三维加筋折线边坡稳定性上限分析

基于极限分析上限定理,建立了三维加筋土折线边坡的旋转破坏机制,推导了内能耗散和外力功率的解析表达式,同时考虑了加筋强度系数、水平地震力系数以及高度系数、坡角、宽高比等三维折线边坡几何参数对稳定性系数的影响并绘制了相关图表。结果表明,就凸状折线边坡而言,稳定性系数随着上坡角增大而减小,随上级高度系数增大而增大;当宽高比小于4时,三维效应对边坡稳定性系数有较大影响;边坡稳定性系数随加筋强度系数增大而直线增大,采用加筋层提高边坡稳定性效果显著。

Upper Bound Limit Analysis for 3D Reinforced Slope with Broken-line Sliding Plane

Based on the upper bound theorem of limit analysis, a rotational failure mechanism was established for the three-dimensional reinforced slope with broken-line sliding plane. The analytical expressions for internal energy dissipation and external force power were derived with effects of geometrical parameters of slope on the slope stability coefficient taken into consideration, such as strength coefficient of reinforcement, horizontal seismic coefficient, height coefficient, slope angles, width-to-depth ratio. Based on the plotted graphs, it is found that as for slopes with broken line in a convex shape, the stability coefficient decreases with an increase in the upslope angle, and increases with an increase in the height coefficient of upper step of slope. The stability coefficient of slope was closely related to the three-dimensional effect when the width-to-depth ratio was less than 4. It is shown that the stability coefficient increases linearly with the increasing of strength coefficient of reinforcement, indicating that slop stability can be greatly improved by placing layers of reinforcement.