Analysis Of Equivalent Mechanical Parameters Of Cement Base Material With Random Distributed Aggregate System

Cement-based materials are widely used in the construction of a class of composite materials.concrete,mortar is the most common cement-based materials,cement-based materials,mechanical parameters of its mechanical properties and performance are closely related.One of the keys to calculate the equivalent mechanical parameters of cement-based materials is to calculate the equivalent elastic modulus of cement-based composites.Asymptotic homogenization method(AHM)is a multi-scale mathematical method to solve the equivalent elastic modulus of composite materials.Based on the experimental data,this paper establishes a three-dimensional random aggregate distribution(RVE),the equivalent elastic modulus of cementitious material was calculated by AHM from the mesomechanical scale,and the influencing factors of the equivalent mechanical parameters of cement-based materials were studied.The main contents and main conclusions of this paper are as follows:(1)Based on the aggregate gradation and matrix geometrical information and mechanical parameters of the existing experiments,a three-dimensional RVE of aggregate distribution was established.The asymptotic homogenization analysis was used to calculate the equivalent mechanical parameters of RVE.The results of the classical literature are consistent.(2)The effect of particle grade matching on the equivalent mechanical parameters of cement-based materials was analyzed.The three-dimensional RVEs of the aggregate size distribution under normal distribution and uniform distribution were established at the same volume rate,and the equivalent mechanical parameters were calculated.The difference between the two distributions was not significant.(3)The influence of the constitutive relation of cement-based materials on the mechanical properties of the composites was analyzed.The difference between the mechanical properties such as the stress and strain of the concrete slab under the action of self-weight and uniform load is calculated.When considering the anisotropy of the material,the stress and strain and the deformation of the member are smaller than those of the same sex,but the difference is not significant.