STABILITY RESEARCH OF TANGJIASHAN LANDSLIDE IN WENCHUAN EARTHQUAKE
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摘要: 根据唐家山边坡滑坡前的基本地形地貌,建立相关模型,采用Mohr-Coulomb准则,利用折减强度法计算其安全系数,并分析在地震波作用下唐家山滑坡的稳定性状况。安全系数计算结果显示,边坡模型在自然状态(即只有重力作用)下的安全系数为1.46,表明边坡在自然状态下是相对稳定的。选取汶川地震最初30秒幅值较大的地震波,对边坡采用自由场边界条件进行分析计算,结果表明边坡在地震作用下将在坡面产生贯通的塑性区,这一塑性区与真实的滑坡坡体一致,由于地震加速度的作用边坡将产生较大的位移和速度,这些大的位移和速度在边坡滑坡后将产生巨大的能量,造成灾难和损失。Abstract: The numerical model of Tangjiashan landslide is established to analyze its slope stability with Mohr-Coulomb theory and the strength reduction method. Firstly, the slope stability is simulated numerically under the natural state (only with the gravity action), and the calculated safety factor is 1.46, which indicates that the slope is relatively stable under the natural state. Secondly, Tangjiashan landslide stability is numerically simulated with large amplitude seismic wave of initial 30 seconds in Wenchuan earthquake, and calculates the free field boundary condition for the slope. The results show that the piercing plastic zone in slope is produced in Wenchuan earthquake, and the simulation plastic zone is good agreement with the real landslide slope body. Because of the earthquake acceleration, larger displacement and velocity of the slope appearing, which produce tremendous energy in the landslide and cause serious disaster and loss.
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Key words:
- Wenchuan earthquake /
- Tangjiashan landslide /
- slope stability /
- safety factor
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表 1 边坡材料参数
Table 1. Rock mass parameters
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