INTERFACIAL DEBONDING AND FIBER PULL-OUT STRESSES OF FIBER-REINFORCED COMPOSITES .7. IMPROVED ANALYSES FOR BONDED INTERFACES

The previous analytical solution, which was presented in part I of this series of papers, for the transfer of elastic stress from a bonded fiber to the matrix is improved in the present study. The present analysis resolves the following limitations, which existed in the previous analysis. (1) The radial dimension of the matrix is much greater than that of the fiber. (2) The radial dependence of the axial stress in the fiber is ignored. (3) The approximate shear stress distribution, which is used to derive the radial dependence of the axial stress in the matrix, satisfies the free surface condition only in an approximate sense. (4) A plane strain condition is assumed in the equilibrium equation in order to relate the tangential stress to the radial stress at the interface. The most significant improvement of the present analysis is that it is applicable for any radial dimension of matrix.