Random-fractals-based Research On Tensile Mechanical Properties Of Concrete Numerical Meso-model

As a material widely used,research on the properties of concrete has always been an important research direction in the civil engineering discipline.Traditional studies are mostly focused on the macro scale,and the study of concrete as a homogeneous material is generally difficult to make a scientific and reasonable interpretation of the internal mechanism between the mechanical behavior and the form of destruction of concrete.To make better use of the material's effectiveness,this article studies the mechanical properties of concrete on the mesoscopic level,and treats concrete as a mixture of three components,aggregate,cement stone,and the interface between the two.Fully considered in the analysis The heterogeneity and physical randomness of concrete materials,study the basic mechanical behavior of concrete,and initially explore the internal mechanism of stress.In this paper,based on the measured fractal dimension of the meso-components of concrete,a meso-scale numerical model with the same fractal dimension is constructed to simulate the mechanical behavior of concrete under axial tensile load,and the effect of the meso-component fractal dimension on its mechanical behavior is studied.Influence law mainly completed the following research content:(1)Designed a set of numerical modeling methods based on fractal theory.First,based on the fractal theory,the Fortran language was used to establish the concrete aggregate generation model to ensure the randomness of the aggregate;then the Ansys finite element program was used to establish a numerical meso model of the concrete.The fractal dimension and coarse aggregate content were used to compare the concrete Make a quantitative representation of the geometric properties of(2)To obtain the mechanical properties of each component of concrete,the relevant material tests that have been completed in the previous period are adopted,and the experimental results are brought into the numerical model to give the element properties,and the failure criteria of different component materials in concrete are theoretically explained to Based on this,the algorithm program of concrete numerical model under axial tension was established;(3)The effect of fractal dimension on the mechanical behavior of concrete under axial tension is analyzed through the results of numerical simulation experiments.The elastic modulus,tensile strength,peak strain and different response laws of concrete under axial load are studied,and the effect of fractal dimension on the mechanical properties of concrete under axial load is investigated.The comparison of axial compression experimental data explores the internal mechanism of the fractal dimension affecting the macroscopic mechanical propertiesof concrete.