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Two Loop PCB Connection

Question
State NE
Description Text

Has MwRSF tested a 12.5' Concrete Protection Barrier with two loops?

I'm thinking this is from the 2001-2003 era.

 

Have we tested two loops in the end of a concrete bridge rail or median rail?

I thought we tested this with the Kansas style steaked-down with 3 stakes on the traffic side.

Then 2 barriers staked down with 2 stakes each, then 1 or 2 staked down with 1 stake.

What was the name of this research study?

 

Would the tied down barrier move less than the free standing barrier and put less force on the loops?



Portable Barriers



Date June 19, 2010
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The original 350 testing utilized 2 loops per end. Later, we added the third loop to get double shear " top and bottom.

 

The only 2-loop TCB system that was crash tested and evaluated while anchored corresponded to the steel tie-down strap system. And, this TCB used a version where each loop was configured with 3 small bent rebar. All of tied-down systems and transitions used the Kansas version with 3 rebar loops per barrier end.

 

Without detailed analysis, I believe that an anchored TCB would encounter reduced tension within the loops as compared to a free-standing TCB. However, the loops would potentially experience increased shear and moment at the concrete interface if one barrier shifts relative to the other. This shifting has been observed in the anchored barrier testing. Please note that no directed study has been made for comparing the various loop configurations under free-standing and anchored installations.


Date July 20, 2010
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