A three-dimensional analysis of edge effects in composite laminates with circular holes

Abstract A three-dimensional (3D) displacement approach is developed in order to account for 3D effects of stress concentration in critical areas of composite laminates (free edges, free and loaded holes, notches, etc.). A finite element procedure is set up both for monodimensional and for bidimensional elements. First the problem of interlaminar stress prediction in a composite laminate with straight free edges under uniaxial loading is critically examined. The stress analysis of a holed composite plate under in-plane action is then studied in the case of a free hole and of a loaded hole. The importance of stacking sequence and of some geometrical parameters, such as the radius to the thickness ratio R/h, on the stress field around the hole are also investigated.