关键词: 高混凝土坝, 渗透溶蚀, 长期变形, 环境损伤因子, 非定常时变本构模型

Abstract: To quantitatively analyze the effect of leakage dissolution on the long-term deformation of high concrete dams, we put forward the method of applying the performance evolution law of concrete obtained from indoor rapid dissolution test to the on-site concrete dam engineering with accumulated Ca²⁺ loss as the intermediate index. On this basis, we established the variable parameters-based time-dependent constitutive model for dam concrete considering environmental damage factor, and derived the expression of viscoelastic strain increment. Calculation result of a high concrete arch dam unveil that the leakage dissolution of dam concrete leads to the increase of annual extreme values of dam displacement as well as the amplitude between annual maximum and minimum values. After 100 years of leakage dissolution, the radial displacement of dam crest increases by 1.7%, while the ratio of fitting mean square deviation to maximum displacement obtained by HST statistical model of measured displacement is 2.1%, indicating that the long-term displacement increment caused by leakage dissolution is easily concealed by the fluctuation of environmental loads and monitoring errors. Therefore, when studying the long-term deformation of concrete dams, it is not necessary to independently consider the influence of dam concrete’s leakage dissolution; but more attentions should be paid to the abnormality of the temporal-spatial characteristics of dam deformation behavior.

Key words: high concrete dam, leakage dissolution, long-term deformation, environmental damage factor, variable parameters-based time-dependent constitutive model