重庆南川甑子岩山体崩塌机制研究  

Failure mechanism on the Zengziyan collapse in Nanchuan of Chongqing

作　　者：冯振[1] 陈云霞[2] 李滨[1] 贺凯[1] 高杨[1] 朱赛楠[3] 

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]重庆市铜梁区国土资源和房屋管理局,重庆402560 [3]长安大学地质工程与测绘学院,陕西西安710054

出　　处：《水文地质工程地质》2016年第1期50-56,共7页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目资助(41302246;41472295);国土资源大调查项目资助(1212011220140;12120114079101)

摘　　要：本文以重庆南川甑子岩崩塌为例,对近水平厚层状高陡灰岩山体座落滑移式崩塌机制进行研究,通过工程地质分析揭示了甑子岩危岩崩塌的成因机制,利用数值模拟开展了初始变形破坏的研究。研究认为,甑子岩崩塌是自然条件下形成发育、受岩溶风化与人类工程活动影响所产生的大型危岩体崩塌。岩体中多组大型陡倾节理发育,卸荷作用下在陡崖边缘形成张拉裂隙,地下水长期溶蚀使裂隙连通率不断增大,地下采空加速软弱基座破坏、危岩体变形。随着裂隙的贯通,软弱基座内部应力累积,应变逐渐增大,当超过岩体强度时发生圆弧形剪切滑移破坏,导致柱状危岩体座落崩塌。Taking the Zengziyan Cliff as an example,the failure mechanism of rock collapse in an subhorizontal bedding limestone slope is studied. The failure mechanism is revealed on the basis of geological analysis and the initial failure process is reproduced with numerical simulation. The results show that the Zengziyan Cliff failure is a result of slope evolution,karstification,weathering and mining activity. Tectonic joints were developed in rock mass and tensile cracks were generated due to stress relief. Karstification and weathering make the cracks wider and deeper. In addition,the underground mining aggravated fracture of weak base and deformation of perilous rock. Stress accumulated in the weak base as the vertical back scarp went deep and rotational shear failure occurred when the stress exceeded the strength of weak base rock mass,leading to a rock collapse.

关 键 词：近水平岩层 崩塌 座落滑移 离散元数值模拟 

分 类 号：P642.21[天文地球—工程地质学]