• Framingham / Worcester Destressing Project

  • Discussion relating to commuter rail, light rail, and subway operations of the MBTA.
Discussion relating to commuter rail, light rail, and subway operations of the MBTA.

Moderators: sery2831, CRail

  by dbperry
 
Couldn't believe there wasn't a thread on this subject already, but I couldn't find one either...

Earlier today, an observant fellow commuter noticed what sounds like a rail train with lengths of CWR (continuously welded rail) on the siding track on the south side of the Framingham Worcester mainline between CP 22 and CP 23. By the way, what is the name of that siding?

Anyway, perhaps it is the early arrival of the CWR associated with phase 3 of the destressing project:
http://www.mbta.com/about_the_mbta/t_pr ... 6442454462" onclick="window.open(this.href);return false;
Work performed under the first contract, Contract C72CN01, included approximately seven (7) miles of “Rail De-stressing” on the outbound Track #1 between milepost 33 in Westboro and milepost 43 in Worcester. This phase of the project was advertized in the spring of 2014 and awarded to JF White Construction Co. Work commenced in August 2014 and was completed in October 2014.

Work to be performed under the second contract, Contract C72CN02, consists of approximately seventeen (17) miles of “Rail De-stressing” on inbound Track #2 beginning at milepost 4 in Allston and continuing west to milepost 21 in Framingham. Contract C72CN02 was advertised in the fall of 2014 and awarded to JF White Construction Co. in April 2015. “Rail De-stressing” work commenced in early May and is anticipated to be complete in July 2015.

Work to be performed under the third contract, Contract C72CN03, consists of the replacement of approximately fifteen (15) miles of existing sections of 131# (pound) rail with new 136# (pound) rail on outbound Track #1 located between milepost 21 in Framingham and milepost 45 in Worcester. It is expected that this work will immediately follow the completion of Contract C72CN02, commencing in July 2015 with project completion by the end of 2015.
I'll try and get a picture of the rail train at some point. Anyone have any more info?
  by MBTA F40PH-2C 1050
 
The siding that the rail train is putting up on is called the 4th Iron...runs from CP 22 to CP 23. The railtrain has made some good progress this week, only one last section of rail to be dropped as of last night. They have been using the 904E-1072W for power. Today is probably the last day for the photo op btw!
  by F-line to Dudley via Park
 
What is rail "de-stressing"? Is this west-of-Framingham closeout work from the CSX handoff for elimination of the last lengths of CWR subject to summer heat speed restrictions. And/or closeout work for a west-of-Framingham track class uprate opening up some real stretches of 79 MPH?
  by MBTA F40PH-2C 1050
 
F-line to Dudley via Park wrote:What is rail "de-stressing"? Is this west-of-Framingham closeout work from the CSX handoff for elimination of the last lengths of CWR subject to summer heat speed restrictions. And/or closeout work for a west-of-Framingham track class uprate opening up some real stretches of 79 MPH?
The way it was explained to me was that our track dept....or jf white, whomever, where cutting small sections of the rail out, 2-6" and heating it up, and then welding it back together, so that during the summer months of heat, the rail will have that extra room to move around, expand and contract. CSX never kept records of whether or not they did this when the rail was last laid (probably lost in the Conrail take over), so now it is our task to do it. Both to your questions, they are looking for increased speeds on the WML, one step at a time. This line has so much potential in it
  by harshaw
 
This line has so much potential in it
As a Worcester/Framingham commuter this has me excited :)
  by dbperry
 
I read up on this a few years ago when we started to get hit with the continuous 'heat delays' on the Framingham Worcester line.

Here's what I've been able to piece together:

CWR has a Rail Neutral Temperature ("RNT") - the temperature at which there are no thermally induced loads (compression or tension) on the rail. Typically this is the temperature of the rail when it is installed. When it gets hotter than RNT, the rail wants to stretch, and when it gets colder, the rail wants to compress. Stretch too much and it buckles, compress too much and it snaps leaving a gap.

The ideal Rail Neutral Temperature is quite hot - different sources I saw ranged from 81 to 90 to 115. I think there is regional variation for that value. A hot RNT leaves enough 'room' on either side that the rail won't buckle in hot weather or snap in cold weather. Basically the concern is more on the hot side - so having a higher 'starting point' (as in rail neutral temperature) provides more capacity for hotter temperatures to not affect the rail.

