Relation Between Elastic Properties and Stress Intensity Factors for Composites with Rigid-Line Reinforcements

Stiffness and failure resistance are two properties of a composite material that are known to be difficult (if not impossible) to improve simultaneously. They are of a competing nature: while stiffness is an effective property of a homogenized microstructure, failure resistance is highly sensitive to local microstructural details. In the present work we establish a direct link between these two properties on the example of a composite material reinforced with rigid lines. More specifically, we relate rigid lines’ contribution into effective compliance to stress intensity factors at their tips. Such a link provides useful insights into the source of competition between stiffness and failure resistance and suggests a way to overcome this persistent trend.