基于扩展有限元法的混凝土重力坝裂缝扩展仿真研究  

Simulation Study on Crack Propagation of Concrete Gravity Dams Based on Extended Finite Element Method

作　　者：张建伟 刘佳冰 黄锦林[2] 王勇 曹克磊 ZHANG Jianwei;LIU Jiabing;HUANG Jinlin;WANG Yong;CAO Kelei(School of Water Conservancy,North China University of Water Resources and Electric Power,Zhengzhou 450046,China;Guangdong Research Institute of Water Resources and Hydropower,Guangzhou 510635,China;Pearl River Water Resources Research Institute,Pearl River Water Resources Commission Guangzhou 510635,China)

机构地区：[1]华北水利水电大学水利学院,郑州450046 [2]广东省水利水电科学研究院,广州510635 [3]珠江水利委员会珠江水利科学研究院,广州510635

出　　处：《广东水利水电》2023年第5期8-14,共7页Guangdong Water Resources and Hydropower

基　　金：教育部重点实验室开放基金资助项目(编号:RMHSE1902);广州市科技计划项目(编号:2020-ky34)。

摘　　要：以坡月水库5#坝块为研究对象,采用扩展有限元法和水容重超载法对该坝块进行裂缝扩展仿真研究,探究该坝块的临界超载系数,研究重力坝坝踵部位裂缝扩展规律。结果表明:①5#坝块在满库水位下的水容重临界超载系数为1.4,可为坡月水库该坝块的极限承载能力提供参考依据。②大坝基本处于受压状态,仅坝踵周围和水力劈裂处产生拉应力,且最大拉应力均出现在坝踵部位。同一超载系数工况下,相同高程处的下游坝面位移比上游坝面位移大;坝体不同高程处的位移随高程的增大而增大;不同超载系数工况下,坝踵部位的拉应力、上下游坝面处的位移均随超载系数增大而增大。③裂缝扩展过程中,应力集中区沿裂缝扩展路径向裂缝尖端部位移动,当裂缝尖端的拉应力达到材料的抗拉强度时,裂缝继续扩展;当应力集中区移动到裂缝尖端且裂缝尖端的拉应力小于材料的抗拉强度时,裂缝停止扩展,研究成果可为重力坝坝踵部位裂缝扩展研究提供参考。Taking the 5#dam block of Poyue Reservoir as the research object,the fracture growth simulation study of the dam block was carried out by the extended finite element method and the water bulk density overload method,the critical overload coefficient of the dam block was explored,and the crack growth law of the heel part of the gravity dam was studied.The results show that:①The critical overload coefficient of the water bulk density of the 5#dam block under the full reservoir level is 1.4,which can provide a reference for the ultimate bearing capacity of the dam block in the Poyue Reservoir.②The dam is basically in a compressive state,with only tensile stress generated around the dam heel and at the hydraulic fracturing point,and the maximum tensile stress occurs at the dam heel.Under the same overload coefficient working condition,the downstream dam surface displacement at the same elevation is greater than the upstream dam surface displacement;The displacement at different elevations of the dam body increases with the increase of elevation;Under different overload coefficient conditions,the tensile stress at the dam heel and the displacement at the upstream and downstream dam surfaces increase with the increase of the overload coefficient.③During the process of crack propagation,the stress concentration area moves towards the crack tip along the crack propagation path.When the tensile stress at the crack tip reaches the tensile strength of the material,the crack continues to expand;When the stress concentration zone moves to the crack tip and the tensile stress at the crack tip is less than the tensile strength of the material,the crack stops expanding.The research results can provide reference for the study of crack propagation in the heel of gravity dams.

关 键 词：混凝土重力坝 扩展有限元法 水容重超载法 裂缝扩展规律 

分 类 号：TV32[水利工程—水工结构工程]