Meso-scale strain localization and failure response of an orthotropic woven glass–fiber reinforced composite

The present work focuses on studying the multi-scale deformation and failure mechanisms of an orthogonally woven glass fiber reinforced composite as a function of fiber orientation angle using digital image correlation. The full-field displacement and strain localization are effectively captured at meso-scale. At continuum scale, a remarkable change in mechanical response is observed when the loading axis diverges from principal axes. The variation in the global mechanical response is observed to be most prominent in the change of stiffness and strain at failure. At meso scale, a high degree of local deformation heterogeneity is observed and the level of inhomogeneity is found to be more prominent in case of the 45° off-axis specimens. While fiber-pull out is the major failure mode in the case of specimen loaded parallel to 0° and 90° fiber orientation, the localized shear strain developed in polymer-rich regions is the driving failure cause in the case of 45° off-axis specimen.