关键词: 双轴经编膜材, 刺破性能, 方锥刺具, 片状刺具, 入刺角度, 复合材料

Abstract: Stabbing damage is one of the main failure types for warp-knitted fabric membranes during their serving life. And the stabbing mechanical properties of fabric membranes are extremely important for the safety of membrane structures. The stabbing performances of biaxial warp-knitted fabric membranes (PVDF 8028) were studied through numerical method. The numerical model of stabbing considering the micro structure of yarns and matrix is established by ABAQUS software. By introducing the square cone punch and sheet punch, the morphological characteristics of PVDF 8028 under different punches were analyzed on mesoscale, and the effects of different stabbing angles were systematically investigated. The FEM models were validated from the good agreement between the FEM results and the theoretical results. The results show that, for the square cone punch, the stabbing strength of the membrane material decreases as the horizontal stabbing angle of the square cone punch increases, and the stabbing strength reduction reaches 39.39% when the horizontal stabbing angle grows from 0° to 90°. In terms of the sheet punch, with the increase of the stabbing angle, the stabbing strength shows a tendency that it increases at first and then decreases, and the peak stabbing force-stabbing angle curve shows an inverted "V" shaped characteristic as the stabbing angle increases. The conclusions obtained could provide useful references for damage assessment and safety analysis of membrane structures.

Key words: biaxial warp-knitted fabric membranes, stabbing performance, squarecone punch, sheet punch, stabbing angle, composites