Researchs On HJC Dynamic Constitutive Model For Concrete

In recent years, there are many domestic and abroad scholars have made a lot of study on the issues of dynamic response of concrete under the conditions of high pressures,high strain rates and large strains. With the rapid development of the modern technology , especially the finite element analysis technology and high-speed computers, the computers have been wild used to the numerical simulation analysis of the impact of concrete.First of all, the progress of the study on the dynamic compression mechanics properties of concrete are introduced briefly in the article, it also stated the problems of SHPB experiment of technology and theory and the methods of the finite element theory and the numerical simulation.One of the key points of the article is by using the explicit dynamic finite element software LS-DYNA, the numerical simulation on SHPB tests of concrete are carried out with Holmquist-Johnson-Cook(HJC)dynamic constitutive model. The HJC model of yield surface equation, the mechanism of constitutive, the material constants and the failure type f_s have been discussed. We have a clear understanding on the theoretical framework and the mechanical characteristics of the material constants of the HJC dynamic constitutive model.Another key point of the article is simulating the actual concrete model shock compression experimental results with HJC model, and by the numerical simulations on C60V0 series of concrete at different strain rates with the HJC model, to get the material constants and the determination methods of constants of HJC model. At last, the accuracy of the simulation combined with the experimental incident wave, reflected wave and transmission wave shape is verified.