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Highway sign support structures

State NE
Description Text

Can the universal breakaway steel post use the bolts placed in the bottom post/ plate using a keyhole slot?

We have access to the top of the bottom post - for repairs of the top post.

If we slide the bolt against something that keeps the bolt from rotating we can repair it from the top side without digging under it. I'm thinking of something similar to the slot on the flange under my toilet. The keyway does not need to be this long.

For a hex head the bottom would need ribs on each side or a channel from the larger opening back to the left under the small opening to hold the head from turning. (See attached Figure 1.jpg)

  • Mailbox, Sign, Utility, & Luminaire Supports
Other Keywords none
Date April 21, 2011
Attachment Figure 1.jpg


It may be possible to utilize this concept to reduce the clearance on the bottom side of the lower plate to that required to place wrench on bolt head versus to place hand under to hold a nut/wrench. With slots, one would likely need to use thicker plate to account for the weakened region around the hole. However, it may be possible to do this with bogie testing in each direction to compare with final modified design. Bogie testing on final design would also be needed since changes were made between prior crash tests.

Maybe in an upcoming Pooled Fund year and/or if other states are interested in a simplified design, we could investigate this option.

Date May 4, 2011

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