Truss Bridge - HLMR retrofit

[justhumm]

Does anyone have any knowledge of a truss rehabilitation project (anywhere in the world) that involved installing an HLMR bearing at / near one of the panel points to effectively replace the pin?

 

[bridgebuster]

Something doesn't look right with your sketch labels. In a typical cantilever truss, one would expect the cantilever span to be on the left with the suspended span hanging from the vertical. Could you post an elevation view?

 

[EQguys]

justhumm,

Take a look at the first presentation in this video. It is about a project involving pin and hanger replacement at the junction of cantilever-suspended spans. You may get some useful ideas that may be applicable to your rehab project.

http://media.aisc.org/NASCC2016/B06.mp4

 

[justhumm]

@ bridgebuster:

what I posted were just conceptual sketches that someone else created, so I can't (and wouldn't) trust them as bible verse.

...plus this is a really weird bridge.

@ EQguys:

Thanks for the link! Now I have something to do this weekend.

Happy Labor Day, all!

 

[msquared48]

What happens with this joint in a seismic event?

Seems questionable to me without some form of movement limiting venue as it would lead to a loss of vertical bearing and collapse.

Mike McCann, PE, SE (WA)

 

[bridgebuster]

@justhumm - are you free to identify the bridge? In the AISC presentation the one relevant to your situation is the first one up.

@EQguys - thanks for the link; interesting presentations.

 

[justhumm]

@msquared48
At this point, I have no idea what happens to the joint. That's why I am hoping to stumble over a project that actually used this sort of retrofit.

Conceptually, I THINK the "safety pin" that was shown on the sketch is meant to limit the movement.

@bridgebuster
No, I am not at liberty to divulge the bridge identity, right now.

I just watched the first minute or two of the video. I'm going to watch the rest of it later tonight or tomorrow. I was actually able to find the bridge plans for that project on MDOT's website. It's not exactly what I was hoping for, but might make good food for thought...

[URL unfurl="true"]http://sp.mdot.ms.gov/Contract%20Administration/DesignBuild/MDOT%20Project%20No%20BR001501120106487301000%20US%2084%20Pin/Forms/AllItems.aspx[/url]

[URL unfurl="true"]http://sp.mdot.ms.gov/Contract%20Administration/DesignBuild/MDOT%20Project%20No%20BR001501129106736301000%20Westbound/Previous%20Project%20%E2%80%93%20Bridge%20Plans.pdf[/url] (100+ MB file)

 

[bridgebuster]

@justhumm - Thanks for the link to the bridge plans.