For whatever reason, either Conrail or CSX didn't have documentation of the rail neutral temperature or didn't have a high enough rail neutral temperature for the B&A. The project description at the link above hints at this - I never bothered to get the actual bid documents to see if the Framingham Worcester situation is better explained.

So rail stressing or destressing (words which seem to be used somewhat interchangeably, I can't figure out the difference) is the practice of essentially changing the rail neutral temperature. The rail is released from the ties and heated to the desired temperature. This usually requires cutting a small segment from the rail to allow it room to expand. Once it is at the correct temperature, it is reaffixed to the ties and welded to the next section. I think they use some kind of anchor at each weld point to keep each segment in place at the new rail neutral temperature - perhaps forever, or maybe just until the whole section of rail is destressed.

That's what I recall from my reading...this is the only thing I bookmarked. I know I found lots more with google.
https://www.fra.dot.gov/Elib/Document/3036" onclick="window.open(this.href);return false;
  by 130MM
 
dbperry wrote:I read up on this a few years ago when we started to get hit with the continuous 'heat delays' on the Framingham Worcester line.

Here's what I've been able to piece together:

CWR has a Rail Neutral Temperature ("RNT") - the temperature at which there are no thermally induced loads (compression or tension) on the rail. Typically this is the temperature of the rail when it is installed. When it gets hotter than RNT, the rail wants to stretch, and when it gets colder, the rail wants to compress. Stretch too much and it buckles, compress too much and it snaps leaving a gap.

The ideal Rail Neutral Temperature is quite hot - different sources I saw ranged from 81 to 90 to 115. I think there is regional variation for that value. A hot RNT leaves enough 'room' on either side that the rail won't buckle in hot weather or snap in cold weather. Basically the concern is more on the hot side - so having a higher 'starting point' (as in rail neutral temperature) provides more capacity for hotter temperatures to not affect the rail.

For whatever reason, either Conrail or CSX didn't have documentation of the rail neutral temperature or didn't have a high enough rail neutral temperature for the B&A. The project description at the link above hints at this - I never bothered to get the actual bid documents to see if the Framingham Worcester situation is better explained.

So rail stressing or destressing (words which seem to be used somewhat interchangeably, I can't figure out the difference) is the practice of essentially changing the rail neutral temperature. The rail is released from the ties and heated to the desired temperature. This usually requires cutting a small segment from the rail to allow it room to expand. Once it is at the correct temperature, it is reaffixed to the ties and welded to the next section. I think they use some kind of anchor at each weld point to keep each segment in place at the new rail neutral temperature - perhaps forever, or maybe just until the whole section of rail is destressed.

That's what I recall from my reading...this is the only thing I bookmarked. I know I found lots more with google.
https://www.fra.dot.gov/Elib/Document/3036" onclick="window.open(this.href);return false;
Rail De-stressing (and it is "de-stressing" - we certainly don't want to add stress to the rail) is as you say: raising the neutral temperature, or the temperature at which the rail in neither compression or tension. Whenever the rail gets to that temperature again, the rail is stress free or neutral, hence the name. The general theory is that the rail temperature should be higher. This would necessarily increase the odds of a "pull-apart", and reduce the chances of a kink. A pull apart will often, but not always, break the signal bond, and thereby set the signals to Stop and Proceed. While a kink does not disturb the signal system, and leaves the signals at Clear leading up to the kink.

Over my career the target rail neutral temperature(RNT) has gone from 85 to 95 to where it is now at 105. It has been discovered that many maintenace operations will reduce the RNT, and the FRA now requires railroads to have a CWR Plan to describe how these operations are to be conducted to prevent kinks. The general rule of thumb is that if the rail temperature gets to be 40 deg. above the neutral temperature, a kink can occur. In this region rail temperatures can easily exceed 120 deg. So you can see that a RNT of 85 can easily put one in the "kink zone".

And rail anchors are applied over the entire length of a string. They are used with, but are separate from, spikes; and are attached to the base of the rail, and butt up against the side of the tie to prevent lateral movement. Usually every other tie for most of the string. The ends get anchors on every tie. Other means of attachment. like Pandrol clips, act as both spikes and anchors, and there are no separate anchors on the sides of the ties.

Lots of points to be made on the subject.

