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I am working up the bridge rail transition for the MGS Guardrail System. In previous discussions, I recall that you said we could use a transition that was already approved by FHWA, however we would need to incorporate the "transition to the transition".

As you may recall, John Rohde worked with us to obtain approval from FHWA for adapting the Alaska Thrie Beam Transition to connect with WYDOT's TL-3 and TL-4 twin steel tube bridge rails. I have attached a mirror image of the Alaska design along with details for option "K" of the simplified transition recently tested by MwRSF.

I have a few questions to help me understand how to proceed:

1. Do we substitute only the last 12'-6" of the Alaska Design into the last 12'-6" of the MwRSF tested option?
2. For the MwRSF tested transition, the next section upstream of the double nested 12'-6" segment is a 6'-3" single thrie beam section. The post spacing drops to a quarter post spacing (18 ¾") as it approaches the double nested 12'-3" section, so do we need to add one additional post into the Alaska design between posts A6 and A7 so there is a consistency in the progressive stiffness of the system?
3. In the car crash test, I noted significant snagging of the vehicle as it impacted in the area of the asymmetric w-beam to thrie beam section, although the test was a pass. Would it be prudent to add one additional half post spacing between posts M11 and M12? This would essentially be option "L" I believe. Although the Pooled Fund voted to test option "K" since it would require one less post, I remember you guys were much more confident of option "L" passing.
4. What do we need to do to gain FHWA approval for this transition?
5. Please let me know your thoughts concerning any other issues you feel relevant to this discussion.