Dynamic centrifuge modelling tests for toppling rock slopes

Abstract

Two types of toppling rock slope physical models with intermittent rock planes alone and with both rock planes and secondary rock joints are built of synthetic material, and tested in the centrifuge machine under seismic load. The dynamic response and failure mechanism of the two slope models are then recorded and analyzed. The results of the centrifuge dynamic tests reveal that: the topographic amplification effect is obvious for both two slopes in the same pattern; the secondary rock joints inside the rock slope serve to decrease the dynamic stability of the rock slope significantly; the toppling rock slope without secondary rock joints failed in bending and toppling from the slope foot to the rock layer behind accordingly, but the slope with secondary rock joints failed in a different process, firstly from the upper rock layer due to the penetration of secondary rock joints inside, and then to the underlying rock layers; the dip angle of the final failure plane for the rock slope with secondary rock joints is much higher than the slope without secondary rock joints, and the failure plane was formed in an obvious step-path shape. The failure plane surface standards indicated that the slope with no secondary rock joints failed in shearing at the failure plane, while the slope with secondary rock joints inside broke along secondary rock joints in tension at the failure plane. .