Experimental analysis of CFRP laminates subjected to compression after edge impact

Abstract

Composite structures are particularly vulnerable to impact which lowers drastically theirs residual strength. In particular, the edge impact on composite stiffener is known as a critical factor on the loss of residual compression strength. At the same time, manufacturing of stiffened panels and achievement of experimental tests, of edge impact and compression after edge impact (CAEI) with stiffened panel, are particularly complex and costly. Then an experimental test set up has been designed to easily study the edge impact and the CAEI without complex specimen. It avoids the complex manufacturing of stiffener panels and avoids the use of high capacity machine. The mean goal is to define a new design method to improve the edge impact damage tolerance.Then experimental analysis of CAEI has been carried out on carbon fibre reinforced plastic (CFRP) laminates. This paper presents these results in order to determine the residual properties of the structure and to elaborate the failure scenario. It seems that a propagation of a compressive fibre failure plays a major role in the mechanisms that drives the laminate residual strength after edge impact. The good agreement of an open hole model with point stress approach seems to confirm the major role of the compressive fibre failure in the final failure.