基于应变率相关的非线性损伤模型在高拱坝横缝开度分析中的应用

Application of strain rate-dependent damage model in analysis of dynamic opening of high arch dam transverse joints

本文采用应变率相关的混凝土非线性损伤模型以及基于Lagrange乘子的点点接触直接刚度法,进行了同时考虑混凝土材料非线性以及拱坝横缝接触非线性的高拱坝地震响应分析。研究表明,由于在地震过程中的混凝土非线性软化以及局部损伤开裂的影响,非线性拱坝横缝的开度及分布与采用线弹性混凝土本构关系计算结果有明显的不同,这对于横缝止水的设置具有重要影响。

The seismic response analysis of a high arch dam is carried out, in which the nonlinear characteristics of concrete is modeled by strain rate-dependent damage constitutive relationship and the nonlinear contact of joints is simulated by direct stiffness method based on the Lagrange multiplier. The study shows that the nonlinear concrete model has great effects on the dynamic opening of the contraction joints due to the nonlinear softening and cracking, when the dam is subjected to intense earthquake. This conclusion obviously differs from the calculation result by means of linear elastic constitutive model.