Research Of Impact Fracture Of Laminated Glass Based On Intrinsic Cohesive Model

The automobile windshield is an important component of vehicle safety system.It is directly related to the safety and property of drivers,passengers and pedestrians.The head injury is the main cause of serious injury or death.Therefore,it is very necessary to investigate the impact fracture behavior of the automobile windshield under head impact.Recently,the impact fracture behavior of the automobile windshield is mainly investigated by experimental methods and numerical methods.For the numerical methods,different approaches have been to simulate the fracture of laminated glass,mainly including the DEM/FEM coupled method,the element deletion method,the extended finite element method and the cohesive model method,and so on.However,the traditional numerical methods such as the DEM/FEM coupled method,the element deletion method,the extended finite element method,as well as the experimental method are encountered some sticky problems.Therefore,in this work the intrinsic cohesive model methods and corresponding problems are studied systematically to research the impact fracture behavior of the automobile windshield.Firstly,a method to simulate the impact fracture process of laminated glass is presented in this paper.Based on the concept of the intrinsic cohesive model,the cohesive elements with zero thickness are inserted on the common surfaces of the finite elements of the glass plates prior to simulations.Besides,the difference between this MR model and another one commonly used MR model is investigated.Secondly,the impact fracture process of the laminated glass is simulated by using the commercial software ABAQUS,and the proposed approach is verified by comparing the numerical results with the corresponding experimental observations.Afterwards,parametric studies are performed to investigate the influence of the size of meshes,the cohesive penalty stiffness and the strength of glass.Following that,the effects of the stiffness of the PVB film,the support conditions and the thicknesses of glass layers on the impact fracture behavior of laminated glass,such as the impact force history,the crack patterns,the kinetic energy loss of the impactor and the kinetic energy loss ratio are investigated.Finally,a finite element model of the impact process between headform and windshield are established,and the acceleration curve and crack patterns which havebeen obtained through the numerical simulations are compared with the experimental observation,and the good agreement shows the feasibility of the proposed method.