Stochastic Damage Constitutive Law of Concrete under Uniaxial Compression

摘要

Based on the uniaxial tensile mesoscopic spring model of concrete, a uniaxial compression microscopic spring model is introduced. Considering the effect of material composition and horizontal deformation of concrete, a stochastic constitutive damage model of concrete is built. The effect of stiffness ratio on damage index is researched and the mechanism of fracture is studied. Based on the research of different failure modes of concrete with different strength grade, the stochastic damage constitutive equations of super high strength and high performance concrete, high strength concrete and normal concrete are built respectively to establish the unified stochastic damage constitutive model. Comparing with existing damage constitutive law and experiment results preliminarily, the feasibility of fractal damage constitutive law is verified.