Effects of laminate misalignment on macroscopic strength and microscopic damage development of plain-woven laminates

抄録

In this study, a multiscale damage analysis of plain-woven laminates with laminate misalignment is conducted based on the homogenization theory for misaligned internal structures developed by the authors. For this, the homogenization theory is reconstructed for plain-woven laminates with arbitrary laminate misalignment in two directions using a novel boundary condition for unit cell analysis. The Hoffman's failure criterion is then introduced into the theory to determine the failure of fiber bundles and a matrix material, and the damage modes. The damages are expressed as reduction of stiffness according to the damage modes. The present method can efficiently analyze the macroscopic strength and the microscopic damage development of plain-woven laminates with arbitrary laminate misalignment using only one unit cell. This method is then applied to the damage analysis of plain-woven E-glass/vinylester laminates with 13 cases of laminate misalignment including the non-misaligned case under on-axis uniaxial tension. It is shown that the laminate misalignment noticeably affects the macroscopic strength of the laminates, which is attributable to the difference in the microscopic damage development in the laminates depending on the misalignment.