翠华山山崩地质遗迹景观离散元数值模拟  

NUMERICAL SIMULATION OF CUIHUA ROCK AVALANCHE WITH DISCRETE ELEMENT METHOD

作　　者：吕艳[1] 王根龙[2,3] 张新社[2] 

机构地区：[1]长安大学地球科学与资源学院,西安710054 [2]中国地质调查局西安地质调查中心,西安710054 [3]中国科学院工程地质力学重点实验室,北京100029

出　　处：《工程地质学报》2013年第3期443-449,共7页Journal of Engineering Geology

摘　　要：城市地质遗迹景观调查研究是城市地质工作的一项重要内容,而探索地质遗迹景观的成因则是挖掘其科学价值和实施保护措施的关键问题。以中国"山崩奇观"的翠华山山崩为研究对象,采用典型天然地震记录作为地震输入条件,借助离散元动力分析模块,对翠华山山崩的动力响应规律进行了数值模拟,再现了地震山崩的启动、加速、解体、堆积的全过程。研究结果表明:地震惯性力作用使山体质点加速度和速度产生放大效应,特别是山体顶部的动力放大效应最为显著,加速度放大系数达2.0;翠花山山崩具有高速远程的特点,其前缘的崩塌体最大水平速度达44m·s-1,崩落水平距离达460m,堵塞沟谷形成堰塞湖;地震山崩的整个破坏过程包括4个阶段,分别为启动阶段、加速阶段、减速阶段和堆积阶段。It is very important to investigate geological relics landscapes for urban geological work. The Cuihua rock avalanche is a marvellous spectacle of seismic avalanches in China. Based on dynamic discrete element method, the dynamic response and failure process are simulated under a typical natural earthquake loading. The failure process of Cuihua rock avalanche is reproduced with the numerical simulation. The following results are obtained. Firstly, the amplification effect of velocity and acceleration is the reason of earthquake inertia force. The maximum magnification factor reaches 2. 0 on the top of slope. Secondly, high speed and long run out are the characteristic of the rock avalanche. The results shown the maximum horizontal velocity reaches up to 44m. s-1 and the horizontal movement distance for some rocks reaches 460m at the front of the rock avalanche. Thirdly, the whole failure process include four stages： starting up stage, accelerating stage, decelerating stage and accumulation stage.

关 键 词：地质遗迹景观 离散单元法 地震山崩 动力放大效应 高速远程 

分 类 号：P315[天文地球—地震学]