Study And Application On The Damage Constitutive Law For Concrete

The study of the the failure of the concrete constitutive structures has been developed greatly in the past two decades,and the study of the scholars has showed its superiority in the study of concrete stress.Therefore the constitutive law of the failure of concrete structures will be further studied in this paper on the basis of the basic knowledge of failure mechanics.The following study based on the basic knowledge of failure mechanics will be shown in this paper.Based on the mesoscopic model of the concrete damage,the damage constitutive relation of the concrete can be deduced,and the expression of stochastic damage will be built.For the convenience of research and calculation,the obvious expression of the constitutive law of the failure is deduced and the corresponding failure can be expressed by the experimental type of formula,which is the expression of the failure in concrete specification.To definite the constitutive law of concrete,the parameter must be standardized and the parameter of the constitutive law of concrete under uniaxial load should be defined.By arranging the experimental data of scholars at home and abroad,the parameter expression of high strength concrete and ordinary concrete is fitted,and then the unified constitutive law of concrete can be built.The accuracy and applicability of the unified constitutive law of concrete are shown by the full curve experiment of the high strength and the common strength concrete.Based on the mesomechanical model of stochastic damage constitutive model of concrete and the expression of stochastic damage in Chapter 2,the author choose the Hsieh-Ting-Chen strength control loading,and then build the convergence of constitutive law under uniaxial and biaxial load—equivalent strain of the energy in the stress space of strength control loading.The constitutive law of the failure of concrete under biaxial load is built by the equivalent strain of the energy.The accuracy and applicability of the unified constitutive law of concrete under biaxial load are turned up by the experiment by Kupfer.Based on the explicit damage constitutive relation and experimental damage expression,with various explicit expression in this paper,the author conduct the the calculation of the bearing capacity based on constitutive relation,the expression of failure strain,total stress and the point of the total stress,and then inferred the expression of bearing capacity in concrete compressive zone have been got,and then Strength formula under different stress be put forwarded.For appropriate reinforcement,exceed reinforcement and less reinforcement,the accuracy and applicability of the method in this paper are turned up by the comparison of calculation results with experiment.