四川梓潼金龙村边坡地震稳定性分析

Analysis on slope seismic stability assessment of Jinlong Village in Zitong of Sichuan

金龙村边坡位于四川省梓潼县境内,汶川县东,距离汶川地震中心约150 km。通过现场调查,分析了地形、地貌条件和地震等因素对该边坡稳定性的影响。发现滑动面位于土层与基岩的接触面,采用极限平衡法和数值分析法对边坡的稳定性进行了计算,2种计算得到的稳定性结果较为接近。采用动力时程分析法计算得到了边坡位移与加速度变化的关系。

Jinlong Village landslide was located in Zitong County,Sichuan and approximately 150 km east of Wenchuan. Field investigations indicated that the slope deformation was caused by the combined effects of unfavorable topographic and geological conditions and earthquakes. The sliding surface was along a contact between silty clay and mudstone. Wenchuan earthquake accelerated the creep,causing bulging of the ground surface. The factors of safety（ FOS） were calculated using the limit equilibrium method（ LEM）and the method of fast Lagrangian analysis of continua in 2 dimensions（ FLAC）. The results using the LEM indicated that the stability was clearly affected by seismic shaking,and when the PGA grew to 0. 08 g,the slope reached the limit state. The shear failure surface given by numerical simulation developed on the contact between the clay and silty mudstone,which confirmed the assumed the location of sliding surfaces using LEM.