Mechanical-property experimental study on stitching-reinforced composite member with a circular hole

The experimental study was carried out on the effect of stitching reinforcement to the member of composite laminates containing a circular hole. The effects of stitching parameters, such as stitching needle distance, row spacing, edge distance, single stitching and double stitching, etc., were compared and analyzed. The tensile strength was measured for the member of composite laminates containing a circular hole. The rules of strain concentration and strain distribution were investigated analytically and experimentally. The edge strain of the hole with the change of external loads was measured for different stitching parameters. According to the experimental results, a design method about stitching on the edge of a hole is presented.