (mostly rural, a few "urban/village" crossings), there are approximately 25 crossings in fifty miles, for just 2,500' of track. That 50 miles is CWR, like the rest of the line.
There are areas where 25 crossings would cover several hundred miles.
Consider that fact that the girder rail being discussed would have to be somehow spliced into the rest of the rail. Any mechanical joint represents a point of failure. Welding the girder rail into conventional CWR will likely raise issues of it's own.
Heavy rail systems using girder rail to make flangeways safer for the public is the last thing in the world that heavy rail management would do. It runs completely contrary to their preference for large flangeways. They worry about ice and debris in their flangeways, and also don’t trust the flexible, normally flush flangeways to open for their flanges in cold weather. So what are they going to think of a heavy, rolled steel flangeway that is no larger than that contour of their flange cross section?
blue streak 1But is a flangeway rolled onto 132 rail will perform at a much lower pound rating.
There is kinda-sorta the ability to do explosive welding of a 'girder-style' flangeway onto the side of head-hardened rail ... but how it would be cost-effective, I can't say. I thought about doing this for just the walkway section of rail through a crossing (laser keyhole welding with preheat is an option for fabrication before placement) but I think the future, if there is one, for flangeway 'safing' still will belong to separate elastomer filler strips
Bear in mind that grovved rail was almost entirely made for street railway use, where axle loads were often below 10 tons and rarely much above 10 tons.
Having "said" that, the extra steel used for the groove does provide some vertical stiffness, though doesn't provide much material for wear.
But is a flangeway rolled onto 132 rail will perform at a much lower pound rating. Anyone know the individual weight of a standard flangeway ? Need to add the weight of the flangeway to stock rail to get the desired operating rail weight. that is a 40 pound flangeway would need a 172 pound rail stock to get 132 pound rated rail for loaded trains ?
Just for grins, I re-read the grade crossing section in W.M. Camp's Notes on Track, 2nd ed. (C) 1904. Quite a bit of discussion on flangeways, with horses' hooves as the main concern. Some configurations had the danger of ripping off a good chunk of the hood by catching on the shoe. The descriptions of placements for planks in the crossing were for right angle crossings only.
The writing implied that grooved rail was a fairly recent thing in 1904.
The writings I've come across on grooved rail indicate that the primary purpose was to accommodate vehicles by providing a flangeway precisely defined by steel as opposed to pavement - paving stones or bricks can chip or shift, concrete can chip and asphalt can plastically deform. Little is said about the groove acting as a guard rail.
But you are fighting against old thinking on the railroads.
We are discussing girder rail because it was brought up as a suggestion that the purpose of girder rail was intended to be the minimization of the flangeway size. It seems clear to me that the purpose is to reduce the propensity for derailments on the extremely sharp curves of tramways. Girder rail does have an integrated grove that can at least sometimes virtually match the contour of the flange cross section. And if that girder rail were embedded in a grade crossing surface, it would indeed look like the smallest flangeway possible.
So one might assume that girder rail often used on trams mostly operating in streets would have very small flangeways to minimize the discomfort felt by people in vehicles, so frequently crossing the tracks with vehicles, because the tracks are in the streets and share the streets with vehicles.
Interestingly, the current thinking in heavy rail circles is that the smallest, least intrusive flangeways are exactly what they don’t want even if they are more comfortable and less dangerous to pedestrians. What heavy rail seems to want is the largest possible flangeways. This is because they see flangeways as constrictions that entrap snow, ice, and other debris which can become a derailment hazard as it is packed in by the passing trains. The larger the flangeway is, the more it can hold, which reduces the frequency of needed cleanings, and also limits the ability for trains to compact and lodge the debris.
While this view may be historically true, I think is it wrong to conclude that the new generation of flangeway fillers, rail seals, and shallow flangeway rail seals would contribute to the historic problem of causing derailments due to makeing the flangeway smaller. Those new products might actually end the problem of flangeways becoming blocked by snow and debris, as opposed to outdated thinking that adding the new devices just introduces one more form of flangeway blockage.
