Peridynamic Simulation For The Rate Effect Of Impact Damage In Composite Laminate

Fracture phenomenon of solid materials is one of the most difficult problems in the study of mechanics. The conventional continuum theory is ill-suited to such problems in that the partial derivative of the displacement field doesn't exist at the crack tip. Fortunately, The formulation of the peridynamic theory may overcome this difficulty.Peridynamics(PD) is a new nonlocal theory formulated by integral equations, which is promising for linking different length scales. It doesn't require spatial derivatives and extra fracture criterions as opposed to the classical continuum theory. Besides, the locations of the discontinuity are not required to be known previously. Therefore it is well-suited for discontinuous problems.In this paper, the development history and research status of PD theory and the rate effect phenomenon in composite laminates are firstly reviewed. Then, a PD rate-dependent constitutive equation is proposed based on the combination of the PMB model and the viscoelastic Kelvin-Voigt model. Next, the PD numerical method and software platform LAMMPS are introduced, and an algorithm is designed for the PD rate-dependent constitutive model. Later, a PD model for orthotropic lamina is proposed by means of the revised fiber bond and matrix bond and a composite laminate model is presented by introducing a new interlayer bond. Finally, a series of PD simulations for the composite laminates under various impact loadings are implemented based on the PD rate-dependent constitutive model and PD composite models. And some remarkable conclusions are obtained, which implies that PD theory is quite a method of potential for discontinuous problems in composite structures.