关键词: 顺层岩质边坡, 砌块模型, 振动台试验, 地震动参数, 动力响应, 破坏模式

Abstract: Shear failure of bedding slope along weak zone is one of the main types of landslides. The seismic dynamic response and destabilization failure mode of rock slopes with laminated fractured structure were studied by a shaking table model of block masonry slope under the action of multi-dimensional and multi-parameter ground motion, meanwhile, considering the weakening process of mechanical parameters of slope under different working conditions of slopes. The results show that the ground shaking characteristics and geological structure of the slope are the decisive factors to determine the seismic dynamic stability and failure mode of the slope. The horizontal dynamic response of the slope has obvious elevation and slope surface amplification effects, and the elevation has less influence on the vertical dynamic response of the slope. Ground motion amplification effect is related to the mechanical strength of the structural surface, the waveform of seismic waves, and the spectral characteristics, and the sine wave has a more significant influence on the amplification effect of the slope than the natural wave. The slope cracks initiate and expand at the weakest part depending on the dominant structural surface and trace to the joint surface to form creep-slip and locking sections. The strength parameter of the joint surface weakens under the action of the external geological agents so that the potential slip zone appears to be differentiated between the forward failure mode of lap penetration from the rear edge to the front and the backward failure mode from the front to the rear edge, and accordingly the slip mass also evolves from shear exposure at high position to collapse failure.

Key words: bedding rock slope, block model, shaking table test, seismic ground motion parameters, dynamic response, failure mode