小湾高拱坝上游坝踵人工短缝设置效果的深入分析

In-depth study on effect of the induced slit at the heel of Xiaowan high arch dam

在已有研究成果的基础上,对小湾高拱坝坝踵附近人工短缝的设置效果进行全面、深入分析。采用无厚度的接触单元模拟人工短缝的工作性态,坝体混凝土本构模型采用单轴等效拉伸软化模型,分别采用整体模型和子模型对不同人工短缝设置高程、不同的缝内水压力进行了比较分析。从运行期的整体仿真计算结果来看,小湾拱坝设上游人工短缝后,坝踵应力可以得到较大的改善,且对坝体的整体性影响较小。为了更加合理地评价高拱坝人工短缝设置的效果,建议同时考虑施工期和运行期的荷载进行综合分析计算,为小湾拱坝人工短缝的设计提供科学依据。

Effect of the induced slit at the heel of Xiaowan high arch dam is discussed in this paper based on recent study results. A no-thickness contact element is presented to simulate the work state of structure slit, uniaxial equivalent tension softening model is adopted as the constitutive model of dam concrete. The whole model and sub- model are adopted to perform FEM analysis for different structure slit by setting altitude and different water pressure in slit. The computation results during operation period show that the tensile stress on dam heel is released. Random cracks may be avoided. Structure slit has little influence on the wholeness of dam.