一种基于拟动力法和剩余推力法的地震边坡稳定性分析新方法  

A NEW METHOD OF SEISMIC SLOPE STABILITY ANALYSIS BASED ON PSEUDO-DYNAMIC METHOD AND RESIDUAL THRUST METHOD

作　　者：杨楠 邓亚虹[1] 慕焕东[1,2] 孙龙飞 蒋青江 钱法桥 刘凡 王梦晨 YANG Nan;DENG Yahong;MU Huandong;SUN Longfei;JIANG Qingjiang;QIAN Faqiao;LIU Fan;WANG Mengchen(Geology Engineering and Geomatics College,Chang an University,Xi an 710054,China;Xi an University of Technology,Xi an 710054,China)

机构地区：[1]长安大学地质工程与测绘学院,西安710054 [2]西安理工大学,西安710054

出　　处：《工程地质学报》2023年第2期607-616,共10页Journal of Engineering Geology

基　　金：国家自然科学基金(资助号:41772275);陕西省教育厅科学研究计划专项项目(资助号:20JK0801);陕西省自然科学基础研究计划一般项目(资助号:2022JQ-289);长安大学中央高校基本科研业务费专项资金(资助号:300102262505)。

摘　　要：由于常用的拟静力法存在诸多局限性,将更合理的拟动力法与边坡极限平衡分析法相结合对地震边坡稳定性分析具有重要的理论和实际意义。基于拟动力法与边坡极限平衡分析中的剩余推力法,推导了考虑振动放大效应的边坡地震力求解公式及地震边坡剩余推力计算公式。在此基础上,借助MATLAB软件编写了计算地震边坡剩余推力和安全系数的程序,得到了一种拟动力地震边坡稳定性分析新方法。应用已开发的程序,通过算例分析,讨论了地震动特性、坡体材料特性、坡体几何形状、地形放大效应对地震边坡稳定性的影响。研究表明:地震边坡安全系数随输入地震动的初始相位呈周期性波动变化,且土体放大系数不会改变其波动周期;地震边坡安全系数随地震系数、土体放大系数、地震动波长与坡高比值的增大而减小;当不考虑振动放大效应时,λ/H等于2是拟动力安全系数由急剧减小到趋于稳定的转折点,λ/H值越小,拟动力安全系数与静力安全系数越接近,λ/H值越大,拟动力安全系数与拟静力安全系数越接近;当考虑振动放大效应时,拟动力安全系数可能小于拟静力安全系数,因此,无论从安全还是经济的角度出发,拟动力法都比现行的拟静力法更合理,应该是地震边坡稳定性分析的首选方法。Due to the limitations of the commonly used pseudo-static method,combining the more reasonable pseudo-dynamic method with the slope limit equilibrium analysis method has important theoretical and practical significance for the analysis of seismic slope stability.Based on the pseudo-dynamic method and the residual thrust method in the limit equilibrium analysis,we derive the pseudo-dynamic seismic force calculation formula and the residual thrust calculation formula of the seismic slope considering the vibration amplification effect.On this basis,a program was compiled with the help of MATLAB software to calculate the residual thrust and safety factor of the seismic slope.A new method of pseudo-dynamic seismic slope stability analysis was obtained.Using the developed program,through the analysis of calculation examples,the influences of ground motion characteristics,slope material characteristics,slope geometry,and topographic amplification effects on the stability of seismic slopes were discussed.Research results indicate that the safety factor of seismic slope fluctuates periodically with the initial phase of the input ground motion,and the soil amplification factor does not change its fluctuation period.The safety factor of seismic slope decreases with the increase of the seismic coefficient,soil amplification factor,and the ratio of seismic wave length to slope height.Regardless of the vibration amplification effect,when the value ofλ/H is equal to 2,the pseudo-dynamic safety factor changes from a sharp decrease to a stable.The smaller the value ofλ/H,the closer the pseudo-dynamic safety factor and the static safety factor.The larger the value ofλ/H,the closer the pseudo-dynamic safety factor and the pseudo-static safety factor.When considering the effect of vibration amplification,the pseudo-dynamic safety factor appears to be smaller than the pseudo-static safety factor.Therefore,the pseudo-dynamic method is more reasonable than the pseudo-static method from the perspective of safety or economy,and it is

关 键 词：地震边坡稳定性 拟动力法 剩余推力法 振动放大效应 安全系数 

分 类 号：P642.22[天文地球—工程地质学]