モードIIき裂を有する長繊維強化複合材料の弾性応力分布のメゾメカニックス解析

抄録

The boundary element method was used to determine the elastic stress distribution near the tip of a delamination crack in fiber-reinforced plastics (FRP). FRP composites were modeled by a two-dimensional laminated structure composed of an isotropic matrix and orthotropic fiber. A mode II crack was induced in the matrix parallel to the fiber direction. The stress intensity factor. K₁₁, and the energy release rate, G₁₁, under mode II in-plane shear loading were calculated for the above inhomogeneous model, and compared with those for a homogeneous model. For long cracks, the energy release rate for the inhomogeneous model was equal to that obtained for the homogeneous model. For short cracks, the energy release rate was larger for the inhomogeneous model than for the homogeneous model. The characteristics of the elastic stress distribution ahead of the tip of a mode II crack in the matrix were compared with those of the elastic stress distribution for a mode I crack.