斜倾厚层岩质滑坡视向滑动的土工离心模型试验  

CENTRIFUGE MODELING OF APPARENT DIP SLIDE FROM OBLIQUE THICK BEDDING ROCK LANDSLIDE

作　　者：冯振[1] 殷跃平[2] 李滨[1] 闫金凯[1] 

机构地区：[1]中国地质科学院地质力学研究所国土资源部新构造运动与地质灾害重点实验室,北京100081 [2]中国地质环境监测院,北京100081

出　　处：《岩石力学与工程学报》2012年第5期890-897,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金："十二五"国家科技支撑计划项目(2012BAK10B01);中国地质调查局地质调查工作项目(1212011140011)

摘　　要：采用石膏、水泥和重晶石按一定比例混合水,制作包含4组结构面的地质力学模型,利用土工离心机进行物理模型试验,研究斜倾厚层岩质滑坡视向滑动机制。离心模型试验成果表明,鸡尾山滑坡视向滑动的主要原因是软弱夹层软化与关键块体失稳,与地质调查结论一致。随着离心加速度的逐级增大,驱动块体首先达到极限平衡,随后进入蠕滑变形阶段,挤压前缘关键块体。当离心加速度达到16.2 g时,关键块体瞬时失稳发生视向滑动,引起斜坡整体失稳。土工离心模型试验结果重现了斜倾厚层岩质斜坡视向滑动的"后部块体驱动-前缘关键块体瞬时失稳"模式。An experimental investigation into mechanism of apparent dip slide from oblique thick bedding slope failure is performed through geotechnical centrifuge modeling test. The model is casted by mixture of gypsum, cement and barite and consists of four sets of joints. Agreements are obtained between field investigation and centrifuge test that weak layer softening and key block failure are the main reasons why Jiweishan landslide occurs. Driving blocks reach equilibrium and then start to creep crushing on key block in front as centrifugal acceleration rises. Finally, rock slope model fails instantaneously when centrifugal acceleration reaches 16.2 g. The key block fails in shear abruptly and slides in apparent dip followed by high-speed slide of driving blocks. The results of this experiment validate and reproduce the driving-blocks-and-key-blocks mode of apparent dip slide from oblique thick bedding rock slope failure proposed by previous studies.

关 键 词：边坡工程 离心机 关键块体 驱动块体 视向滑动 斜倾厚层岩质斜坡 

分 类 号：P642[天文地球—工程地质学]