强震作用下层状岩质斜坡破坏的大型振动台试验研究  

Large-scale shaking table model test study on failure of layered rocky slope under strong ground motion

作　　者：邹威[1,2] 许强[1] 刘汉香[1] 陈龙[1] 王龙[1] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]中铁二院成都地勘岩土工程有限责任公司,四川成都610031

出　　处：《地震工程与工程振动》2011年第4期143-149,共7页Earthquake Engineering and Engineering Dynamics

基　　金：国家重点基础研究发展计划(2008CB425800)

摘　　要：以"5.12"汶川地震背景为基础,对不同岩性组合水平层状岩质边坡进行了大型振动台模型试验研究。文中介绍了振动台试验过程,通过对试验现象的观察处理分析,考察了边坡的破坏现象特征、变形破坏模式。实验结果表明,地震力作用下边坡的变形破坏程度、特征以及稳定性不仅与地震波的类型、加载方向、频率、振幅有关,同时还受边坡的岩体性质、高程、微地貌、结构面等地质因素控制,对于同一岩性组合边坡,在同种地震波和等振幅作用下,合成向ZX向、X向和Z向激振对边坡的破坏性依次增强;在等振幅和激振方向下,正弦波15Hz、10Hz和天然地震波对边坡的破坏性依次减弱;随着振幅增加,各种地震波对边坡的破坏程度加剧。水平层状岩质边坡破坏主要发生在顶部尤其是靠近坡肩部位,其破坏受层面控制。在地震作用下呈拉裂-剪切-滑移式破坏。在相同地震波作用下,上软下硬边坡先于上硬下软边坡破坏,大振幅作用时顶层岩体震碎呈散体状滑落,形成滑坡;而上硬下软边坡破坏主要是岩层后缘拉裂后整体剪切错动,最终形成崩塌。Based on the background of ＂5.12 Wenchuan earthquake＂,a large shaking-table model test was done to study the horizontal stratified rock slopes with different lithology.The process of shaking table test is introduced in this paper.Through observing,handling and analyzing the testing phenomenon,the failure characteristics and deformation failure of slope were studied.The results show that deformation failure degree,characteristics and stability of slope under seismic force not only have something to do with type,loading direction,frequency and amplitude of seismic ground motion,but also are controlled by some geological factors,such as rock nature,elevation,micro-geomorphology and structural plane of slope.Under the effect of same seismic ground motion,for the same rock slope,the destruction of synthesis of excitations in ZX-direction,X-direction and Z-direction at the slope became stronger successively.When the direction and the amplitude of the excitations were the same,the destruction of 10Hz,15Hz sine wave and natural seismic wave became weaker successively.As the amplitude increased,the destruction degrees of various seismic waves to the slope became stronger.The failure of stratified rock slope was mainly caused on the top,especially at the place close to the slope shoulder,and it was controlled by the layers in the way of tension-shear-slip.Under the same seismic wave,the failure of the slope,which was soft in the upper portion and hard in the lower protion,happened earlier than the slope,which was hard in the upper portion and soft in the lower portion.The rock on the top crept down in pieces under the effect of great amplitude vibration and then the landslide occurred.However,the failure of the slope,which was hard in the upper portion and soft in the lower portion,was sheared and dislocated as a whole after the crack of the rock stratum,and was collapsed finally.

关 键 词：振动台 岩质斜坡 边坡工程 边坡稳定性 物理模拟 

分 类 号：P315.972[天文地球—地震学]