And if the new devices do end the flangeway blockage problem by making the flangeways self-cleaning, they will also end most of the danger to bicyclists, people in wheelchairs, and other pedestrians.
It is not, but we can discuss the idea of rolling a flangeway onto, say, 132lb rail to look at the implications. We don't have to get into the fabrication, hardening, grinding and resonance issues with such rail, or the reasons FRA bans nonflexible shallow flangeways entirely, until after he has worked the more basic stuff out.
Pardon the interruption, but streetcar girder rail is not the same thing as flangeway fillers or guards at road crossings on heavy freight lines.
EuclidBut with girder rail, you have two guidance means per wheel, working in opposite directions. So this doubles the rail holding grip provided by the two flanges of the wheelset.
What I thought was precisely what you noted earlier: if the outer wheel starts climbing the rail then the inner flange backside starts to make contact, just as on a bridge guardrail, and precludes derailment. Normal running (centered on cone without flange contact) and all the normal fillet transition to full flange bearing would not cause even transient contact of inner flanges.
blue streak 1 Is it possible tht heavy rail does not want girder rail because there are always a few RR cars that the guage of an axel is not corrrect and that would cause a problem ? c
Is it possible tht heavy rail does not want girder rail because there are always a few RR cars that the guage of an axel is not corrrect and that would cause a problem ? c
Girder rail is for making rail climbing events less likely on the most extremely sharp curves, which are found on tramways as they follow street layouts. For the most part, heavy rail systems have to need for girder rail because they have gentle curves.
In a rail climbing derailment, the wheel naturally climbs the outer rail of the curve. With a loss of flange contact as the outer wheel climbs up and over the side of the rail head, the opposite wheel on the rail of the inner side of the curve is free to be simply be pulled off of its rail as the outer wheel climbs over its rail. The flange of the inner rail is not in a position to prevent the wheel being pulled off the rail as the outer wheel flange climbs over its rail. So when a wheel flange tends to climb its rail, the flange on the opposite wheel cannot prevent it.
However, girder rail provides an additional flange guiding surface for each wheel. So when a flange tends to climb the outer rail of on a curve, the inner wheel is prevented from being pulled off its rail by the backside of its flange being retained by the extra rail surface provided by the “U”-shaped groove in the girder rail.
So with normal rail, a wheelset has two flanges with their outer faces being active in guidance. That is one guidance means per wheel and it only works in one direction of lateral shift of the wheelset. But with girder rail, you have two guidance means per wheel, working in opposite directions. So this doubles the rail holding grip provided by the two flanges of the wheelset.
That and it would be a different part to stock and not able to be thermite welded.
.
I do not recall ever reading of an incident due to an out-of-gauge wheel-set.
Brooklyn, The Bronx, Queens. and Manhattan streetcar tracks in pavement were nearly all girder rail. One unusual exception was on Surf Avenue, Coney Island, tracks not replaced from horsecar days, "L-rail," the flangeway without the guard-rail. T-rail was used on unpaved track with normal guard rails on curves.
A possibly more important reason is that railheads are slowly worn down, which means at some point the groove will no longer be deep enough to clear the flanges. While it is possible to make the groove deeper by grinding, the process would be a royal pain in the posterior. The other possibility is to have a deeper groove initially, but that tends to defeat the purpose of using grooved girder rail.
I'm guessing that wheelsets that are out of gauge sufficiently to cause problems with grooved rail will also cause problems with frogs on switches and crossings.
Considering that the context of street railways is like one boundless grade crossing, it might be expected that they would be designed with the smallest flangeways to provide the least inconvenience to vehicles and pedestrians. And, girder rails do provide the smallest flangeway possible.
