局部高陡边坡对排土场整体稳定性的响应规律

Response of Locally High and Steep Slope on Overall Stability of Waste Dump

采用现场调查和数值分析相结合的方法,基于简化Bishop法极限平衡理论,对排土场4个边坡剖面分别考虑正常、暴雨和特殊3种工况,共进行24次边坡静力和地震动力稳定性计算分析,并以安全系数表征。根据排土场安全度,分3种计算工况提出了稳定性分级标准,在此基础上预测了临界安全系数值对应的总边坡角。结果表明:局部高陡边坡对边坡整体稳定性的影响主要发生在暴雨和特殊工况下,正常工况时影响不大;数值计算得出的最危险滑动面均发生在过高和过陡的局部台阶位置,与现场勘查结果吻合;当前边坡总坡角每上升2°,安全系数平均降低了一个等级。

The field investigation and numerical analysis were used as the research methods. Three conditions for four slope sections of waste dump were considered, including normal, inclement and special conditions. And the stabilities of slope static and earthquake dynamic were calculated and analyzed 24 times by limit equilibrium theory of simplified Bishop method, which used the safety factors to express. According to the safety degree of waste dump, the stability criteria of three conditions were proposed. Then, the total slope angles corresponding to the critical safety factors were predicted. The results showed that the influence of locally high and steep slope on the overall stability of slope mainly occurred in the inclement and special conditions, and little influence in normal condition. The most dangerous sliding surfaces ob- tained by numerical calculation all located in high and steep bench, and the results were consistent with the field survey When the total slope angle rose by 2 degrees, the safety fac- tor was reduced by a level.