Abstract: On the basis of the shear-lag theory‚a layered shear-lag model was established to study the multiple transverse cracks of the matrix in90°-ply for cross-ply laminates under tensile loads．The crack distance and crack density were then calculated while taking the residual thermal effect into account‚with the results fitting perfectly with the existing experimental values．Thus‚the correctness and reliability of the proposed model and method are further verified． The calculated results also show that the crack density is related to the applied stress in the far fields and that the greater the applied stress is‚the greater the crack density will be；and a cluster of saturation transverse cracks with equal interval distance in90°-ply emerges when the applied stress reaches or exceeds a certain value．

Key words: cross-ply laminate, multiple crack, crack density, shear-lag analysis