Warp-loaded mechanical performance of 3D orthogonal layer-to-layer woven composite perforated structures with different apertures

Abstract

Owing to the superior mechanical performance, 3D orthogonal layer-to-layer woven composites (3DOLWC) are being increasingly favored in structural design. Its perforated structure (called 3DOLWC-PS) is a typical component in engineering, but its mechanical behavior is not clear, especially with different apertures, which enormously limits the application of 3DOLWC. In this paper, we discuss the mechanism of meso-randomness through the characterization of 3DOLWC, and establish its random unit cell model. On this basis, a macro-meso finite element simulation model of 3DOLWC-PS is built. Subsequently, combined with a developed continuous damage mechanics model, 3DOLWC-PS is simulated and verified by experiments. The results demonstrate that the established macro-meso simulation model can precisely predict the mechanical properties of 3DOLWC-PS and effectively explore its failure behavior. Furthermore, with the aperture increases, the strength of 3DOLWC-PS decreases linearly, but its stiffness is almost unchanged. It is worth mentioning that the notched stress concentration effect only affect the initial damage, but has little effect on the subsequent damage propagation process. This work provides the theoretical guidance and points out the design direction for the application of 3DOLWC-PS, and has crucial engineering significance.