Prediction Of The Mechanical Behavior Of Fiber-reinforced Composite With Domain Decomposition Method

Due to light quality, high specific strength, high specific modulus，excellent fatigue resistance and easily manufactured and shaped, compositesespecially woven fabric composites are widely used in aerospace, marine,automobile as well as civil architectural industries in the last decade.Because mechanical behaviors of fiber-reinforced composites largelydepend on its internal enhancement structure, it should be accuratelypredicted by material parameters of constituent before putting into practicalapplication. Using finite element techniques to predict the elastic properties ofthe composite material by create unit cell of fiber-reinforced composite havebecome a more practical approach. However, internal structure offiber-reinforced composite is highly non-uniform; it is difficult for unit cell tocontain every detail of the composite. And shape of matrix domain in unit cellis irregular which takes a lot of computer resources to calculate the base-bodyregion, also it is difficult to ensure good link between the fiber nodes and thematrix nodes.In this paper, the domain decomposition method was proposed for thestudy of mechanical properties of fiber-reinforced composite. The domaindecomposition method was different from traditional Represent VolumeElement method. Instead of modeling the fiber and matrix domains explicitlyin traditional Represent Volume Element method, Domain DecompositionMethod separately modeled the global domain and fiber domain which can beeasily discretized using the traditional solid element. Global domain wassuperimposed by fiber domain and matrix domain. The two domains weresuperimposed by coupling them with multi-point constraints from commercial finite element package MSC. Nastran. Multi-point constraints establisheddisplacement function to simulate coupling between fiber domain and globaldomain. Domain Decomposition Method is easier to set up models of WFCthan traditional Represent Volume Element method.The domain decomposition method was used for prediction of themechanical behavior of fiber-reinforced composite lamina T300/BSL914Cepoxy and AS4/3501-6epoxy. The numerical results show, mechanicalproperties of fiber-reinforced composite predicted by Domain DecompositionMethod correlate very well with the experimental data. Domaindecomposition method can not only greatly simplifies the modelingcomplexity of fiber-reinforced composite, but also can accurately predictmechanical properties of fiber-reinforced composite. Otherwise, the tendencyof mechanical properties under different fiber volume fraction offiber-reinforced composite was also coming into investigation. With theincreasing of fiber volume fraction, the mechanical constants E_x、E_z、G_xy、G_xzof fiber-reinforced are increasing, while Poisson’s ratios are vzxdecreasing.The domain decomposition method was also used for prediction of themechanical behavior of2D woven fabric composite （WFC）. DomainDecomposition Method is easier to set up models of WFC than traditionalRepresent Volume Element method. Numerical simulations show that theresults predicted by Domain Decomposition Method correlate very well withthe experimental data. The tendency of mechanical properties under differentfiber volume fraction of WFC was also coming into investigation. With theincreasing of fiber volume fraction, the moduli E_x、E_z、G_xy、G_xzof WFC areincreasing, while Poisson’s ratios vxy、vxzare decreasing.