Comparing Computational and Experimental Failure of Composites Using XFEM

Abstract

Fiber reinforced polymer (FRP) composites have been used as a substitute for more conventional materials in a wide range of applications, including in the aerospace, defense, and auto industries. Due to the widespread availability of measurement techniques, experimental testing of composite materials has outpaced the computational modeling ability of such complicated materials. With advancements in computational physics-based modeling (PBM) such as the finite element method (FEM), strides can be made to reduce the efforts required in building and testing future composite structures. In this work, the extended finite element method (XFEM) is implemented to model fracture of composite materials under quasistatic loading. XFEM is applied to a three-dimensional (3D) computational model of a carbon fiber/epoxy composite cylinder, in half symmetry, that is subjected to lateral compression between two flat plates. Independent material properties are instituted for each composite layer, depending on individual layer orientation. The crack path produced by the analytical results is compared to experimental testing of lateral compression of a composite cylinder. Fracture site initiation and growth path are consistent in both the experimental and computational results.