Experimental Study On Complete Stress-Strain Curve Of Concrete Under Uniaxial Loading And Stochastic Damage Constitutive Model

The existing researches about constitutive theory of concrete are mainly focused on the ordinary concrete,but few researches about the fiber reinforced concrete or the sprayed concrete, and rarely consider the influence of the material composition and the construction process.The unified stochastic damage constitutive model which is established in this paper can analyze the concrete with different type by the choice of the distribution function.In this paper,the ordinary concrete,the steel fiber reinforced concrete,the polypropylene fiber reinforced concrete and the sprayed concrete were tested under uniaxial compressive loading about complete stress-strain curve whose original designing strength are C30.According to the experimental study,Analyzes the failure process of the concrete and the characteristics of the complete stress-strain curve,According to the test results,makes a statistical analysis of the characteristic parameters from the complete stress-strain curve(the peak stress,the peak strain, the elastic modulus and the ultimate compressive strain) of the different concrete,According to the K- S testing method,the characteristic parameters from the complete stress-strain curve obey the normal distribution,lognormal distribution,and the Weibull distribution,lays the foundation for the stochastic damage constitutive model.According to the theory of parallel bar model and the statistical analysis of the characteristic parameters from the complete stress-strain curve,this paper establishs the stochastic damage constitutive model which analyzes the concrete with different type. According to the test results,this paper determines the parameters of the stochastic damage constitutive model,makes a comparative analysis between the model results and the test results. By the study,Weibull distribution is suitable for the stochastic damage constitutive model of the ordinary concrete,the sprayed concrete,lognormal distribution distribution is suitable for stochastic damage constitutive model of the steel fiber reinforced concrete,the polypropylene fiber reinforced concrete.