Probabilistic Finite Element Analysis of ASTM D6641 Compression Test for Marine Grade Polymer Matrix Composites

Abstract

The variability of compressive mechanical properties of a polymer matrix composite material with woven fabric reinforcement is studied using both experimental work and numerical simulations. Four E-glass/vinyl ester composite plates were fabricated using the vacuum-assisted resin transfer molding (VARTM) by a US Navy contractor. The materials and process selected are representative of marine grade composites typically used by the US Navy. Standard ASTM D6641 coupons were obtained from the plates and the laboratory results were compared with those of a 3D probabilistic finite element analysis (FEA). In the probabilistic FEA model, elastic properties, strength parameters and geometric properties of the woven fabric E-glass/vinyl ester coupons were considered as random fields, and generated using Monte Carlo simulations. The study evaluates the effects of spatial correlation, finite element size, probability distribution functions (PDF) types and failure criteria on statistical strength properties of the [0/90]2sf compression coupons. Comparisons of experimental and probabilistic FEA results provide useful information on how to assign mean, Coefficient of variance (COV) and PDF of material properties to individual finite elements within a mesh. The results are relevant in selecting proper test methods and developing design properties for these composites.