Logged in as: Public User

MGS Long-Span post depth

State OH
Description Text We have a location where we are trying to use MGS long-span to its maximum 25' span length.  Even at that length, we are unable to embed the posts adjacent to the culvert (posts 3 and 4) more than 2 - 2.5'.  Do we have any post options (adding concrete, additional posts, ...) that could be substituted for a fully embedded post?

  • Guardrail
Other Keywords none
Date July 12, 2016
Attachment MGS long-span.pdf

Response Currently we do not have reduced CRT post depth options for the MGS long span system. CRT posts are designed to develop forces in the soil that fracture the post at one of two hole locations, one at groundline and a second 15.75" below groundline.

In the long span system, the post functions by supporting the barrier adjacent to the unsupported span  and then releasing to prevent barrier pocketing as the vehicle moves from the unsupported span to the standard MGS. The concern would be that reducing the embedment of the first post adjacent to each end of the span could allow increased deflection of the MGS which may affect barrier performance negatively. 

Thus, we do not recommend using shorter than tested embedment depths for the CRT posts at this time.  
Date July 13, 2016

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.