设底缝对高拱坝工作性态的影响

本文用非线性有限元对小湾高拱坝(坝高292.0m)设底缝时的工作性态进行研究，模型中考虑了缝面应力与变位的非线性重调整，考虑了坝体、坝基材料非线性和底缝接触非线性的耦合，模拟了缝的开裂、滑移等非线性。对设缝深度、干缝、湿缝等对高拱坝拱冠、坝踵和坝肩等关键部位的位移场和应力场的影响进行了分析研究，并对设缝前后建基面、坝踵附近的开裂区和屈服区进行分析，研究结果表明，设底缝可以有效地降低高拱坝坝踵的梁向拉应力，对坝踵附近应力影响较大，坝体其它部位应力和位移变化不大。

Effect of base joint on performance of high arch dam

The nonlinear effect of base joint on the performance of Xiao-wan arch dam(292m high) is studied with nonlinear FEM. Nonlinear relationshipbetween stress and deformation on the joint surfaces and the coupling effect between the non-linearity of dam material (or foundation) and contact non-linearity of joint are considered. The non-linearity of the opening and slipping of the joint are simulated. The effects of joint depth and water pressure on stress and displacement field at critical locations, such as arch crown, dam heel and spandrel are analyzed. The effects of base joint on crack and yield area of dam foundation surface and vicinity ofdam heel are studied as well. It is concluded that with the base joint the cantilever stress at dam heel is effectively reduced, whereas the variations of stress and displacement at other locations are negligible.