| A Rayleigh-Ritz method is presented to determine the load or strain at which delamina-tion buckling will occur for a symmetrical composite laminate containing a single delamina-tion. This delamination is assumed to be elliptical in shape,with local axes of symmetrywhich may be at an angle a relative to the globle axes of the laminate. The laminate is suh-jected to complex loading,which include uniaxial and biaxial compression and shear. The crit-ical strain values of delamination buckling have been investigated for the delamination regionwith different a and ratio a/b of the major axis and the minor axis. The effects of possiblecoupling behavior of the delamination region have been considered. |