The heavy rail industry, however, seems to prefer the largest flangeway possible in order to provide the least possible chance of fouling the flangeway. So this position places them in conflict with the public desire for the least flangeway disruption to pedestrians and vehicles. Thus, large versus small seems to be the flangeway dilemma.
So, while the girder rail can serve the purpose of flangeway size reduction, I would be surprised to learn that it has ever been installed in heavy rail grade crossings for that purpose. Heavy rail systems are in perpetual conflict with the public interest on the matter of flangeway size, and only regulatory pressure can reduce flangeway size on heavy rail systems.
I have never seen an actual girder rail that I recall. I have only seen references to them in railroad equipment catalogs, and was slightly curious about their purpose. So, with the subject mentioned here, I have sought to find the purpose of girder rails, and find that it is to increase the guidance in the extra sharp curves of tram systems. I have not found any reference to the purpose being to minimize flangeway size to reduce interference with road crossing traffic. But there may indeed be such references.
Here is 2-part reference to the function of girder rails that gets into a lot of detail about how they use the backside of the wheel flange to achieve guidance in addition to that provided by the rail side of the flange:
Understanding the wheel/rail interface – part one
http://www.tautonline.com/understanding-the-wheelrail-interface-part-one/
Understanding the wheel/rail interface – part two
http://www.tautonline.com/understanding-the-wheelrail-interface-part-two/
Most of the information I refer to is in Part Two. This includes a highly detailed cross section drawing of the interface between flanged wheel and girder rail.
Both Eric and Euclid are correct. There was at least one streetcar system, and Connecticut Company's New Haven Division, that used girder rail only on curves. Somehow, flangeways were kept clear of enroaching pavement. It's not a prolem with concrete pavement or with traditional paving stones.
West Penn did not use any girder rail. even on curves in street trackage. They either used traditional railroad-type guard rails or a plain steel band with flanges bolted or spiked to the ties under the pavement. Their one-time trolley-freight connection, Pittsburgh Railways used lots of girder rail, and PAT light rail may still have some on the over-the-mountain emergency connection for use when the Mt. Washington Tunnel is closed. And possibly some where RoW is shared with buses.
Jerusalem iLight Rail is almost 100% (German) girder rail, even on the limited un-paved RoW. All tracks on on private RoW, except that most is paved for emergency vihicles.
The only tracks not girder rail are in the yard and shops.
The purpose of grooved girder rail was to provide protection for the flangeway as well as making the flangeway as small as possible. The metal on the gauge side of the groove was to prevent pavement away from the gauge side of the rail head.
A fair amount of girder rail was rolled specifically to handle streetcar wheels with smaller flanges than normal RR wheels to minimize trapping of wagon and early truck wheels (think steel tired wood wheels). Normal RR wheels would be riding on the flanges and not the treads.
There may be grade crossing flangeways made by bolting a channel or maybe a “Z” shape length of steel to the rail web. However, the girder rail in a grade crossing would look like an intended flangeway, even though it continues as the stock rail and is not just confined to the crossing as a flangeway would be.
However, if perceived as a flangeway in a crossing, the girder rail flange groove would indeed suggest the tiniest of flangeways intended to offer the least discomfort and danger to vehicular and pedestrian traffic. So it would easy to perceive that as being its purpose.
My understanding is that the girder rail is intended to provide more protection against derailment for trams rounding exceptionally sharp curves. Rather than just the one outer wheel (to the curve) being protected against rail climbing by the field side of its flange; the inner wheel adds protection against rail climbing by the back side of its flange bearing against the corresponding field side of the groove in the girder rail. So each flange uses both of its sides to guide the wheels.
Overmod Bolted? What you're describing sounds like 'girder rail', which I always thought was rolled in one piece to that profile, not fabricated, and which was a mainstay of street running where 'permanence' was important.
Bolted? What you're describing sounds like 'girder rail', which I always thought was rolled in one piece to that profile, not fabricated, and which was a mainstay of street running where 'permanence' was important.
