Dilatation and through-the-thickness Poisson's ratio of composite laminates

In this paper an investigation of the through-the-thickness Poisson's ratio and the dilatation for a general class of randomly-oriented composite lami nate is presented. A simple random statistical analysis has been used to de monstrate that under certain conditions, for instance, a laminate with 40 p lies or more, the mean values of the through-the-thickness Poisson's ratio and the dilatation in the randomly-oriented laminate are close to those val ues evaluated from the analytical formulation. Also, the influence of the v arious lamina material properties E-2/E-1, E-3/E-1, G(12)/E-1, v(12), v(31) and v(32) on the through-the-thickness Poisson's ratio and the dilatalion of the laminate are obtained. The results from this statistical analysis pr ovide a set of general guidelines for designing the through-the-thickness P oisson's ratio and the dilatation of the composite laminates to meet variou s requirements in engineering applications.