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Weak-Post W-Beam Guardrail Attached to Culvert
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
Headwall-Mounted Weak Post, Lap Location
November 7, 2019
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.
November 8, 2019
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.
November 18, 2019
Weak Post Shorter Panel Length Question.pdf