Interlaminar Stresses in Composite Laminates -- A Perturbation Analysis,

Interlaminar stresses play an important role in the load transfer mechanism in composite laminates. Both numerical and experimental results have demonstrated that when a thin laminate is subjected to a uniaxial extension, there exist highly localized stress concentration regions near the free edges, the so-called boundary layer regions. This phenomenon has been suggested to be the dominant factor initiating failure of some composite laminates. The present thesis will analyze the boundary layer by perturbing the exact elasticity equations with a stretching transformation. Solutions to these transformed equations provide a higher order analysis than idealized lamination theory. Hence better insight into the interlaminar stress behavior is obtained using the perturbation analysis. MM