Three notable design strategies for manipulating failure modes in open-hole tensile composite laminates

Abstract Different failure mechanisms can lead to very different mechanical responses of notched composite laminates. We are trying to address two scientific problems: how can the occurrence of failure mechanisms be manipulated, and which kinds of failure mechanisms in open-hole tensile (OHT) tests can be manipulated to help improve the ultimate strength of composites? In this paper, three design strategies were proposed to manipulate the failure mechanism of notched composites: decreasing ply thickness at the ply level, hybridizing thin- and thick-ply laminates, and designing helical structures with variable pitch angles and ply thicknesses. Numerical methods are adopted to investigate the influence of the three design strategies on the failure mechanism of notched composites. These three design strategies are not limited to use in an OHT test. The results suggest effective methods for manipulating failure mechanisms to help create laminates with better mechanical properties.