Logged in as: Public User

Thrie beam/Barrier plate attachment

State WI
Description Text

We have some structures people retrofitting thrie beam to sloped end treatments.  Prior to reading the report on retrofitting thrie beam transitions, I was instructing them to put the a connecting plate (see drawing) to get the rail vertical closer to vertical.  I did this based on some crash tests done at TTI.


Based on the retrofit research, should they be installing the plates?


Is having the plate above the sloped transition an issue (see email and associated attachment below)?


Given that our sloped end section and the blunt end section can allow interaction with a vehicle's wheel, should we place something  near the bottom of the barrier to prevent this interaction?

  • Approach Guardrail Transitions
Other Keywords none
Date June 19, 2012
Attachment Barrier Detail.pdf


Using the attachment plates to keep the thrie beam vertical is important " we recommend you continue to use them on you installations.  That being said, The attachment plate was not designed for use on sloped end barriers.  Your concerns for snag on that upper corner are justified as previous testing on transitions has shown even small amounts of snag can negatively affect a systems crashworthiness.  My 1st thought to mitigate potential snag issues is to cut the anchor plate to match the slope of the concrete barrier (the 4 5/8" x 7 ½" section detailed in your drawing).


I am still looking for the TTI test report of transition hit with the end shoe on the outside of the guardrail " resulting in snag and vehicle rollover.


Date June 19, 2012

Contact Us:
130 Whittier Research Center
2200 Vine Street
Lincoln, NE 68583-0853
(402) 472-0965
Email: mwrsf@unl.edu
The information contained on the Midwest Roadside Safety Facility (MwRSF) website is subject to change without prior notice. The University of Nebraska and the MwRSF is not responsible or liable, directly or indirectly, for any damage or loss caused or alleged to be caused by or in connection with the use or misuse of or reliance upon any such content, goods, or services available on this site.