一种考虑波动效应的拟动力地震边坡稳定性分析方法  

Pseudo-dynamic Seismic Slope Stability Analysis Method Considering Wave Propagation Effects

作　　者：邓亚虹[1] 徐召 孙科 闫佐菲 DENG Ya-hong;XU Zhao;SUN Ke;YAN Zuo-fei(School of Geology Engineering and Geomatics,Chang an University,Xi'an 710054,Shaanxi,China;Aerial Photogrammetry and Remote Sensing Bureau,China National Administration of Coal Geology,Xi'an 710199,Shaanxi,China)

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054 [2]中国煤炭地质总局航测遥感局,陕西西安710199

出　　处：《地球科学与环境学报》2019年第5期623-630,共8页Journal of Earth Sciences and Environment

基　　金：国家自然科学基金项目(41772275);中央高校基本科研业务费专项资金项目(CHD300102268203)

摘　　要：考虑地震波在坡体内的传播特征,基于拟动力法,结合传统静力边坡稳定性分析极限平衡法(瑞典条分法),推导了边坡地震力公式和地震边坡稳定性安全系数公式。在此基础上,借助MATLAB软件开发了最危险滑面搜索和安全系数求解程序,实现了一种考虑波动效应的拟动力地震边坡稳定性分析方法。通过探讨地震动特性对地震边坡稳定性的影响,得到了地震边坡稳定性安全系数随地震动参数的变化规律。对于既定边坡,其安全系数随地震波初始相位呈现周期性波动变化,存在最小安全系数;并且此安全系数随地震系数和地震波波长与边坡坡高比的增大而减小。此外,从波动理论角度揭示了拟动力法与拟静力法的区别与联系,给出了两类方法的适用范围:当地震波波长与边坡坡高比大于10时,两类方法所得结果基本一致,均适用;而当地震波波长与边坡坡高比小于10时,拟静力法所得结果较拟动力法相对保守,仅拟动力法适用。Considering the propagation characteristics of seismic waves in slopes,based on the pseudo-dynamic method and the traditional limit equilibrium method(Felenius method)for static slope stability analysis,the formulas for calculating the seismic force of slopes and the safety factor of seismic slope stability were derived.On this basis,a program for the sliding surface searching and safety factor calculation,which realizes a pseudo-dynamic seismic slope stability analysis method considering wave effect,was developed by MATLAB software.By discussing the influence of earthquake motion characteristics on seismic slope stability,the variation law of safety factor of seismic slope stability with earthquake motion parameters was obtained.For a given slope,its safety factor fluctuates periodically with the initial phase of seismic wave,and there exists a minimum safety factor,which decreases with the increase of seismic coefficient and the ratio of seismic wave length to slope height.In addition,the differences and relationships between pseudo-dynamic method and pseudo-static method were revealed from the perspective of wave theory,which gives the applicable scope of the two methods.When the ratio of seismic wave length to slope height is greater than 10,the results obtained by the two methods are basically same and applicable;while the ratio of seismic wave length to slope height is less than 10,the results obtained by the pseudo-static method are relatively conservative compared with the pseudo-dynamic method,thus only the pseudo-dynamic method is applicable.

关 键 词：边坡稳定性 波动效应 拟动力法 拟静力法 地震系数 极限平衡 瑞典条分法 安全系数 

分 类 号：P642.2[天文地球—工程地质学]