混凝土重力坝三维数值模拟及优化设计

3D Numerical Simulation and Optimization of Concrete Gravity Dam

随着重力坝在工程中的广泛应用及新建重力坝坝高不断增加,其局部坝段的工作状况对大坝的整体运行影响也越来越大,因此选择适合工程实际的重力坝坝型显得尤为重要。通过抗剪断稳定计算和三维数值分析相结合的方法,分析了某重力坝的安全稳定性。计算结果表明,该坝坝肩段出现拉应力,以此对原设计方案进行优化设计,优化后新坝型坝肩段无拉应力出现。原方案与优化方案的对比分析表明:类似工程中,重力坝坝肩段设计应采用坝肩段与主坝段有一定角度或类似于拱坝的形式布设,以减小坝肩拉应力;在同类重力坝安全稳定分析时,可采用抗剪断稳定计算与三维数值模拟相结合的方法;在二维计算满足规范要求时,三维数值模拟可采用弹性材料计算。

With wide or range application of concrete gravity dam and the increasing of its height, the impact of working conditions in part of dam on the whole dam operation system is growing. Thus, gravity dam optimization design which aims to fit for engineering practice is particularly impor- tant. Based on a typical example of gravity dam, a new method that 3D numerical simulation combined with anti-cut stability analysis was employed to analyze the stability of that gravity dam. The calculation results indicates that tension stress appeared in abutment, hereof an optimization based on the original design is carried out, and the improved results shows that there is no tension stress in abutment. By comparing the original design and optimized design, conclusions are given as following： in order to reduce maximum tensile in abutment, concrete gravity abutment should be de- signed a certain angle with main dam or be designed similar to abutment of arch dam; the method of 3D numerical simulation combined with anti- cut stability analysis can be used in the analysis of congener gravity dam; when the results of 2D sliding stability analysis can satisfy eode＇s require- ments, elastic material can be used in 3D numerical simulation.