An investigation of the mechanical behavior of carbon epoxy cross ply cruciform specimens under biaxial loading

In this study, carbon epoxy cruciform type specimens with a cross-ply layup were biaxially and uniaxially in-plane loaded using four independent servo-hydraulic actuators. Four different biaxial loading ratios were investigated when the applied load was quasi-static. A comparison between experimental observations (for the damage and strain evolution of the biaxially loaded central section of the specimen) coming from digital image correlation measurements and a 3D finite element damage model will be shown. The symmetry and the uniformity of the strain field on the biaxially loaded zone were by the use of digital image correlation measurements investigated. Furthermore, the failure loads coming from the load cells of the machine were straightforward compared with the output of the finite element damage model. POLYM. COMPOS., 31:1554–1561, 2010. © 2009 Society of Plastics Engineers