地震作用下宝成铁路109隧道边坡失稳机理的离散元模拟  

Discrete element simulation of instability mechanism for 109 tunnel slopes of Baoji-Chengdu Railway

作　　者：陈永明[1,2,3] 滕光亮[4] 石玉成[1,2,3] 强正阳 

机构地区：[1]甘肃省地震局(中国地震局黄土地震工程重点实验室),甘肃兰州730000 [2]中国地震局兰州地震研究所,甘肃兰州730000 [3]甘肃省岩土防灾工程技术研究中心,甘肃兰州730000 [4]甘肃省建筑设计研究院,甘肃兰州730030

出　　处：《岩土工程学报》2013年第S1期23-32,共10页Chinese Journal of Geotechnical Engineering

基　　金：中国地震局兰州地震研究所地震科技发展基金项目(2012M05);国家自然科学基金项目(50878200)

摘　　要：以汶川地震触发的宝成铁路109隧道滑坡为例,在野外现场调查基础上,采用离散元数值模拟技术,输入实际记录地震波,对该边坡在地震作用下的动态响应及塑性区发展过程进行数值模拟,以研究地震作用下节理岩质边坡的失稳机理。并结合强度折减法,求出了在地震作用下该边坡的安全系数。分析结果表明:在地震作用初期,边坡表面出现拉破坏,并沿着坡面由边坡的下部向上部延伸,随着地震作用进行,拉破坏区逐渐向坡体内部发展,边坡下部的拉破坏区域逐渐扩大且向坡体上部发展,在地震作用后期,边坡表面存在着强烈的拉裂作用,当塑性拉破坏区发展到形成一个贯通的区域时,整个贯通区域上部的坡体便会发生滑塌破坏。Based on 109 tunnel landslides of Baoji-Chengdu Railway,the earthquake jointed rock slope instability mechanism is studied by using discrete element numerical simulation to simulate the dynamic response and the development process of plastic zone under earthquake action.The safety factor of the slope is calculated under earthquake action by using the strength reduction method.The results show that tensile failure occurs in the slope surface,and it extends from the lower part to the upper part along the slope in the beginning.Under the earthquake,the zone of tensile failure is gradually developed to the internal part of the slope,and the lower part of the tensile failure gradually expands and extends from the lower part to the upper part.There is a strong crack on the slope surface,and the rock slope will slump while the zone of tensile failure is formed.

关 键 词：地震作用 节理岩质边坡 失稳机理 强度折减法 离散元数值模拟 

分 类 号：U452.11[建筑科学—桥梁与隧道工程]