Abstract Dynamic response characteristics and failure process of antidip layered rock slope under strong earthquake are studied by large-scale shaking table model test inputting sine wave in X-direction and XZ-direction. Testing results show that:(1) Acceleration amplification coefficients increase nonlinearly with the increase of slope height. The slope has the nonlinear height effect,i.e. more obvious of amplification more closing to slope top,and nonlinear surface effect,i.e. more intensity of amplification more closing to surface. (2) 3/4 of slope height is the critical height. Horizontal acceleration is amplified more obviously than vertical acceleration while above the height;but when below the height,the vertical acceleration is amplified more obviously. (3) The effect of frequency of seismic wave on the acceleration amplification coefficients is the largest. While the seismic frequency approaches to slope body?s natural frequency,the amplification effect is more obvious and the critical height is lower. (4) The amplitude of acceleration has no influence on distribution of its amplification coefficients in slope;but the larger the amplitude of acceleration is,the more the amplification coefficient is. (5) Failure process of the antidip layered rock slope under earthquake is divided into the following stages:earthquake induction;opening of structural surface at the top of slope;opening of structural surface at slope surface;increases of opening number of surface structural surfaces and depth of opening range,model blocks shearing broken at inner slope;rock structure loose at upper part and slope surface and arc transfixion crack along slope appearing. The zonal deformation phenomenon in the test has testified that distribution of acceleration coefficient in slope body is nonlinear.
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Received: 22 March 2012
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