Simulation Of Concrete Failure Process Using Discrete Element Method Based On 2-D Particle Flow Code

Concrete material is the most widely used material in construction. Profound research about failure process of concrete has been made by many scholars. Among the current study of concrete failure process where finite element method is applied, many of them simplify concrete material as homogeneous material, which can not reflect correctly the heterogeneity of concrete material, or study about the whole process of concrete material failure due to cracks, propagation and coalescence under the effect of load action. In this paper, in view of the defects of FEM in the numerical simulation analysis of concrete failure, concrete is considered as two-phase composite material combined by cement mortar matrix and aggregate. Research is carried out with the help of particle flow theory.1.In this paper, based on the given model dimension, a meso-level numerical model is built using the random generation of concrete aggregate from Clump Theory in PFC2D.2.An analysis of the effect of particle micro parameter variation on the macro-nature of concrete is made through the biaxial simulation test of concrete. The relation between macro-parameter and micro-parameter of material is built, which provides a basis for the parameter determination of concrete uniaxial simulation test.3.The whole failure process of concrete under the effect of uniaxial compressive load action is simulated. An analysis of the effect of particle micro parameter variation on the macro mechanical behavior is made. The scale effect of model is also studied. And simulated three-point bending test of concrete, given the failure process of the specimens map and the load- displacement curve.