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TO: K. N. Kirker/Z. Y. Fahoum
FROM: Chuck Ruth
DATE: March 2, 1994
SUBJECT: AASHTO Section 5.5.5,F. S. of Sliding for Retaining Walls


Please prepare a letter for Myint Lwin’s signature to AASHTO requesting clarification on the 1.5 factor of safety. We use a 1.5 factor of safety for DL + LL + EP but reduce this value to 1.1 for DL + DP + EQ. This allows for sliding of the wall during an earthquake to relive seismic force buildup on the wall.

If you have any questions, please contact John VanLund for clarification. I have attached a copy of a memo from John.



cc: J. VanLund