Dynamic Centrifuge Study of Seismically Induced Lateral Earth Pressures on Retaining Structures

A set of two dynamic centrifuge experiments on stiff and flexible U-shaped retaining structures with dry medium dense sand backfill was performed in order to evaluate the validity of the various assumptions and analysis procedures currently used for the evaluation of seismically induced forces on retaining structures. The experimental results show that dynamic moments and dynamic earth pressures tend to be overestimated using the current analysis methods. More importantly, the dynamic earth pressure increases monotonically with depth and the maximum measured moments are not necessarily in with maximum measured earth pressure. These results are consistent with results obtained independently for gravity retaining structures and call into question the validity of the basic assumptions in the currently used analysis and design procedures.