基于尖点突变理论的拱坝安全性分析

Analysis of Safety Degree of Arch Dams Based on Cusp Catastrophe Theory

拱坝是空间高次超静定壳体结构,几何形状和边界条件都很复杂,较难确定其安全度.目前利用强度折减法分析拱坝安全性分析方法有三种,有限元数值迭代不收敛判据、特征点位移突变判据、广义塑性应变或等效塑性应变贯通判据.但上述方法主观影响较大.引入尖点突变理论,可以实现拱坝安全度的定量分析.结合三维有限元拱坝模型,利用有限元软件Abaqus计算坝体位移场,基于位移尖点突变模型得出该拱坝整体安全度为5.6,与传统方法得出的结论相一致.

An arch dam is a high-order statically indeterminate structure. Its geometry and boundary conditions are complex; so it is difficult to determine the safety degree. At present, there are three criteria for strength reduction finite element method widely used in the arch dam safety degree analysis, i.e. the non-con- vergence criterion of solution, the abruptness eritertion of the displacement at a certain characteristic location and the connectivity criterion of plastic zone. However, all these can be easily affected by subjective influence. By using cusp catastrophe theory, we can analyze the safety degree of arch dam quantitatively. With 3D finite element arch dam model, Abaqus is used to calculate the displacement field. Based on cusp catastrophe model of displacement, the safety degree is 5.6, which is consistent with the result from other methods.