I've seen a drawing for a bolt on guard rail, but I agree it is much more likely to be a rolled section. I've seen that section called both "grooved rail" and "grooved girder rail" - both were definitely rolled to that profile and not fabricated. Richey's "Electric Railway Handbook" uses "girder rail" to describe profiles taller than standard profiles for a given weight, and were available in "tee", "tram" or "grooved" profiles. Doane's "Electric Railway Engineering" uses "girder" rail to refer to the "tram" proflie, with a flat surface, the tram, projecting from the gauge side of the rail head to form a flat bottomed flangeway.
One concern with grooved rail was dirt or other stuff accumulating in the groove and causing a derailment.
blue streak 1I have observed on streetcar and light rail lines what appears to be a metal U shaped flangeway bolted to the gauge side of rails.
Bolted? What you're describing sounds like 'girder rail', which I always thought was rolled in one piece to that profile, not fabricated, and which was a mainstay of street running where 'permanence' was important. As you note this was 'paved in' and thereafter kept swept out -- I sort of ASSumed that traction flangers had 'fingers' that would run in girder rail to clean out anything that wouldn't 'broom'.
Personally the problem I have with such a thing on main lines is that, if you have a rock wedged in such a particular hard place, the thing that's going to give on impact is the metal in the wheel. And that is something that is never good, whether it is only a piece of the flange or a larger chunk of tread or split across the web.
This poster is confused. I have observed on street car and light rail lines what appears to be a metal U shaped flangeway bolted to the guage side of rails . On the inside of the 2 rails the pavement is completely filled with concrete or asphalt. Would that be more expensive but more permanent ?
Some form of the shallow flangeway type must be what the UP is using at five or more crossings in my town. The mainline is three tracks and many heavy freight trains plus Metra daily. It's one of the busiest spots in the US for freight. No derailments.
SD70Dude Euclid SD70Dude We have enough problems with derailments caused by obstructed flangeways. Good luck convincing the railroads and regulators to deliberately put stuff in them. According to the product claims, the purpose and benefit of the flangeway fillers is two-fold: To eliminate the flangeway hazard to the public using the crossing. To eliminate the flangeway ice and debris obstruction hazard to trains. How much real-world testing have they done? How many crossings are they installed on? How much cleaning and maintenance do they require?
Euclid SD70Dude We have enough problems with derailments caused by obstructed flangeways. Good luck convincing the railroads and regulators to deliberately put stuff in them. According to the product claims, the purpose and benefit of the flangeway fillers is two-fold: To eliminate the flangeway hazard to the public using the crossing. To eliminate the flangeway ice and debris obstruction hazard to trains.
SD70Dude We have enough problems with derailments caused by obstructed flangeways. Good luck convincing the railroads and regulators to deliberately put stuff in them.
According to the product claims, the purpose and benefit of the flangeway fillers is two-fold:
To eliminate the flangeway hazard to the public using the crossing.
To eliminate the flangeway ice and debris obstruction hazard to trains.
How much real-world testing have they done?
How many crossings are they installed on?
How much cleaning and maintenance do they require?
I don't know those answers to those questions, but am looking into finding them. Generally what I find and conclude is that the concept did not exist before about 2008, and at that time, I find one case of research and development grants being offered, along with a set of guidelines.
At this time, I conclude that full height flangeway fillers are being used on LRT lines, but none are used for heavy rail lines. However, there is also a new development of flangeway fillers that are not full height, but rather, set at the elevation half way from the bottom of the rail ball to its top. This appears to be under development and referred to as a ”Shallow Flangeway Rail Seal."
This design approach does not require much, if any, flexing of the seal body to accommodate the passage of interfering flanges. Also, the entire body of the rail seal is installed to act as a gasket to keep snow, dirt, other debris, and most water out of the crossing pocket that encompasses the embedded rail.
