View Q&A

Weak-Post W-Beam Guardrail Attached to Culvert

State IN
Description Text Within the Weak-Post W-Beam Guardrail Attached to Culvert report TRP-03-277-14 Figure 80 shows the rail lap on the second weak post from the end of the culvert and
a 12 ft section of rail from that lap location. We have assumed that this detail just shows what was constructed for the test and as long as we follow the placement
recommendations within section 6. Summary, Conclusions, and Recommendations, the location of the rail laps and length of rail used within this system do not have to
follow Figure 80. Are we correct? Thanks
  • Guardrail
Other Keywords Headwall-Mounted Weak Post, Lap Location
Date November 7, 2019
Response That is correct. The detail in the report shows standard 12.5' rail segments. However, longer rail sections would be acceptable. The location of the first splice in the weak post rail could also vary without affecting performance. 

We do recommend maintaining the 75" post spacing between the last standard MGS post and the first weak post on the bridge rail.

Date November 8, 2019
Response Thank you for the response, you mentioned longer rail sections would be acceptable.  Would shorter rail segments be acceptable to help meet site specific locations.  We have attached a PDF with a possible scenario.
Date November 18, 2019
Attachment Weak Post Shorter Panel Length Question.pdf