凸起地形对面板堆石坝面板应力变形特性的影响  

Impact analysis of convex terrain on stress-strain and deformation characteristics of CRFD

作　　者：李瑞平 徐建伟 刘啸宇 毛航宇 王柳江[1,2] LI Ruiping;XU Jianwei;LIU Xiaoyu;MAO Hangyu;WANG Liujiang(College of Water Conservancy and Hydropower,Hohai University,Nanjing 210098,China;International Joint Laboratory of Long-term Behaviour and Environmentally Friendly Rehabilitation Technologies on Dams,Hohai University,Nanjing 210098,China;POWERCHINA Huadong Engineering Corporation Limited,Hangzhou 311122,China)

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]大坝长效特性及环保修复技术中西联合实验室,江苏南京210098 [3]中国电建集团华东勘测设计研究院有限公司,浙江杭州311122

出　　处：《河海大学学报（自然科学版）》2023年第6期53-60,共8页Journal of Hohai University(Natural Sciences)

基　　金：国家重点研发计划项目(2022YFE0105000);国家自然科学基金青年科学基金项目(52209160,52009036)。

摘　　要：依托某建于凸起地形上的面板堆石坝,采用三维非线性有限元分析方法,研究左岸凸起地形及其2种开挖方案对面板堆石坝面板应力变形特性以及接缝变形的影响。通过坝轴向和顺坡向的面板挠度曲线解释了面板拉应力分布规律,提出了面板拉裂风险指标,并对开挖方案进行了效果评价。结果表明:凸起地形对面板应力变形和接缝变形有较大影响,相较于凸起地形完全挖除方案,凸起地形对堆石体和面板具有较强的约束和支撑作用,导致凸起地形处的面板坝轴向位移和挠度减小,拉应力区增大,垂直缝张开数量增多,然而,面板拉应力、垂直缝张开量以及周边缝张开和错动均有所减小;凸起地形上游侧按1∶1.5开挖后,面板变形协调性明显改善,面板拉应力区面积和垂直缝张开数量减少,有效降低了面板拉裂风险。To study the influence of the convex terrain in the left bank and excavation schemes on the stress-deformation characteristics of concrete slab and joints displacement of concrete face rockfill dams(CFRD),a three-dimensional nonlinear FEM analysis was conducted on a CRFD built on the foundation with local convex terrain.The distribution law of tensile stress on the concrete face was explained according to the deflection curves of concrete slab along the dam axis and the slope direction.Besides,the risk index of the concrete face cracking was proposed,which was used to evaluate the effect of excavation schemes.The results show that the convex terrain in the left side of dam has a great influence on the stress deformation of concrete slab and joints displacement.Compared with the completely excavated scheme,the convex terrain has the effect of constraint and support for rockfill materials and concrete slab in the left side of the dam,which leads to the decrease of the dam axial displacement and deflection of the concrete slab,increase of the tensile area of the concrete slab,and increase of the number of tension joints.However,the maximum tensile stress of the concrete slab,opening of the vertical joints,as well as the opening and dislocation of the peripheral joints are reduced.As the upstream side of the convex terrain excavated at the slope of 1∶1.5,the deformation coordination of the concrete can be improved.The tensile area and the number of tensile vertical joints are reduced,which can effectively reduce the risk of cracking of concrete slab.

关 键 词：面板堆石坝 复杂地形 面板应力 接缝变形 开挖方案 

分 类 号：TV641.4[水利工程—水利水电工程]