Work posponed actually not completed due to weather. Now is Dec 20 - 21. New announcement hhas exact location of work.
http://www.dart.org/riding/cbdrailreplacement.asp
Overmod Buslist In this TCRP document its interesting that in section 1.2.5 it specifically notes that the Feds exercise no regulatory control over transit agencies, it's purely a state issue. Sorry to be an idiot, but I can't find the TCRP document. Can you put the link to it up again, or provide a download URL or reference?
Buslist In this TCRP document its interesting that in section 1.2.5 it specifically notes that the Feds exercise no regulatory control over transit agencies, it's purely a state issue.
Sorry to be an idiot, but I can't find the TCRP document. Can you put the link to it up again, or provide a download URL or reference?
click on your "does it look like this?" link, that is the TCRP document. It won't let me back in as I've viewed it "too many times!"
Falcon48 Overmod Falcon48 They were using some sort of jigs on the surface above the rails and the pavement, the purpose of which wasn't entirely clear. I'm pretty familiar with track construction techniques on regular railroads, but I had never seen anthing like this. My guess was that they were jacking up the track structure from above to level it, since they were also injecting some kind of material (possibly a slurry) into the track structure. This sounds like top-down alignment to me. Does anything here look like what you saw? Edit: Here is a video of some of the rail-replacement activity: This is exactly what I saw. Note that, in this picture, the rail seems to be still in place.
Overmod Falcon48 They were using some sort of jigs on the surface above the rails and the pavement, the purpose of which wasn't entirely clear. I'm pretty familiar with track construction techniques on regular railroads, but I had never seen anthing like this. My guess was that they were jacking up the track structure from above to level it, since they were also injecting some kind of material (possibly a slurry) into the track structure. This sounds like top-down alignment to me. Does anything here look like what you saw? Edit: Here is a video of some of the rail-replacement activity:
Falcon48 They were using some sort of jigs on the surface above the rails and the pavement, the purpose of which wasn't entirely clear. I'm pretty familiar with track construction techniques on regular railroads, but I had never seen anthing like this. My guess was that they were jacking up the track structure from above to level it, since they were also injecting some kind of material (possibly a slurry) into the track structure.
This sounds like top-down alignment to me. Does anything here look like what you saw?
Edit: Here is a video of some of the rail-replacement activity:
This is exactly what I saw. Note that, in this picture, the rail seems to be still in place.
Fantastic! Whatever I was going to do tomorrow is on hold. I am off to Dallas to see some of the action in person.
blue streak 1 So far there has not been any answer as to what kind of maintenance this is. Is it preventative maintenance ( PM ) or is it mainternance need to correct a major defect ?. Cannot remember any of the other light rail / streetcatr installations that have been added in the last 30 years having a major defect repair. Granted that there have been a few emergency repairs due to collaspe of track grade. The repair of rail ( might not be what the actual repairs are ) does seem to be premature ? One thought maybe the subgrade is unstable ? The picture slightly reminds me of grout repairs to highways ?
So far there has not been any answer as to what kind of maintenance this is. Is it preventative maintenance ( PM ) or is it mainternance need to correct a major defect ?. Cannot remember any of the other light rail / streetcatr installations that have been added in the last 30 years having a major defect repair. Granted that there have been a few emergency repairs due to collaspe of track grade. The repair of rail ( might not be what the actual repairs are ) does seem to be premature ?
One thought maybe the subgrade is unstable ? The picture slightly reminds me of grout repairs to highways ?
Actually if you watched the video above or on the DART website it was pretty clear they were replacing the rail. Further you can google the DART map and see the lines converge approx at Unioin Station and diverge at approx St. Paul station and you can presume that with DART vehicles transiting this portion of shared trackage (among all DART light rail lines) every 3-5 min it probably gets significantly more wear then the rest of the system. I think that would be a very safe presumption. Below is a further explanation which was in the Google results.....
http://forum.dallasmetropolis.com/showthread.php/103255-DART-Downtown-Transit-Mall
DART's weekend ridership is usually dramatically lower than during the week. This is why the replacement of the rail in the transit way is being done on the weekends.
The one exception is on those weekends when special events are underway, i.e. The State Fair of Texas, an American Airlines Center event, etc.
Buslist blue streak 1 DART rail ( Dallas ) has announced that all light rail routes in downtown Dallas Thanksgiving ( Nov 27 ) to (?) Sunday for rail replacement of worn rail. Bus bridges will be connecting outer portions of light rail systems 8. Any other possibilities ? With all the light rail routes in Dallas why have alternate routes not been installed in downtown to allow maintenance or other detours ? . Why are there no alternative routes? It's simple $! Would you rather use available money for an occasionally used detour route or for a further extension into unserved territory. Admittedly the closure is inconvenient but it's rare and on a holiday weekend. Hard to justify the occasionaly used alternative route if you leave taxpayers unserved daily. If you don't like this approach you'd hate living in the UK where the holidays have maintenance closure after closure And things take 2 to 3 times as long there as they do here. Having said that, DART is starting to plan on a second route across downtown and according to a recent report in a subway. And remember the extent of the closure does not necessarily reflect the extent of the work, but convenient points to turn trains back and provide bus connections.
blue streak 1 DART rail ( Dallas ) has announced that all light rail routes in downtown Dallas Thanksgiving ( Nov 27 ) to (?) Sunday for rail replacement of worn rail. Bus bridges will be connecting outer portions of light rail systems 8. Any other possibilities ? With all the light rail routes in Dallas why have alternate routes not been installed in downtown to allow maintenance or other detours ?
