设缝高拱坝的整体安全度和破坏机理研究

Study on the integral safety degree and failure mechanism of high arch dam with joints

为探讨设缝拱坝的整体安全度和可能的破坏形式及破坏机理 ,对坝体混凝土、缝和坝基材料采用了不同的非线性材料模型 ,并用增大水容重和降低坝基交界面或缝面材料强度储备两种方法对未设缝高拱坝、设部分周边缝高拱坝和底缝高拱坝的破坏形式、过程进行研究。结果表明 ,三种坝型的整体安全度由大到小的顺序为 :未设缝拱坝、部分周边缝拱坝和底缝拱坝 ;破坏均是从坝体与垫座交界面上游侧开裂开始 ,向下游扩展 ,最终下游侧为屈服破坏。拱冠上、下游侧附近首先出现屈服 ,然后向下、向左右两侧扩展。

In order to explore the integral safety degree, probable failure type and failure mechanism of arch dam with joints, the different non linear material models were used for the concrete and joint of dam body and the dam foundation materials and two methods of increasing unit weight and reducing the material strength potential of the juncture face or joint face of dam foundation were adopted to study the failure types and failure process of high arch dam without joint or with partial peripheral joint or bottom joint. The study results showed that the failure starts from the upstream side of the juncture of dam body and cushion base to the downstream side and finally the downstream side forms yield failure. In the vicinity of upstream and downstream sides of arch crest, the yield failure occurs firstly and then extends toward the down, right and left sides. The crack in the cushion base of arch dam with bottom joint is the most serious.