The Effect of Temperature Gradient on the Free-Edge Interlaminar Stresses in Multi-Layered Structures

Abstract

For a multilayered anisotropic laminate, the intense and localized interlaminar stresses in the vicinity of a free edge may be significantly affected by non-uniformity of the temperature load. An efficient analysis method, based on polynomial expansions of the stress functions with respect to the thickness coordinate and the principle of complementary energy, is further developed in the present work to evaluate localized free-edge stresses under non-uniform temperature loads. The variational method yields closed-form solutions of the interlaminar stresses in terms of eigenfunctions. Interlaminar stresses are obtained for symmetric, four-layer, cross-ply and angle ply laminates subjected to a uniform temperature load and to linearly varying non-uniform temperature loads. It is shown that a temperature gradient may contribute significantly to the free-edge interlaminar stresses even if the local value of the temperature increment vanishes at the intersection of the interface and the free edge.