ESTIMATION OF COMPOSITE STRENGTH BY A MODIFIED RULE OF MIXTURES INCORPORATING DEFECTS

Inadequacy of the rule of mixtures to estimate the true values of comp osite properties having a large concentration of defects has led to nu merous tests being performed costing time and money. Statistical avera ge of the properties from the Weibulls distribution law has thus been relied upon so far for the design of composite structures. Yet, to est imate the properties of a fibre reinforced composite material having s ufficient flaw densities due to the methodologies adopted for its proc essing, more so for fibres, has long been appreciated. To avoid this i nadequacy a modified rule of mixtures is developed incorporating defec t concentration in the fibre and matrix enabling to arrive at a more r ealistic value of the composite.