EFFECTS OF A FREE-EDGE DELAMINATION ON BUCKLING OF RECTANGULAR COMPOSITE PLATES WITH 2 FIXED LOADING AND ONE SIMPLY-SUPPORTED SIDE EDGES

An experimental and analytical investigation is conducted on the compr essive buckling behavior of an orthotropic plate with a free edge dela mination. The plate is a simplified model of stiffener plates. In the present paper two loading edges are fixed and a side edge is simply-su pported, The delamination locates at the free edge over the whole leng th. A Rayleigh-Ritz approximation method is adopted in the analysis. A constrained point is used to allow contacts between the two delaminat ed surfaces. At this point, relative displacement and two relative slo pes are constrained through imaginary springs. The buckling load of th e geometrically admissible buckling mode is obtained by an ordinary ei genvalue analysis. The analytical results are compared with the experi ment and the results agree well. The effects of the width and the loca tion of the delamination on the buckling behavior are studied analytic ally for the plates with various aspect ratios. Low local delamination buckling can occur at very low load when the delamination locates nea r the surface and its size is relatively large compared with that of t he plate. The constrained point is shown to be effective for the buckl ing analysis of the delaminated plates.