Effect of T-stress on damage zone size predictions of notched laminated composites

In this article, the influence of T-stress on the plastic/damage zone size of a precracked isotropic/composite plate is studied by using various failure criteria under tensile loading conditions. The results of this study indicate that the stress field with T-stress always yields a larger damage zone than the field without T-stress. Using experimental data for a symmetrical, generally orthotropic graphite-epoxy laminate, the damage zone sizes predicted by the average stress criterion and point stress criterion as well as the D-criterion are compared. Experimental measurements of crack-tip damage zone size are used to establish a physical reference point by which all the theories are compared.