Peridynamic Modeling And Analysis Of FRP Laminates

The progressive damage analysis of fiber-reinforced plasticscontains various discontinuities such as damages, cracks, delaminations,fractures and penetrations. Conventional continuum mechanics theorieswhich were based on the partial differential equations of displacementoften had difficulties in solving discontinuous problems. Recently, a newsolid mechanics theory, Peridynamic Theory, whose basic motionequation was based on integration can avoid calculating the derivatives ofdisplacement in discontinuous areas. Therefore, it was highly appropriateto solve the discontinuous problems.At the beginning of this dissertation, the domestic and overseasresearch status, basic theory and numerical method of peridynamic theorywere briefly introduced.Then, a new method for progressive damage analysis offiber-reinforced composite laminates based on peridynamic theory wasproposed. According to the peridynamic theory, each node possessedinteractive connections with other nodes in a finite distance through socalled "bonds". The concept of off-axial modulus was introduced into thebonds’ definition which allowed bonds’ performance to vary with the angle between bond and fiber orientation, therefore, it could refined thecurrent depiction of anisotropy of composites. In this approach, the basicparameters, micromodulus and critical stretch, for peridynamic modelingwere deduced by introducing the concept of elastic deformation andmaximum strains in elasticity theory and composite mechanics. Threetypes of damages were analyzed: fiber fracture, matrix fracture anddelaminations.During this investigation, a numerical analysis software,PDynaComp v1.0, was developed based on peridynamic theory toanalyze the progressive damages in fiber-reinforced composite laminates.In the integrated development environment of Visual Studio2010, theperidynamic modeling and calculation program based on GPU parallelcomputing technology were coded by CUDA C. The code was optimizedby constant memory and structural data technology. It was able toimplement the peridynamic numerical analysis of composite laminates ona personal computer which contained a piece of CUDA graphic card.Compared with the conventional CPU computing, the calculationprogram obtained a great acceleration in the computational efficiencywhich was increased about78.3%. This analysis software had obtainedthe copyright authorized by National Copyright Administration of thePeople’s Republic of China.Based on this approach and analysis software, laminates with notch and open hole were analyzed under a tensile loading to simulate theprogressive damage process. The predicted elastic deformation, crackpropagation path and final failure mode had good agreements with resultsin literatures and experiments. They verified the correctness andeffectiveness of the method in this dissertation.This approach owned the abilities to thoroughly uncover the detailedand complex process of damage initiations and crack propagations incomposite structures. It was quite a method of potential for discontinuousproblems in composite structure’s analysis.