地震作用下边坡潜在破坏面预测研究

STUDY ON THE PREDICTION METHOD OF THE POTENTIAL FAILURE SURFACE OF SLOPE UNDER EARTHQUAKE

实际边坡在地震作用下的潜在破坏面往往并不是预先可以确定的。本文利用时程分析法对地震作用下的均质土坡和顺层岩质边坡进行动力响应分析,以地震波正向峰值时刻和震后瞬间所对应的塑性云图作为研究依据,利用极限平衡法对理想弹塑性边坡的安全系数Fs×(1+5%)范围及其对应的潜在圆弧破坏面范围和塑性区之间的关系进行研究。最终发现对于均质土坡而言,地震波正向峰值时刻和震后瞬间安全系数Fs×(1+5%)所对应的潜在圆弧破坏面范围以及所对应的塑性贯通区具有相似的区域;对于顺层岩质边坡,地震波正向峰值时刻和震后瞬间安全系数Fs×(1+5%)所对应的潜在直线破坏面范围集中在岩层交界面附近,而且两个时刻所对应的潜在破坏面范围十分接近。

The potential failure surface of slope cannot be pre-determined on the condition of earth- quake. This paper analyzed the homogeneous soil slope and bedding rock slope by the process analysis, and on the use of limit equilibrium method, the relationship between the zone corresponding to the safety factor Fs× （ 1 ＋ 5% ） of ideal elasto-plastie slope and the corresponding range of potential failure surfaces was studied at the seismic wave peak moment and the moment after the earthquake based on the contours of plastic strain. Finally, for the soil slope, the range of potential failure surfaces and the zone correspond- ing to the safety factor Fs × （1 ＋ 5 % ）of ideal elasto-plastic slope are very similar; for the bedding rock slope, the range of potential failure surfaces and the zone corresponding to the safety factor Fs × （ 1 ＋ 5% ）of ideal elasto-plastic slope are focused on rock interface, and the range of potential failure surfaces at the seismic wave peak moment and the moment after the earthquake are very close.