Western Railroad Discussion > Dry Canyon Viaduct Update

July 27th, heat straightening continued on the ground for span 9.  Sixteen of the bridge's 19 spans have been reinstalled and all spans have been redecked.  Today installation of the timber ballast deck on span 7 and half of span 8 was completed.  Over the next 24 hours span 9 will be lifted and set and heat straightening will commence on span 11.  Installation of track panels will begin on the north end of the bridge, spans 19 through 12.

It sounds like it will just be a matter of time till Dry Canyon Trestle rises again from the ashes.

Robert Morris
Dunsmuir, CA
Robert Morris Photography

Thanks for the update!

Unless something is really tough to solve, they should beat their reopening estimate by weeks.

It'll be one month tomorrow (July 28) that the Lava Fire knocked out the bridge.  At the current rate of progress we could see the bridge reopen by early next week if not before the end of July.  An amazing effort by all hands!

That's encouraging news in the midst of a lot of bad news. Thank you!

James Nelson
Thornton, CO
www.flickr.com/mojaveflyer

Great news, especially since the BNSF Gateway sub will be out due to trestle damage as well.

Once the MBAs get out of the way, Railroaders and Engineers can do amazing things.  
Headquarters may second-guess some expenses later on  but for now they can't do any harm to the people doing this job.
Thanks for the update.

Very good news. How has UPS been shipping trucks to Portland....I-5 ??

Adam

Heat straightening??  Doesn't that weaken the metal??  Or are the girder spans very over-engineered to allow such heat??

I had to look up heat straightening.  I found this:   https://www.fhwa.dot.gov/bridge/steel/heat_guide.pdf   which looks like a pretty good primer on the topic.

Kit Courter
Menefee, CA
LunarLight Photography

coach Wrote:
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> Heat straightening??  Doesn't that weaken the
> metal??  Or are the girder spans very
> over-engineered to allow such heat??

Read about it way too much for posting on here. Is done on beams for buildings for one that have a bend in them takes real tallent to do it.  

Kit,

Thanks for the link.  I have heard of it, but never saw any documentation on it.  That helps a lot.

CV the civil E in NJ

That's amazing, these RR bridge guys constantly impress me.
Hope someone can post more pics soon.

I realize the need for speed here, but by reinstalling a timber deck aren't they just asking for it to burn again?  

Maybe the chance of a major forest fire in the same area is slim to none for the next 10-20 (or more) years?

 

Agree, thank you for sharing. I was wondering the same regarding heating the metal and not annealing it or hot working the metal and inducing residual stresses, brittle heat affect zones, etc. Apparently this process uses local heating and cooling below critical temperatures for the steel, and most of the correction of the plastic deformation is achieved through the heating and thermal expansion/contraction versus applied external force. I'd be interested in seeing this in action at the job site. I'd also be interested in knowing if they have a mobile lab for doing hardness testing, grain analysis, ultrasonic testing, etc.

Sean

cjvrr Wrote:
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> Kit,
>
> Thanks for the link.  I have heard of it, but
> never saw any documentation on it.  That helps a
> lot.
>
> CV the civil E in NJ

I'm only an MBA so what do I know but I would guess that a ballasted deck would add too much weight.  And for some reason where the bridge ties are laid directly on the girders the railroads seem to use wood not concrete bridge ties.  Perhaps the concrete is to "ridgid".  Perhaps somebody who is smarter than I am can explain all that with more technical insight, and correct me if I am off target.  Perhaps time was also a factor in the choice of repair design.  But sure sounds like the B&B guys are heros.....and probably will have an encore opportunity in the FRC.

JBWX

jbwest Wrote:
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> I'm only an MBA so what do I know but I would
> guess that a ballasted deck would add too much
> weight.

It was and I suspect still will be a ballast deck. The question is why are they using timbers to create the tub. I assume concrete tubs are too heavy for this specific bridge.

The original poster says it will again be a timber ballast deck, as that's what they are installing.

Jim

Shows you how much an MBA knows.  My pix of the bridge led me to believe there was no ballast "trough", but presumably I was wrong. But the question remains, as others have raised, why use wood again.  I'm sure the engineers have a good reason, just curious why.  I'm also wondering why in my limited experience unballasted decks seem to have wood ties even when the track at either end has concrete ties.  

JBWX 

Photo of deck about a week before the fire.

Rich Tower

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