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Retrofit post for approach transitions

State WI
Description Text

A contractor has asked if the welded connection in the attached drawing could be switched to a bolted connection.   There have been locations where the flume is skewed.  This skew flume and needing to line up with the post location needed in the thrie beam transition makes it difficult to use the standard set up.

  • Approach Guardrail Transitions
Other Keywords none
Date May 17, 2017
Attachment 2017-05-17_15-11-40.jpg
Attachment 20170522092121199.pdf

Response It would likely be difficult to provide a bolted option for the plate attachment to the I-section beam as the bolts would likely interfere with the blockout. 

A potentially simpler option would be to increase the length of the plate and slot the holes for the blockout attachment to provide the adjustment needed.

Another alternative would be to slot the holes attaching the cross beam to the support posts to allow the beam to be adjusted.

There is concern that if we slide the surrogate post too close to one of the offset support posts, we will be loading only one side or post of the surrogate post frame and may not get the desired lateral force of a post mounted midway between the supports.

We believe that a + or – 6” toleration on the plate location would be acceptable and still provide for loading of both of the posts on the support structure. 
Date May 18, 2017
Attachment retrofit.jpg


Could they use a button head bolt and provide a recess in the wooden block?


My guess if we got too wild with the location of the plate there could be eccentric loading issue on the beam.

Date May 18, 2017


I think that would work as well. Just thought that the slots would be easier.

Date May 19, 2017

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