DAW
  by JWilson
 
Rail anchors are also applied to both sides of every tie for a distance of 200' on each side of various immovable points such as grade crossings, turnouts, non-ballasted bridges, etc. Anchors should be applied wherever they will fit in turnouts. We de-stressed a good sized section of track 2 in Davisville last year but that was on concrete ties so no anchors but with new clips, pads and insulators. Ties, either wood or concrete, equipped with FastClips also do not require anchors since the FastClips provide clamping force similar to the Pandrol e-clips.
  by boatsmate
 
Drove into Boston on Sunday night, Saw the contractor working in the Newton Boston area on Track 1.
  by MBTA F40PH-2C 1050
 
What should be done is what Amtrak has done in times past on the NEC....cancel all weekend service for 2 or 3 weekends in a row, and perform a maintenance blitz on the line, get as much done in 2, 12 hour shifts/per day, in 2 consecutive weekends
  by harshaw
 
MBTA F40PH-2C 1050 wrote:What should be done is what Amtrak has done in times past on the NEC....cancel all weekend service for 2 or 3 weekends in a row, and perform a maintenance blitz on the line, get as much done in 2, 12 hour shifts/per day, in 2 consecutive weekends
exactly. Why this hasn't been done is beyond me. Maybe I should shoot an email over to Charlie Baker? :)

We had an infuriating incident on the Worcester line on Friday. Right before the evening rush hour the MBTA announced speed restrictions. Of course, this was *after* the 2:55pm train but before the 4:05 PM train, removing any chance that passengers could make a judgement call to get home earlier. The best part is that because the T's alerting system sucks you continued to get notices about speed restrictions an hour after they were posted.

Secondly, they cancelled the speed restrictions 80 minutes into the 4:05 pm train. As far as I could tell the temperature didn't really change or maybe even got hotter. I corresponded with @MBTA_CR on twitter (since bizarrely this is the only way you get customer service these days). I complained about about the tardiness of the speed restrictions. Their response:
Heat restrictions are issued when ambient temps (measured in Fram, Worc, Boston) reach 85. We alert as soon as this happens.
When I asked why the speed restrictions were randomly lifted at 5:20 PM they responded:
Heat restrictions are lifted as soon as ambient temperature drops below 85.
So, besides the fact that they are probably using some fisher price thermostat setup, I think the only solution is for the MBTA to post this data as it is measured in real time. Then the rest of us can make a judgement call about if the speed restrictions are likely to happen. For my part, I was in Cambridge where the temperature was 78 degrees, but if I had access to the data I could guess that a speed restriction might be come into effect. I recommended this to @MBTA_CR but of course didn't get a response.
  by dbperry
 
I also got some answers from the twitter folks.

My question was: Since the info page (http://www.mbta.com/about_the_mbta/t_pr ... 6442454462) indicates that phase 1 was completed last year, will heat restrictions still affect the line from milepost 33 to milepost 45 (Worcester)?

Answer from @MBTA_CR: Yes. Heat restrictions will be implemented for entire line until entire project is done. "The destressing aspect is complete in that stretch but other work still ongoing."

I have other questions I'll be asking them...
  by MBTA F40PH-2C 1050
 
dbperry wrote:I also got some answers from the twitter folks.

My question was: Since the info page (http://www.mbta.com/about_the_mbta/t_pr ... 6442454462) indicates that phase 1 was completed last year, will heat restrictions still affect the line from milepost 33 to milepost 45 (Worcester)?

Answer from @MBTA_CR: Yes. Heat restrictions will be implemented for entire line until entire project is done. "The destressing aspect is complete in that stretch but other work still ongoing."

I have other questions I'll be asking them...
good luck getting good answers :P
  by harshaw
 
so Keolis send me this email today (Tuesday). This is for an event 24 hours later. They really aren't good at this stuff.
Do you have questions, concerns or feedback you would like to share?

Join us at our Spring Meet the Managers event for the opportunity to speak with some of the members of the Keolis Management Team!

Managers from various departments will be in attendance to respond to any questions, and provide updates on ongoing or upcoming service initiatives.

Stop by one of the following sessions:

South Station:
Wednesday, June 17th, 4p-6p

Back Bay Station:
Wednesday, June 17th, 4p-6p

North Station:
Thursday, June 18th, 4p-6p
In any case, since this coincides with my commute home, I think I will drop by and ask them my favorite questions about heat restrictions, track work, etc.
  by 130MM
 
dbperry wrote:Answer from @MBTA_CR: Yes. Heat restrictions will be implemented for entire line until entire project is done. "The destressing aspect is complete in that stretch but other work still ongoing."
Well, that isn't correct as we have already lifted the need for any CSX heat restrictions between CP 4 and CP 11 on Track 2.

DAW