Post-impact compressive strength of small composite laminate specimens

A miniature post impact compression test was used to study the post impact compression strength of small composite laminates technique for reducing the development cost and period of materials. This test method can be used in a material developing phase. Based on experimental studies, a reduced stiffness inclusion model was developed to predict the residual compressive strength of composite laminates after the low velocity impact. In this model, the damage was considered as a soft zone of the material. The damage zone was assumed to be circular. A finite element code with the 8-node 2D isoparametric element was programmed to compute the stress distribution. The point stress criterion was used to determine whether the post-impact laminates are compressed to failure or not. A good agreement between predicted residual compressive strengths and experimental results is obtained.