顺层陡倾岩质边坡倾倒模式试验  

Test study on the toppling mode of steep bedding rock slope

作　　者：王林康 郑子涵 章广成[1] 曾鑫 丁柄栋 崩兴涛 WANG Linkang;ZHENG Zihan;ZHANG Guangcheng;ZENG Xin;DING Bingdong;BENG Xingtao(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;Wuhan Hanyang Municipal Construction Group Co.,Ltd.,Wuhan 430050,China;China Energy Engineering Group Hunan Electric Power Design Institute Co.,Ltd.,Changsha 410007,China)

机构地区：[1]中国地质大学(武汉)工程学院,武汉430074 [2]武汉市汉阳市政建设集团有限公司,武汉430050 [3]中国能源建设集团湖南省电力设计院有限公司,长沙410007

出　　处：《地质科技通报》2025年第2期340-354,共15页Bulletin of Geological Science and Technology

基　　金：国家自然科学基金项目(41877263)。

摘　　要：在澜沧江中上游大华桥水电站的左岸分布着大量顺层陡倾岩质边坡,库区独特的工程地质条件为其提供了良好的变形孕育环境,因倾倒变形体失稳崩落形成的滑坡堆积物在库区分布广泛,这对水电工程的运行和维护造成了极大困难。为了研究顺层陡倾岩质边坡的演化过程、倾倒模式以及倾倒变形破坏机理,以库区左岸微风化板岩为参照原型配置相似材料,采用室内底摩擦模型试验方法,分析不同坡角、层面倾角、结构面产状条件下边坡的变形破坏特征。结果表明:①顺层陡倾岩质边坡主要倾倒破坏模式为拉裂−倾倒式,在演化初期坡脚处岩体由于应力集中最先发生弯曲变形,并由坡体前缘逐渐向中后部发展,坡表中部的岩体也逐渐由顺倾转变为直立至反倾状态,并在重力作用下加速向临空面方向弯曲倾倒,当变形到达一定程度时将沿着最大弯曲部位或结构面发生拉裂折断,最终岩块将会沿着拉裂面产生滑移甚至崩落。②通过对比试验模型的坡体参数及变形特征,将7组模型边坡大致分为3类:近直立顺层岩质缓坡、陡倾角顺层岩质陡坡、近直立顺层岩质陡坡。相较于坡角,岩层倾角对顺层陡倾岩质边坡倾倒变形破坏的影响更大;非垂直于层面的缓倾结构面比垂直于层面的结构面更容易引起顺层陡倾边坡的倾倒变形破坏,且相较于外倾结构面,当坡体发育内倾结构面时发生倾倒变形破坏的规模更大。③从变形阶段的角度将斜坡的变形演化过程划分为初始变形阶段、倾倒变形阶段、倾倒破坏阶段。④从机理上将顺层陡倾岩质边坡发生倾倒变形破坏的过程划分为应力调整阶段、弯曲−蠕变阶段、弯曲−拉裂阶段、倾倒−崩滑阶段;根据倾倒区的变形程度将变形破坏后的斜坡划分为强倾倒区、弱倾倒区和稳定区。研究成果可为顺层陡倾岩质边坡的演化过程、倾倒模�There are a large number of steep bedding rock slopes along the left bank of Dahuaqiao Hydropower Station in the middle and upper reaches of Lancang River.The unique engineering geological conditions in the reservoir area provide a good breeding environment for deformation.The landslide deposits formed by the collapse of the toppling deformed body are widely distributed in the reservoir area,which causes great difficulties for the operation and maintenance of the hydropower project.[Objective]In this paper,in order to study the evolution process,toppling mode,toppling deformation and failure mechanism of steep bedding rock slope,[Methods]we used the slightly weathered slate on the left bank of the reservoir as a reference prototype for the similar material material,then we choose to use the bottom friction test method to analyze the deformation and failure characteristics of slope under different condition of slope angles,plane inclination angles and structural plane occurrences.[Results]The results show that:①The main toppling failure mode of the steep bedding rock slope is the tensiletoppling type.In the early stage of evolution,the rock mass at the foot of the slope is the first to topple due to stress concentration,and gradually develops from the front edge of the slope body to the middle and back.The rock mass in the middle of the slope surface also gradually changes from the forward dip to the upright to the reverse dip state,and accelerates to bend and topple towards the free surface under the action of gravity.When the deformation of rock mass reaches a certain extent,it will fracture along the maximum bending part or structural plane,and eventually slip along the tensile fracture plane or even collapse directly.②By comparing the slope parameters and deformation characteristics of the test models,the 7 groups of model slopes are roughly divided into 3 categories:near-vertical bedding rock gentle slope,steep dip bedding rock steep slope,near-vertical bedding rock steep slope.Compared with slope Angle,t

关 键 词：顺层陡倾岩质边坡 相似材料 底摩擦模型试验 倾倒模式 倾倒变形破坏 

分 类 号：TV223.3[水利工程—水工结构工程]