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Dynamic earth pressure on Non-yielding retaining wall

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geolover

Geotechnical
Aug 4, 2010
8

there is 16 meter Full-buried parking in a CL-ML soil and there are no groundwater. for this project "soil nailing" is selected for walls as temporary stabilization during parking structure construction.after soil nailing, main structure which has concrete wall will be constructed, I consider K0 for design of parking wall in static condition, because there are limited displacement in wall and it is Non-Yielding (We have 5 floor slab each 3 meter in height)

My question is related to earthquake case . when we use Wood (1973) relation ∆PE=KH. γ. H2 as a over pressure on the wall as dynamic load ,please clarify it must be added to which static load? (case 1 or case 2)

case 1: At rest soil pressure Pst=K0. γ. H2
case 2: Active soil pressure Pst=Ka. γ. H2

introducing reference for this subject, would be highly appreciated.
 
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Note that Pst (I am assuming this is static total wall shear) for both at-rest and active needs a "0.5" in the equation.
There has been a lot of discussion on the seismic pressures on retaining walls by Sitar (UCBerkeley) and Stewart (UCLA) and many others. Like most geo-structural subjects, true behavior is very complex, so gross simplification is necessary for day-to-day design work.
One reference document for seismic pressures on yielding and non-yielding walls in the US is NEHRP 2009 Recommended Seismic Provisions, Part 3, Special Topics in Seismic Design. Free download.
This document also presents both Simplified Wood, and also Ostadan's method. Ostadan is not intuitive or quick.
Adding full deltaPE=(kh(gamma)(H^2) to the full at-rest pressure is conservative for restrained walls.
 
Dear ATSE
Thanks for reference, as you correctly mentioned 0.5 is missed in my post.
 
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