With much current practice, there are deep and wide open gaps not only on the flange side but in many cases also on the field side. Rail seals completely fill the field side gap and fill the flange side gap to the extent of leaving a relatively smaller flangeway, but not as small as the shallow flangeway version of a rail seal I mentioned above.
For the “shallow flangeway” version, the flange gap is about 2.5" wide by 1.5" deep. I expect this to be developed for use with heavy rail applications that include freight trains. It has a flangeway that is not so small that it requires the flangeway floor to compress as flanges pass over it; but still wide enough and shallow enough to eliminate much of the foot, or wheel entrapment hazard. It is the “sweet spot” size configuration.
The full flangeway fillers are really not necessary for wheel chairs. But the sweet spot flangeways are still able to pose a hazard to bicycles, although it is a greatly reduced hazard compared to the jumbo wide and full rail depth flangeways currently in use on many freight railroads.
So the very best are the full flangeway filler, but I think that is a bridge too far. With them, the rail seal elastomer material does totally interfere with the passing flanges, so the material must compress about 1.5” under each passing flange and then rebound to normal height after the train passes. And this does have to happen at high train speed, so the severe compression and release may even build up significant heat in the material.
As this design has been tried in the recent past with freight railroads, I suspect the rail seals may have been molded with a solid cross section. And also there were likely some poor choices of elastomer material used. Solid section material chilled to sub-zero temperatures may very well have rendered the flangeway fillers to be incompressible by the flanges. Then the flange weight on the solid material might have caused it to fracture and spall out, thus causing short life and frequent replacement as has been mentioned to some extent in various references. Yet the concept has been adopted for LRT railroads and must therefore work okay for them.
The most important claim for the industry is not only does the Shallow Flangeway Rail Seal not constitute a flangeway obstruction that adds to the snow, ice, and debris that needs to be cleaned out of flangeways, but it also renders the normal flangeways able to remain free of those blockages by making the crossing flangeways self-cleaning.
With the latest versions of these devices, the ideal elastomer material is probably used, and instead of being molded solid, they are extruded with hollow cores. You can see that in several patent illustrations. So if these shallow flangeways do happen to collect snow and ice, the flanges will much more easily compress the elastomer by collapsing its hollow cores, as opposed to the extra force it would take to compress solid elastomer material that was likely tried in the past.
Ice that freezes to adhere to these more flexible floor shallow flangeways will not bond as well as it does when sticking to concrete, wood, and steel of the conventional jumbo flangeways. And an ice buildup in the flexible flangeways will interfere with the passing flanges, thus tending to cause the flanges to lift. But the flexible flangeway material, the poor ice bond to that material, and the extreme weight on the flanges will result in the flanges easily cracking the ice and shattering it, and expelling it from either side of the flangeway.
charlie hebdoThere must be some reason why fillers are so resisted on here, even though many are around and in use on major US railroads even in norhtern Illinois which has plenty of snow and ice. No derailments at crossings with fillers here. Perhaps out-of-date thinking?
Perhaps the difference between Main Line trains at track speeds of up to 79 MPH, or in some cases more and secondary lines and industrial spurs being operated on at Restricted Speed.
There must be some reason why fillers are so resisted on here, even though many are around and in use on major US railroads even in norhtern Illinois which has plenty of snow and ice. No derailments at crossings with fillers here. Perhaps out-of-date thinking?
Thanks to Chris / CopCarSS for my avatar.
Yes, but is it known to the State of California to cause cancer?
BaltACDMakers of products claim many things that their products don't deliver.
Hey - it sounds good on paper!
Makers of products claim many things that their products don't deliver.
SD70DudeWe have enough problems with derailments caused by obstructed flangeways. Good luck convincing the railroads and regulators to deliberately put stuff in them.
There are numerous flangeway filler designs out there from different companies all over the world. The hazards are just an excuse to spend nothing and do nothing. Here are just a few.
https://www.nap.edu/read/22800/chapter/5
http://www.freepatentsonline.com/y2020/0063374.html
https://www.environmental-expert.com/products/flangeway-filler-strip-126618
Overmod tree68 Two threads on this aren't enough? Previous experience with Euclid and his predecessor Bucky have taught you that little?
tree68 Two threads on this aren't enough?
