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I have reviewed your Approach Guardrail Transition (AGT) details, specifically the details for the 34” tall transition. I have a few comments:

1. The embedment depth for posts 1 – 8, should be increased by 3”.  During testing and evaluation, we raised the height of the guardrail and blockout by 3”, but did not shift the post up.  We did not want to weaken the stiffness of the transition system by reducing the post embedment  depths.  Thus, the blockout and rail were extended 3” above the top of the post, and the embedment depths of 54” for the W6x15 posts and 40” for the W6x9 posts were maintained.  If desired, you could increase the length of the post so that the tops of the blockout and posts match, but it is not necessary as long as you drill/punch new bolt holes 3” above there typical locations.
2.  The 34” tall AGT was tested and evaluated with the standardized buttress.  It appears you have the buttress sketched into your details, but I do not see it called out anywhere. Both the 31” and 34” buttresses are only referred to as “concrete rail.”  .  A note on the buttress design should be added to prevent confusion or incorrect installations.
3. Further on the buttress designs – as of now, your AGT attached to the older concrete buttress has not been evaluated to MASH, only NCHRP Report 350.  The standardized buttress was tested to MASH criteria win combination with a critically weak AGT, thus it was approved your use will all other thrie-beam AGTs.  As such, you should specify the new standardized buttress design for both of the AGT designs.  The only difference between the 31” AGT and the 34” AGT would be the height of the buttress.  For reference, I have attached 2 drawing sets containing the standardized buttress for both AGT heights.