A Numerical Simulation Method For Material Interaction Interface With Nonlinearity And Strain Rate Effect Consideration

In finite element(FE)numerical calculation,interface elements are commonly used to model the material interaction interface.Only with precise constitutive relationships,interface elements can represent the actual bond behavior of the material interaction interface.Furthermore,defining interface elements with precise constitutive relationships ensures that numeriacal results of the overall me chanical behaviors are accurate and reliable.The constitutive relationship of the bond behavior generally shows nonlinearity.Owing to the strain rate effect,the bond behavior of the material interaction interface under dynamic loading is different from that under quasi-static loading.However,there are few numerical studies on the material interaction interface which take the strain rate effect and the nonlinearity into consideration at the same time.Meanwhile,amongst all material models applicable to the interface element,there is no constitutive model that takes account of both nonlinearity and strain rate effect.Therefore,an interface material model subroutine considering nonlinearity and strain rate effect is developed in this study.In this paper,cohesive elements are slected to model the material interaction interface.A constitutive relationship for the material interaction interface has been proposed which considers both nonlinearity and strain rate effect.Based on cohesive elements and the constitutive relationship,an interface material model subroutine has been developed.A single cohesive element model is used to verify the accuracy of the developed interface material model in shear,normal and mixed mode.The static and dynamic shear tests of FRP to concrete interfaces are studied with the developed interface material model.At different loading rates,the FE results and test results of FRP strain distributions are in close agreement.The relative errors between FE results and test results of the ultimate loads are no more than 10%.It indicates that the developed interface material model can accurately represent nonlinearity and strain rate effect of the material interaction interface 's bond behavior.