Fibre Reinforcement Effect in Composites with Frictional Interfaces

                                   by

                Natasha Movchan, University of Bath, UK

                  AEB350,  2:15pm Friday, May 31, 1996


                                Abstract

  The effect of fibre interaction on matrix cracking in a unidirectional
  fibre--reinforced composite is analyzed. It is assumed that the matrix
  material contains a crack in a plane perpendicular to the fibres.
  Fibres, remaining intact, debond from the matrix and then act as
  bridging ligaments in the crack wake. The debonding process is
  accompanied by frictional sliding governed by a Coulomb friction law.
  Fibres are considered to be randomly located in the transverse plane.
  The interfacial shear strength is taken to be relatively weak, and the
  length of the region where slippage occurs is considered to be large
  compared to the fibre radius. The debonding process is described with
  the use of the analytical approach based on the ensemble averaging
  procedure and the asymptotic analysis of a model problem for a single
  fibre in an ambient stress field due to the other fibres and applied
  load. A system of integro--differential equations is obtained for the
  jump of the longitudinal displacement across the fibre--matrix
  interface, the fibre axial stress and the length of the slipping zone.
  The dependence of the fibre axial stress on the relative fibre--matrix
  displacement is examined for different values of the volume fraction
  of fibres.

Requests for preprints and reprints to: movchan@math.utah.edu
This source can be found at http://www.math.utah.edu/research/