Re-use of this resource is governed by a Creative Commons
Attribution-
NonCommercial-ShareAlike 4.0 International
https://creativecommons.org/licenses/by-nc-sa/4.0/
This is how the stress on an
individual fibre varies with strain
This is how the stress on a matrix
on its own varies with strain
The composite stress is given by the rule of mixtures up
to εmu
\[ \sigma _{1} =f\sigma _{f}+(1-f)\sigma _{m}\]
Onset of matrix cracking
On exceeding εmu
matrix
crack growths lead to an
increase in strain at constant
composite stress.
If the fibres fracture before the entire load is transferred
to the fibres, then this is the composite failure stress. \[ \sigma
_{1u} =f\sigma _{fmu}+(1-f)\sigma _{mu}\]
Composite failure
But if the entire load is
transferred to the fibres
before fibre fracture, then σ1u
= fσfu