Static and fatigue failure of embedded optical fiber in smart structure

Abstract

Static and fatigue behavior of optical fiber embedded in composite laminate is studied. Comparing the failure strain of cured and uncured optical fibers indicated that strength degradation caused by thermal treatment during the composite laminate curing cycle is serious. The strength of optical fibers embedded within the composite laminate was increased slightly compared to the single fiber strength. Effects of transverse matrix cracks on the failure of optical fiber embedded in transverse ply of cross ply laminate are assessed by the combination of the weakest link theory and the shear lag analysis. Through fatigue experiment of optical fiber embedded composite laminates, it is found that the fatigue life of optical fiber embedded in cross ply laminate is dependent on the fatigue behavior of transverse matrix crack, while the decrease in fatigue life of optical fiber embedded in unidirectional laminate with increasing maximum applied stress is relatively small.