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Flangeway Danger to the Public

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Posted by rdamon on Friday, September 11, 2020 11:42 AM

And this could be the difference between road and sidewalk panels. I would see no need to close the gap for vehicle traffic areas.

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Posted by Euclid on Friday, September 11, 2020 11:31 AM

rdamon

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. 

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Posted by Convicted One on Friday, September 11, 2020 11:28 AM

tree68
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.  

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.

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Posted by tree68 on Friday, September 11, 2020 10:59 AM

Euclid
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.

Exactly.  

Euclid
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.

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.

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Posted by Overmod on Friday, September 11, 2020 10:55 AM

rdamon
Would wider flangeways with a slope to grade reduce the entrapment risk?

Marginally.  On the other hand this would make crossing far more bumpy and increase the risk of low-centering.   These may be acceptable 'risks' for pedestrian crossings or the sort of 'bikeway' that includes a couple of sharp right-angle barriers before each intersection "to compel safe lookout"  but would be a disaster for vehicular traffic at any particular speed or load.

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Posted by rdamon on Friday, September 11, 2020 10:16 AM

Would wider flangeways with a slope to grade reduce the entrapment risk?

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Posted by Euclid on Friday, September 11, 2020 9:38 AM

tree68
there 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. 

 

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Posted by tree68 on Friday, September 11, 2020 7:48 AM

BaltACD
My 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.  

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Posted by BaltACD on Thursday, September 10, 2020 11:56 PM

tree68

My view is there is insufficient room on either side of the crossing protection equipment for the safe operation of the motorized wheel chair.

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Posted by tree68 on Thursday, September 10, 2020 11:15 PM

BaltACD
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.

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

 

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Posted by BaltACD on Thursday, September 10, 2020 10:45 PM

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? 

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.

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Posted by tree68 on Thursday, September 10, 2020 10:03 PM

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.

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Posted by charlie hebdo on Thursday, September 10, 2020 9:31 PM

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? 

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Posted by BaltACD on Thursday, September 10, 2020 7:19 PM

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.

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Posted by Euclid on Thursday, September 10, 2020 7:04 PM

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

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Posted by tree68 on Thursday, September 10, 2020 5:48 PM

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.  

 

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Posted by BaltACD on Thursday, September 10, 2020 12:53 PM

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 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.

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Posted by Overmod on Thursday, September 10, 2020 12:47 PM

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.

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Posted by rrnut282 on Thursday, September 10, 2020 12:26 PM

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.  

 

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Posted by Overmod on Thursday, September 10, 2020 11:48 AM

daveklepper
What about slab-track for grade crossings?

The primary issue is probably cost.  But there are operational issues too.

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.

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Posted by daveklepper on Thursday, September 10, 2020 3:29 AM

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?

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Posted by daveklepper on Wednesday, September 9, 2020 12:15 AM

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.

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Posted by Euclid on Tuesday, September 8, 2020 10:11 PM

daveklepper
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"

 

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. 

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Posted by daveklepper on Tuesday, September 8, 2020 6:54 AM

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

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Posted by daveklepper on Tuesday, September 8, 2020 4:31 AM

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.

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Posted by Erik_Mag on Monday, September 7, 2020 11:46 PM

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 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.

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Posted by Overmod on Monday, September 7, 2020 12:38 PM

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_Mag
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.

This is better thinking, but it presumes for some reason that there is an advantage to a fixed-depth flangeway in regular railroad construction -- there is not, either objectively or 'legally'.  The far better practice is that observable in current crossing design: define the 'far' side of the flange gap with an angle or other section cast into the crossing segments, and lay a proper filler into the resulting gap between the lower ball of the rail and the sections once installed and leveled.  Nothing at all is gained by physically attaching anything to the rail, let alone compromising its structure with bolts or material, additive or subtractive.

[/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.

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Posted by Erik_Mag on Monday, September 7, 2020 11:57 AM

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. 

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.

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Posted by Euclid on Monday, September 7, 2020 8:28 AM

Erik_Mag
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.

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. 

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.  

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. 

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Posted by daveklepper on Monday, September 7, 2020 2:03 AM

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.

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