全级配大体积混凝土的内时损伤本构模型

复杂应力状态下全级配大骨料混凝土的强度和变形是混凝土坝体等大体积混凝土结构非线性有限元全过程仿真分析所必需的重要资料。本文结合内时理论和损伤力学理论，在大量试验数据的基础上，考虑尺寸效应和骨料湿筛效应对损伤变量的影响，建立了适用于不同骨料级配混凝土的内时损伤本构模型。该模型不仅摆脱了一般弹塑性中屈服面的概念，而且反映了不同骨料级配混凝土受力时不同的损伤演变规律。应用本文建议的模型，计算了全级配混凝土以及湿筛二级配混凝土在不同应力状态下的应力-应变关系，所得结果与试验数据符合的较好，可作为拱坝及其他大骨料混凝土结构设计的依据。

Endochronic damage constitutive model for fully-graded aggregate mass concrete

The behavior of deformation and strength of fully-graded stress state is the basis of nonlinear analysis and design for mass experimental data the endochronic theory is combined with damage aggregate concrete under complicated concrete structures. On the basis of mechanics to establish an endochronic damage constitutive model suitable for concrete structures with various gradations of aggregate. In the model the scale effect and influence of wet-screened aggregate are taken into account and the concept of yield surface is not necessary. It precisely expresses the evolution of damage in mass concretes with various gradations of aggregate. The proposed model is used to analyze the stress-strain relationships of fully-graded aggregate mass concrete and wet-screened concrete under various stress states. The calculation results are in good agreement with experimental data. It shows that this method is feasible for using as a guide for the design of arch dam and other mass concrete structures.