Strength predictions of finite width composite laminates containing a central circular hole

The notched strength of a composite laminate containing a central circular cutout depends on material system, stacking sequence, hole size, and laminate width. Different layups and/or material systems may exhibit very different failure mechanisms. So far there are no globally accepted failure criteria developed for notched composite laminates. Four techniques of prediction of notched strengths of composite laminates are presented in this paper. Only the symmetric composite laminates containing one central hole under uniaxial tension are investigated in this paper. The techniques have revealed the influence of the variation of hole diameter-to-laminate width ratio (d/w) to the disparity of corresponding notched strength. It indicates that when d/w is greater than 0.3, the notched strength degrades almost linearly with increased d/w ratio. Good agreements have been observed between the proposed techniques and the test data adopted from literatures.