On the Modelling of Inelastic Interfaces in Fibrous Composites

Abstract

The classical fiber pull-out problem has been formulated in onedimension with a view to focus on the nonlinear interfacial response. The fiber and the cocentric matrix are assumed to behave elastically. The local interfacial bond-slip characteristic has been idealized to be elastic-linear softening. This greatly simplifies the otherwise implicit governing differential equation of the debonding process. Solutions to the fiber axial force and interfacial shear stress along the embedded length of the fiber have been obtained by applying appropriate boundary and continuity conditions. The stability of the debonding process has been investigated by varying the fundamental characteristics of the fiber-matrix interface, the fiber embedment length and the fiber diameter. The analytical model has been successfully used to predict many of the characteristics experimentally observed in fibrous composites that fail by fiber pull-out.