论文部分内容阅读
通过对PVC膜材料进行7种应力比下的双轴拉伸试验(比值分别为0∶1、1∶5、1∶2、1∶1、2∶1、5∶1和1∶0),对膜材料在双轴拉伸作用下的拉伸特性进行了研究。在试验过程中施加了3次循环荷载,以使得经过循环作用后的膜材料的性能更接近实际使用的情况。结果表明膜材料具有明显的正交异性和非线性。该文推导了双轴拉伸作用下经纬向应变之间的关系,结合试验所得的变形特性,就经纬向应力比C≤0.5时,经向弹性常数为负这一现象作了分析。根据已有的理论,对膜材料双轴向弹性常数进行了分析,当C=1时,膜材料的经向和纬向同时具有最大的弹性常数。
The biaxial tensile test at 7 kinds of stress ratio (ratio of 0: 1, 1: 5, 1: 2, 1: 1, 2: 1, 5: 1 and 1: 0 respectively) The tensile properties of the film material under biaxial stretching were studied. Three cycles of loading were applied during the test to make the membrane material after cycling more closely behaved in practical use. The results show that the membrane material has obvious orthotropism and nonlinearity. This paper deduces the relationship between the warp and the weft strain under the biaxial tension. Based on the deformation characteristics obtained from the test, the phenomenon that the warp direction elastic constant is negative when the stress ratio in the warp and weft direction is less than or equal to 0.5 is analyzed. According to the existing theory, the biaxial elastic constants of membrane materials are analyzed. When C = 1, the membrane material has the maximum elastic constant in the meridional and latitudinal directions at the same time.