Distribution of lateral active earth pressure on a rigid retaining wall under various motion modes

The design of retaining walls depends on the magnitude of active pressure exerted from the backfill. Therefore, estimating the scale of this pressure is a fundamental factor in the design. In this study, to assess the active earth pressure, a rigid retaining wall was built capable of translating and/or rotating with adjustable speed. Further, several physical tests were conducted on a laboratory scale under the influence of uniform surcharge. In order to evaluate the behavior of the soil and the failure wedge, circular flat pressure cells and particle image velocimetry method were used. The results indicated that in the translation and translation-rotational modes, the distribution of lateral active pressure along the wall height was non-linear while it was relatively linear under rotation around the base. By increasing the amount of surcharge, the effect of the arching phenomenon at the lower portion of the wall was more evident. This led to a negligible magnitude of pressure at the base of the wall. In addition, it was observed that during the active motion of the wall, the distinction between the stationary region and the failure zone was a function of the mode of wall motion.