State-based Peridynamic Method For Nonlinear Behavior And Progressive Damage Modeling Of Composites

Fiber-reinforced composites was widely used in aerospace and other fields due to their excellent properties,followed by growing research demands on their mechanical properties.Existing composite modeling methods were usually based on classical continuum mechanics and had a fair accuracy,thus were adopted to solve engineering problems.But such methods still faced challenges in dealing with discontinuous problems.Alternatively,peridynamic theory,whose motion equation took the integral form,offered a solution way.This study focused on the modeling method of fiber-reinforced composites in state-based peridynamics.Discussion on the surface effects in state-based peridynamics was carried out.A compensation-modification method for nonlocal strain tensor was proposed to reduce the surface effects.Classical one-parameter nonlinear constitutive model was used to get the relationship between force vector state and deformation vector state.In order to describe the damage in state-based peridynamics,a scalar function was added in the equation of force vector state.Dynamic relaxation method was chosen as the numerical computation method.A computational software was developed under the developing environment of Microsoft Visual Studio 2010.The software mainly included a front processor and a solver.OpenMP and CUDA techniques were used for multi-threading parallel computing.A parallel computing method based on GPU for peridynamic model was studied,considering the widespread application of GPU parallel computing in large-scale computations.The calculation results of isotropic materials under tension and shear displacement field showed that,the proposed compensation-modification method could effectively reduce strain energy error of particles in the boundary region.Both unidirectional and orthotropic composite panels under uniaxial tension load were modeled.The resulting stress-strain curves fit well with the test data.Also,progressive damage analysis of composite panels with a center-hole was carried out,and the corresponding damage results agreed with the experimental and simulating results of a relevant research.The method for nonlinear behavior and progressive damage modeling of composites in state-based peidynamics was explored and verified.