Numerical Research On Dynamic Mechanical Properties Of Concrete Based On A Local Concrete Damage Model

Concrete structures always subjected to dynamic loading except normal static loading conditons,such as seismic loading,wind,impact and blast.Due to the unpredictability and damage induced by these types of dynamic loaing,dynamic effects of concrete becomes one of the key factors affecting the design of concrete structures.Because concrete is strain-rate sensitive,so its material properties under dynamic loading are different from static state.Using static material properties to define the concrete material properties under dynamic loading can not properly predict the structure behaviours under dynamic loads.It's important to dicuss the dynamic constitutive models of concrete and its numerical application method.There are two types of way to introduce DIF into model based on the current research on finte element modeling of concrete structures under dynamic loading conditions.One is to ignore the strain-rate effect,and another is to directly introduce the DIF curve without any modification.Both of them can not accurately define the dynamic properties of concrete.The current research did review on the existing dynamic compressive tests,tensile tests and DIF curves on concrete,choosing a proper DIF curve for modeling research.Based on ANSYS/LS-DYNA together with K&C local concrete damage model,the compressive and tensile SHPB tests were modeled,and the numerical application issues regarding on the DIF curves of the concrete were discussed in detail.