双轴经编织物膜梯形撕裂扩展机制及其拉剪耦合行为  

Trapezoidal tearing propagation mechanisms of biaxial-warp-knitted fabric composites and tensile-shear coupling behaviors involved

作　　者：陈建稳 马俊杰[1] 赵兵[2] 陈务军[2] CHEN Jianwen;MA Junjie;ZHAO Bing;CHEN Wujun(School of Safety Science and Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;Space Structures Research Center,Shanghai Jiao Tong University,Shanghai 200030,China)

机构地区：[1]南京理工大学安全科学与工程学院,南京210094 [2]上海交通大学空间结构研究中心,上海200030

出　　处：《复合材料学报》2023年第12期6922-6933,共12页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金项目(51608270);江苏省基础研究计划(自然科学基金)资助项目(BK20191290);中央高校基本科研业务费专项资金资助(30920021143);中国博士后科学基金资助项目(2017T100371)。

摘　　要：针对经编织物类膜材,考虑纱线方向性及其细观力学结构,进行了系列纱线偏转(梯度15°)及裂缝参数下梯形撕裂试验及数值研究,探讨了撕裂强度及力学行为受参数影响规律,论证了裂纹扩展机制及其涉及的拉剪耦合行为特征。结果表明:裂缝扩展与主纱应力三角区及X形剪应力区的衍变存在显著关联,并据此可界定撕裂历程中各典型阶段。经纬纱间的协同变形及材料的拉剪耦合作用是材料撕裂性能表现出纱线方向依赖性的主要诱因,且随偏角趋于45°两因素均呈现出规律性变化,进而造成裂纹两向杂糅延展及撕裂抗力的“山脊”式变化规律的呈现。所得结论可为相关织物膜材的损伤分析及膜结构安全性评估提供有益参考。Considering the yarn orientation and microscopic structure of the biaxial-warp-knitted fabric,a series of experimental and numerical studies on trapezoidal tearing under off-axis and crack parameters were conducted at first.Then,the influences of parameters on the tearing strength and mechanical properties were investigated.Finally,the crack propagation mechanisms and the characteristics of tensile-shear coupling behavior involved were demonstrated.Results show that there is a significant correlation between crack propagation and the evolution of the main yarn delta zone as well as the X-shaped shear stress region,and the typical stages in the tearing history can be defined.Also,the tensile-shear coupling of the material and the cooperative deformation between warp and weft yarns are the main factors that cause tearing properties to show a dependence on yarn orientation.In addition,both factors vary regularly as the off-axis angle tends to 45°and cause mixed propagation of cracks in both directions and the"ridge"pattern of tearing strength.The conclusions obtained can provide references for damage analysis of related fabric composites and safety assessment of membrane structures.

关 键 词：双轴经编织物膜 拉剪耦合 裂纹扩展 撕裂强度 非线性 

分 类 号：TB332[一般工业技术—材料科学与工程] TS186.1[轻工技术与工程—纺织材料与纺织品设计]