摘要: |
对聚四氟乙烯(PTFE)膜材进行了9种温度(-20,-10,0,10,23,40,50,60,70℃)下的单轴单调和循环拉伸试验,得到了膜材力学参数的变化规律.结果表明:随着温度的增加,PTFE膜材的抗拉强度逐渐减小,而断裂延伸率和弹性模量逐渐增大;随着循环次数的增加,PTFE膜材滞回曲线趋于稳定,残余应变趋于常数.在试验研究的基础上,提出了PTFE膜材强度的温度影响系数,为PTFE膜材强度设计分项系数的取值提供了依据. |
关键词: 聚四氟乙烯(PTFE)膜材 温度 循环荷载 高温折减系数 |
DOI:10.3969/j.issn.1007 9629.2012.04.008 |
分类号: |
基金项目:国家自然科学基金资助项目(90815003);国家科技支撑计划项目世博科技专项(2009BAK43B06);光华同济土木学院基金资助项目 |
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Effects of Temperature on Mechanical Properties of PTFE Coated Fabrics |
ZHANG Ying ying1, ZHANG Qi lin2, ZHOU Chuan zhi2
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1.Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering, China University of Mining & Technology, Xuzhou 221116, China;2.College of Civil Engineering, Tongji University, Shanghai 200092, China
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Abstract: |
Uniaxial tensile tests on poly tetra fluoro ethylene(PTFE) coated fabric were carried out under monotonic and cyclic loading, in which nine environment temperatures were considered including -20, -10, 0, 10, 23, 40, 50, 60 and 70℃. The variation trends of membrane mechanical properties were obtained. The test results show that the membrane tensile strength will decrease, and the breaking strain and the elastic modulus will increase with the increase of the environment temperatures. The hysteresis curves of the membrane material will tend to stable and the unloaded residual strain will tend to a constant with the increase of the loading cycles. On the basis of the test results the temperature influence factors of the membrane strength are proposed, which can be taken in the study of the partial coefficients of membrane strength design value. |
Key words: poly tetra fluoro ethylene(PTFE) coated fabric temperature cyclic loading high temperature reduction factor |