Delamination buckling of stitched laminates can cause high interlaminar stresses which, in turn, lead to delamination growth. This study presents a three-dimensional model to analysis local buckling of stitched composite laminates with an embedded elliptic delamination near the surface. The effects of geometry parameters of ellipse and stitching thread on buckling loads are investigated by Rayleigh-Ritz energy method. The results show that stitching significantly improves critical buckling loads, the buckling loads increase rapidly with increase in equivalent elastic coefficient of stitching thread. The buckling loads are relatively large when the long axis of ellipse is vertical to the loading direction. With the increase in length of long axis, the buckling loads decrease and converge gradually.
GUI Liang-jin, YE Ning, LI Zheng-neng, KOU Chang-he.Study on Local Buckling of Stitched Composite Laminates with an Elliptical Delamination[J] JOURNAL OF BEIJING UNIVERSITY OF AERONAUTICS AND A, 2000,V26(6): 701-704