聚四氟乙烯膜材黏弹性本构关系  

Viscoelastic constitutive relations of polytetrafluoroethylene coated fabrics

作　　者：张营营[1,2] 许珊珊[1,2] 徐俊豪 张其林[3] 

机构地区：[1]中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室,江苏徐州221116 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [3]同济大学土木工程学院,上海200092

出　　处：《建筑结构学报》2016年第6期245-252,共8页Journal of Building Structures

基　　金：国家自然科学基金项目(51308532;90815003);中国博士后科学基金项目(2013M541756)

摘　　要：为研究聚四氟乙烯(PTFE)膜材的黏弹性本构关系,进行了蠕变试验和应力松弛试验,考虑了初始拉伸速率、初始应力对于PTFE膜材黏弹性性能的影响,并采用常用的黏弹性本构关系模型对试验数据进行了拟合,分析了应力松弛和蠕变之间的相互转化关系。研究表明:PTFE膜材具有明显的黏弹性性能,在设计中应予以考虑;初始应力对膜材料的黏弹性性能影响明显,初始应力越大,黏弹性越明显,而初始拉伸速率的影响相对较小;五元件广义Kelvin模型、Burgers模型、分指数模型能够较好地预测膜材料的蠕变黏弹性性能,而基于金属材料的蠕变-应力松弛转化关系不能直接用于分析PTFE膜材的黏弹性转化关系。In order to study the viscoelastic constitutive relations of PTFE coated fabrics, the creep tests and stress relaxation tests of PTFE （polytetrafluoroethylene） coated fabric were carried out, in which the effects of initial stress and initial tensile rate are considered. Several viscoelastic constitutive relations are used to fit the experiment data and the relationship between creep and stress-relaxation is discussed. Results show that FIFE coated fabrics are typically viscoelastic, which should be considered in the design and analysis. The effect of initial stress level on the material viscoelasticity is significant. With initial stress increasing, the material viscoelasticity becomes more obvious. The effect of initial tensile rate on the material viscoelasticity is not significant. The five-component generalized Kelvin model, Burgers model and fractional exponential model can be used to simulate the creep behaviors of VFFE coated fabrics, which is related to the components of constitutive relations. The transformation relationship between creep and stress relaxations based on the metals can not be directly used in the analysis of PTFE coated fabrics.

关 键 词：聚四氟乙烯膜材 蠕变试验 松弛试验 黏弹性本构关系 应力松弛 蠕变 

分 类 号：TU383[建筑科学—结构工程] TU317.1