| An investigation was performed to study damage development in fiber-reinforced laminated composites induced by transverse concentrated loads. The objective of the study was to understand fundamentally the damage mechanics in terms of matrix cracking and delamination growth, and the interaction between them.;The study was focused on cross-ply laminates only. The load was introduced quasi-statically through a cylindrical or spherical indenter. The use of the cylindrical indenter simplified the damage pattern from three dimensions to two dimensions. Accordingly, the research was divided into two stages: (1) damage induced by a cylindrical indenter and (2) damage induced by a spherical indenter. Analytical models were developed for analyzing the damage induced by both loading conditions. The models consist of a contact analysis and a failure analysis. The contact analysis is essential for analyzing interface conditions of matrix cracks and delaminations and the contact condition between an indenter and a laminate. The failure analysis is required to determine initiation and propagation of damage induced by the indenters. Two-dimensional and three-dimensional nonlinear finite element analyses were developed based on the models proposed.;Results of calculations from the analyses were verified by experiments. The study characterizes the damage mechanics of composites and the material properties governing the crack initiation and growth behavior. |
