Analysis Of Concrete Meso Multi-field Coupling Damage At High Temperature

Concrete is widely used in current projects,and high performance concrete is replacing the traditional bridges,tunnels,high-rise buildings,offshore oil platforms and nuclear industrial concrete.Therefore,it is very important to predict the performance of high performance concrete structures.In this paper,the damage process of concrete under multi load field is studied from theoretical analysis,finite element simulation and practical measurement analysis.The main contents of the research are as follows:1.Under the microscopic analysis,the high temperature concrete is considered to be a porous multi-phase medium composed of solid phase and gas phase,and the conservation of energy and energy is used.A thermo mechanical coupled damage mechanics model of high temperature concrete is established,and the propagation and fracture process of multi field coupled damage of high temperature concrete materials are analyzed.Based on the model,the finite element program is compiled with the help of ANSYS platform,and the damage propagation process of the high temperature concrete field coupled with the force field is simulated and analyzed.2.The probabilistic failure model of concrete meso damage is established by using ANSYS platform.A program of two-dimensional and three-dimensional random probability distribution of concrete pores has been compiled to realize the random non interference distribution of the pores in concrete,and to analyze the formation of the sphere of the concrete material with initial micro defects and the distribution of the properties of the element material.3.The temperature field and the force field under different temperature conditions are used to calculate the field field coupling of high temperature concrete.The distribution of temperature field and stress field of concrete after pouring is studied in order to predict the possible location of damage and cracking of concrete and to analyze the failure propagation mode of concrete.4.The finite element analysis of high temperature concrete is carried out by using the coupled finite element analysis model of high temperature concrete porous coupling field.The calculated results are compared with the experimental results.On the basis of the thermodynamic coupling damage mechanics model of high temperature concrete,the finite element program compiled by the ANSYS platform can realize the damage expansion simulation analysis of the multi field coupling of the high temperature concrete,and the durability analysis of the high temperature concrete is explored.