强震作用下某不稳定斜坡变形机制分析

Analysis of the deformation mechanism of an unstable slope under strong earthquake

"5. 12"汶川大地震发生后,在地震灾区发育了1 700余处"裂"而未"滑""松"而未"动"的震裂山体,这对地震灾区人民生命财产安全造成巨大危害。本文以四川省某不稳定斜坡这一典型震裂山体为研究对象,基于现场调绘-概念模型的建立-变形破坏机制及模拟验证的基本技术路线,通过野外大量的地质调绘工作为基础,全面地研究了边坡工程地质条件、坡体结构特征、岩土体结构特征以及边坡变形特征等,在此基础上,通过对该边坡地质过程发展演化特别是地震发生后斜坡体内出现的变形破坏迹象进行机制分析,建立了其变形破坏机制的概念模型。最后运用FLAC^(3D)程序对提出的概念模型进行数值模拟分析,验证了概念模型的正确性以及参数取值的合理性。

There are about 1,700 unstable slopes(shattering mountains) appeared in the earthquake area after 5.12 Wenchuan earthquake,which cause great harm to the lives and property of the people in the earthquake areas.This article mainly studies an unstable slope-a typical shattering mountain in Sichuan province.Based on a large number of field geological survey,the structure characteristics of slope,rock and soil,the engineering geological condition and the slope deformation characteristics are fully studied in the basic technical route of field investigation to building conceptual model to simulation verification of deformation mechanism.Furthermore,the conceptual model of deformation and failure mechanism is built by analyzing the evolution of geological process,especially the signs of deformation and failure in the slope after the earthquake.At last,the correctness of the conceptual model and the rationality of the parameter values are verified by numerical simulation in FLAC^3D.