Effective Thermo-Elastic Constants Angle-Ply Laminates Containing 90 Degree Ply Cracks

Effective elastic moduli and thermal expansion coefficients for a composite containing transverse cracks through the middle layers are determined analytically. The laminate portion of the layered composite is treated as a single plate with effective properties (global laminate model), and the ply clusters are modeled as a homogeneous, orthotropic material (local model). The global model is a displacement based, higher order laminated plate theory, while the local model is a stress based homogeneous plate theory. Both models include the effect of transverse shear and normal stresses. This global/local scheme leads to considerable flexibility in modeling cracked laminates without resorting to an inordinate number of degrees of freedom. Numerical results are compared to other approaches.