Approximate Solutions for Stresses around Pin-Loaded Holes in Symmetric Composite Laminates

The knowledge of average in-plane stress field in the vicinity of the pinloaded holes is essential for predicting both the failure strength and edge effects of composite laminate pinned joints. In this paper, a simplified technique is proposed to approximately determine the distribution of in-plane stresses in pin-loaded composite laminates based on the values of stresses right at the pin-loaded hole edges using the Reissner variational principle. The research results show that the distribution of stresses can be represented in the forms of power formula or exponential formula, and the corresponding numerical results are in good agreement with the available experimental data.