DART rail ( Dallas ) has announced that all light rail routes in downtown Dallas Thanksgiving ( Nov 27 ) to (?) Sunday for rail replacement of worn rail. Bus bridges will be connecting outer portions of light rail systems
8. Any other possibilities ?
With all the light rail routes in Dallas why have alternate routes not been installed in downtown to allow maintenance or other detours ?
.
Why are there no alternative routes? It's simple $! Would you rather use available money for an occasionally used detour route or for a further extension into unserved territory. Admittedly the closure is inconvenient but it's rare and on a holiday weekend. Hard to justify the occasionaly used alternative route if you leave taxpayers unserved daily.
If you don't like this approach you'd hate living in the UK where the holidays have maintenance closure after closure And things take 2 to 3 times as long there as they do here.
Having said that, DART is starting to plan on a second route across downtown and according to a recent report in a subway.
And remember the extent of the closure does not necessarily reflect the extent of the work, but convenient points to turn trains back and provide bus connections.
BuslistIn this TCRP document its interesting that in section 1.2.5 it specifically notes that the Feds exercise no regulatory control over transit agencies, it's purely a state issue.
In this TCRP document its interesting that in section 1.2.5 it specifically notes that the Feds exercise no regulatory control over transit agencies, it's purely a state issue. So over in the thread on the delays to the Atlanta streetcar operation citing Federal testing requirements, it obvious the wrong guys are getting blamed.
Falcon48They were using some sort of jigs on the surface above the rails and the pavement, the purpose of which wasn't entirely clear. I'm pretty familiar with track construction techniques on regular railroads, but I had never seen anthing like this. My guess was that they were jacking up the track structure from above to level it, since they were also injecting some kind of material (possibly a slurry) into the track structure.
blue streak 1 Was wondering about corrugation as well. Does DART or any light rail system have its rail passed over by a rail grinding operation ? What about heavy rail subways ?
Was wondering about corrugation as well. Does DART or any light rail system have its rail passed over by a rail grinding operation ? What about heavy rail subways ?
Frankly, it was difficult to determine exactly what they were doing. If they were replacing the rail (which wasn't that clear, at least when I looked at it), they were doing it in a way that didn't require tearing up the pavement, or removing the rail structure underneath the rails. They were using some sort of jigs on the surface above the rails and the pavement, the purpose of which wasn't entirely clear. I'm pretty familiar with track construction techniques on regular railroads, but I had never seen anthing like this. My guess was that they were jacking up the track structure from above to level it, since they were also injecting some kind of material (possibly a slurry) into the track structure. They also had a fabric on top of the track structure on Sunday morning which they removed later in the day. Again, the purpose of this was not clear. Maybe someone who's more familiar with this project than I am can explain what they're doing.
With respect to corrugation, it's easy to tell if there's excessive corrugation on a rapid transit system because the corrugation will cause an ear splitting roar when a train passes over it (if you ride BART in the Bay Area and you'll see - or, rather, hear - what I mean). I haven't noticed anything like this on DART. Whatever condition they are fixing, I doubt that it's corrugation.
The NYC Subway has a rail grinder.
I am sure they are only replacing rail in specific places, not the whole system. That would take much longer. It might be a few curves that have worn, or perhaps replacing turnouts. Or maybe there are some sections where rail corrugation was allowed to become too severe. A complete closure makes carrying out such projects much more efficient, causing less long-term intermittent disruption and higher cost.
More than likely the electrical folks will take advantage of the closure to work on the power distribution system.
They installed the rail in the mid-1990's. All the DART light rail lines use the one downtown route that is being replaced on 3.5 to 5 minute headways. No idea what the rail is in the city downtown as it is below the pavement but it looks to be over 100 lb rail in the suburbs (looks like Heavy Rail to me).
This appears a little confusing.
1. How long has this rail been installed. ?
2. Approximately how many rail cars over this rail ?f
3. What weight rail is this ?
4. Manufacuter ?
5. Has anyone heard of light rail wearing out this quickly ?
6. How much being replaced ?
7. Installation error ?
Here is DART announcement
If you plan to travel on Dallas Area Rapid Transit or the Trinity Railway Express during the long Thanksgiving holiday weekend, check the following before starting your trip:
Find answers to your route and schedule questions at www.DART.org.
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