为分析研究地震作用下斜坡的稳定性,采用Phase2有限元软件,建立考虑最不利荷载对斜坡稳定性影响的数值模型,分析地震水平峰值加速度0.1 g条件下不同监测位置模拟的位移和地震加载时间关系曲线以及斜坡位移场、应力场和剪应变增量的变化情况。研究表明受水平地震加速度的影响,坡面法向应力减小,下滑力增加,沿着滑动面向下移动;斜坡中部位移极值达到0.36 mm,地震加载时间4 s时处于失稳状态。随着地震加载时间的增加,斜坡发生累计破坏效应,强震作用下斜坡最易于发生瞬时溃滑。
In order to research the stability of slope under seismic loading, finite element software Phase2 was employed to establish a numerical model of slope stability under most unfavorable load. The model was used to analyze the relationship between displacement and seismic loading-time at different monitoring positions under 0.1g peak value of horizontal acceleration as well as the variation of slope’s stress field, displacement field and shear strain increment. Result showed that influenced by horizontal seismic acceleration, the normal stress of slope decreased, and the sliding force increased and moved down along the sliding surface. The extreme displacement in the middle part of the slope reached 0.36mm, and slope failure occured when the seismic loading time reached 4s. With the increase of seismic loading time, the slope suffers accumulative damage. Instantaneous collapse and slide is most likely to happen under strong earthquakes.
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