Experimental and Modeling Study of Open-Hole Composite Laminates Under Tension

To study the failure behavior of open-hole carbon/epoxy composite laminate under tension, six pieces of open-hole composite laminates are tested, and the tension failure strength of every composite laminate is evaluated. Failure strength and damage phenomena of all composite laminates are examined. For all composite laminates, the failure phenomena is that the crack crosses the center hole transversely. The damage diffuses at the edge of the laminate composites. The main failure mode is fiber fracture and matrix cracking, with only a few delaminations. According to the experimental phenomenon, Hashin failure criteria and a stiffness degradation method are proposed to analyse the damage initiation and evolution of composite laminate. Finite element model is also established to simulate the failure propagation process of composite laminates. Compared with experimental data, a good agreement is achieved. Therefore, the finite element model established and the progressive failure method proposed in this paper can be applied to simulate the failure propagation process of composite laminates effectively.