Previous experience with Euclid and his predecessor Bucky have taught you that little?
I'm still waiting for 'Terex' to join the chat......
We have enough problems with derailments caused by obstructed flangeways. Good luck convincing the railroads and regulators to deliberately put stuff in them.
What I meant is that extraordinary care, discipline, and 'situational awareness' are necessary wherever flanging is necessary to clear packed snow and ice out of 'flange clearance' areas, likely complicated because of the need in unimproved crossing flangeways - almost a what-is-not-forbidden-is-mandatory thing. And this likely being the case for a particular line until ALL its crossings have been fully 'top-fillered'...
Either very precise location or very careful vigilance is needed as even one 'miss' involves potentially huge consequences. Not so much in absolute safety, but in rapid-response costs to 'remediate' what gets torn up or torn out if there is one little slip...
OvermodThis is a cute treatise but it fails to address the #1 issue with flangeway fillers since the Lord proposed them to Noah: what about flanger operation?
Maybe I misunderstand your point, but to my knowledge, flangers have no ability to run through a grade crossing and clean out the flangeways. Flangers are intended to cut snow below the cut bottom of a snow plow pass which is maybe 3-6” above the top of the rail. Then a flanger is run to cut more snow out to a lower elevation to about 3-5” below the tops of the rails. The flanger blade is notched out at each rail location so it can cut below the top of the rail elevation along the outside of the rails and in between them.
While snow plows can pass right over a grade crossing just like on the rest of the track, flangers must be raised in order to pass over a grade crossing. Otherwise, it will snag the crossing planks and tear them out or it will derail the flanger and probably the locomotive pushing it.
This is why there is a flanger sign posted on both sides of every grade crossing. It is to tell the flanger operator to raise the blade to clear the height of the crossing. Flangers must also be raised for other features such as switches, railroad crossings (diamonds), guard rails and tie spacing timbers on bridges and trestles, and anything else that is built up higher than the tops of the ties.
But to the point of flangeway fillers or railseals interfering with ice removal, I have read the manufacturer’s claims that flangeway fillers and railseals actually eliminate the ice accumulation problem with grade crossing flangeways. I detail this in the last paragraph of the first post here.
So, I conclude that both railseals with their very shallow flangeway and flangeway fillers with no flangeway at all actually solve the icing problem that is the reason for the extremely wide and deep flangeways in the first place.
So instead of viewing this as the flangeway filler or railseal merely offering a smaller or practically non-existent version of the current giant flangeway; it is actually that the filler or seal make the smaller flangeway possible by their ability to exclude ice and snow buildup without resorting to a giant flangeway to give more capacity to hold ice and snow.
tree68Two threads on this aren't enough?
He has done very good critical thinking about the risks to power chairs; that alone makes this thread distinctively relevant as a thread...
This is a cute treatise but it fails to address the #1 issue with flangeway fillers since the Lord proposed them to Noah: what about flanger operation?
About the best I have come up with in a great deal of time is very precise GPS beaconing that can raise and lower flanger cutters at these crossings, for example via a high-accuracy version of that grade-crossing location app that has now disappeared; or some kind of ramp analogous to those used for some kind of steam-locomotive water scoop that trip retract when encountered ... I don't agree with automatic re-extension but professionals may laugh at me for that.
I also toyed with the idea of a relatively large-diameter sectional wheel, in place of a straight flanger cutter, that would break up and expel ice from the gap, but just press down full-height elastomer fillers -- didn't some sleet cutters work a comparable way? In constant running these would dress the gauge face of the rail continuously and by extension even 'pickable' facing points without throwing them open...
Two threads on this aren't enough?
If two threads are good, three must be better...
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