地震波振幅对黄土-泥岩边坡动力响应规律的影响

研究地震作用下黄土-泥岩边坡动力响应特征，对边坡的稳定性评价和抗震设计具有重要指导意义。基于边坡的离心机振动台试验和数值模拟分析，研究地震波振幅对边坡地震动响应的影响规律，结果表明：由坡体深部至浅表层，黄土-泥岩边坡的水平向和垂向加速度放大效应呈非线性增加，且水平向大于垂直向，在坡体顶部到达最大，表现为趋表效应和高程效应；在边坡内部岩性接触部位，黄土层内动力响应较大，泥岩中动力响应较小，表现为岩性效应；随着输入地震波振幅的增加，坡体动力响应表现为先增大后减小的趋势，当输入振幅达0.3g时，坡体动力响应最大。黄土-泥岩边坡的变形破坏过程为：随输入地震波振幅增加，坡顶逐渐形成拉张裂缝，不断扩展，坡体中上部溜土，产生向临空面方向的位移，坡体中部发生鼓胀隆起，局部坡体振动松散，岩土体滑落至坡脚堆积。

Influence of seismic wave amplitude on dynamic response of loess-mudstone slope

Studying the seismic dynamic responses of loess-mudstone slope is important for the slope stability evaluation and engineering aseismatic design. The effects of seismic wave amplitude on the seismic dynamic responses of loess-mudstone slope are investigated by the centrifuge shaking table tests and numerical simulation. Results show that: the amplification of horizontal and vertical acceleration of loess mudstone slope increases nonlinearly from deep to shallow surface of the slope. The horizontal amplification is greater than the vertical, and it reaches the maximum value at the crest. The dynamic response of the loess layer is larger than that of the mudstone inside the slope. With the increasing of the amplitude of the input seismic wave, the dynamic response of the slope increases first and then decreases. When the input amplitude reaches 0.3g, the dynamic response of the slope reaches the maximum value. The deformation and failure process of the loess-mudstone slope could be summarized as: with the input of seismic wave amplitude increasing, tension crack formed at the crest, gradually expands, displacements develop towards the free face, and then overlying loess raises lightly, some soil accumulats at the slope toe.