Study of biaxial stress in rectangular patch-reinforced composites with elastic and damage interface

A two-dimensional (2-D) shear-lag model with an elastic and damage interface was developed to investigate stress transfer in rectangular patch-reinforced composites subjected to uniaxial or biaxial loads. The semi-analytical solutions of bi-directional normal stress and interface shear stress of the composites were derived. The effect of Poisson's ratio of the substrate, aspect ratio, interface thickness and elastic modulus of the interface on the stress of the composites was investigated. The stress distribution solutions of the 2-D model agree well with the finite element (FE) results. It provides an effective model for solving the 2-D stress problem in rect-angular patch-reinforced composites.