This paper selects polyvinyl chloride- (PVC-) coated fabrics to study its off-axial tensile behaviors under different off-axis angles including 0°, 15°, 30°, 45°, 60°, 75°, and 90°. In the experiment, dumbbell-shaped and strip-shaped specimens are analyzed for shape effect. The variations in the strain distribution are studied by using digital image correlation (DIC) noncontact full-field measurement system. The shape and off-axis angle of specimens are analyzed to predict the influences of shape effect. The results show that the longitudinal strain and shear strain of the coated fabrics are obviously symmetrical to the off-axis direction. The shear strain distribution of the two kinds is basically the same, but the longitudinal strain fields are different. The off-axis tensile properties of the material are obviously anisotropic and nonlinear. The tensile testing curve of the specimens mainly consists of three stages: initial linear stage, deformation strengthening stage, and stress strengthening stage. At 0°, the tensile strength is the largest and the elongation at break is the smallest. In contrast, at 45°, the elongation at break is the highest and the tensile strength was the smallest. The properties under the other off-axis angles were between these two extremes.

中文翻译：

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轴心张力作用下PVC涂层织物力学性能的形状效应分析

本文选择聚氯乙烯（PVC-）涂层的织物来研究其在不同偏轴角（包括0°，15°，30°，45°，60°，75°和90°）下的离轴拉伸性能。在实验中，分析了哑铃形和条形样本的形状效果。通过使用数字图像相关（DIC）非接触式全场测量系统研究了应变分布的变化。分析样品的形状和偏轴角，以预测形状效应的影响。结果表明，涂​​层织物的纵向应变和剪切应变与离轴方向明显对称。两种剪切应变分布基本相同，但纵向应变场不同。材料的离轴拉伸性能明显是各向异性和非线性的。试样的拉伸试验曲线主要包括三个阶段：初始线性阶段，变形强化阶段和应力强化阶段。在0°时，抗拉强度最大，断裂伸长率最小。相反，在45°时，断裂伸长率最高而抗拉强度最小。其他离轴角下的特性介于这两个极端之间。