Stress transfer in shear deformable discontinuous composites

Abstract

It is well known that the shear lag theory is not to provide sufficiently accurate strengthening predictions when the fiber aspect ratio is small. This is due to its neglect of stress transfer across the fiber ends and the stress concentrations that exist in the matrix regions near the fiber ends. In this paper, a new approach to investigate stress transfer mechanisms in shear deformable discontinuous composites is proposed to overcome the shortcoming of shear lag theory. The modification scheme is based on the replacement of the matrix between fiber ends with the fictitious fiber to maintain the compatibility of displacement and traction. Thus, the proposed model takes fiber end effects into account and results in fully closed form solutions. It was found that the proposed model gives a good agreement with finite element results and has the capability to correctly predict the values of interfacial shear stresses and local stress variations in the small fiber aspect ratio regime.