Jamilus Research Center, Faculty of Civil Engineering and Built Environment, Universiti Tun Hussein Onn Malaysia, Parit Raja, Johor, Malaysia.
Office of Education in Sana'a, Sana'a, Yemen.
PLoS One. 2020 Feb 3;15(2):e0227895. doi: 10.1371/journal.pone.0227895. eCollection 2020.
Skin crack defects can develop in sandwich honeycomb composite structures during service life due to static and impact loads. In this study, the fracture behavior of sandwich honeycomb composite (SHC) beams containing crack at the skin was investigated experimentally and numerically under four-point loading. Three different arrangements of unidirectional (UD) carbon fiber composite and the triaxially woven (TW) fabric were considered for the skins. The presence of a 10 mm crack at mid-span of the top skin, mid-span of the bottom skin, and mid-way between load and support of the top skin, respectively, were considered. Failure load equations of the load initiating the skin crack extension were analytically derived and then numerically developed using the J-integral approach. The crack extension failure mode dominated all cracked specimens except those with low-stiffness skin which were controlled by the compressive skin debonding and core shear failures.
由于静载和动载的影响，在使用过程中，夹层蜂窝复合材料结构可能会出现表皮裂纹缺陷。本研究采用四点加载的方式，对含表皮裂纹的夹层蜂窝复合材料梁进行了实验和数值研究。分别考虑了三种不同排列的单向（UD）碳纤维复合材料和三轴向编织（TW）织物作为表皮。在顶层和底层表皮的跨中，以及在顶层表皮的载荷和支撑之间的中间位置，分别考虑了 10mm 的裂纹。通过分析推导了起始表皮裂纹扩展的载荷失效方程，然后使用 J 积分方法进行了数值开发。除了那些由压缩表皮脱粘和芯体剪切失效控制的低刚度表皮的试件外，所有出现裂纹的试件均以裂纹扩展失效模式为主。
