混凝土双轴拉-压综合随机损伤本构关系研究

STUDY ON SYNTHETIC STOCHASTIC DAMAGE CONSTITUTIVE RELATION OF CONCRETE UNDER BIAXIAL COMPRESSION-TENSION

实际工程中的混凝土结构大多处于复杂应力状态,该文考虑混凝土组成材料物理性能的差异及横向变形性等特点,基于混凝土单轴受拉弹簧-摩擦块细观单元,建立混凝土双轴拉-压随机损伤细观模型。在双轴拉-压荷载组合作用下,根据混凝土破坏过程中的能量守恒原理,分别建立超高强高性能混凝土、普通混凝土及高强混凝土综合随机损伤本构关系,并针对损伤本构函数进行多参数灵敏度分析。通过理论值与试验结果的比较,验证了提出的随机损伤本构关系的有效性。

Most concrete structures are in a complex stress state. Considering the effect of the material composition and horizontal deformation of concrete, a biaxial compression-tension microscopic damage model is introduced, based on the uniaxial tensile microscopic spring-friction block model of concrete. In the light of the energy conservation during the process of damage failure, the synthetic stochastic damage constitutive equations of super high strength and high performance concrete （SHSHPC）, high strength concrete （HSC） and normal concrete material subjected to biaxial compressive-stress are derived, and the sensitivity analysis results of the damage constitutive function are found. In order to testify the validity of the model, the calculated result is compared with the experiment data. It is shown that the model fits well with the experiment data.