中文摘要：

对250μm厚乙烯-四氟乙烯（Ethylene-Tetra-Fluoro-Ethylene,ETFE）薄膜进行了单轴循环拉伸试验,通过试验得出ETFE薄膜的应力应变曲线,基于宏观现象和各向同性材料小应变假设,推导了适用于ETFE薄膜单轴循环拉伸第1次加载和卸载的本构方程,编写了采用两步法确定本构方程中参数的程序,利用程序模拟了ETFE薄膜在循环拉伸状态下第1次加载和卸载的应力应变关系.通过与试验得到的应力应变关系对比分析,验证了该本构方程和程序的正确性.提出的ETFE薄膜的本构方程可以较为准确地预测ETFE材料的应力应变关系,为ETFE薄膜结构的分析和计算提供参考.

英文摘要：

Uniaxial cyclic tensile tests on ethylene-tetra-fluro-ethylene（ETFE）foil with a thickness of250μm were conducted.The resulting stress-strain curves were calculated and evaluated thoroughly.Based on the macroscopic phenomena,the small strain of isotropic materials was assumed,and the constitutive equation was derived for ETFE foils applied uniaxial cyclic tensile at the first loading and unloading phase.Using the two-step method,the program was coded for identifying the parameters of the constitutive equation.Moreover,the stress-strain curve of ETFE in the first loading and unloading cycle was simulated.The analysis of the relationship of stress-strain between simulation and experiment proves that the constitutive equation and program are correct.The proposed constitutive equation of ETFE foil can be more accurately in predicting the stress-strain relationship of ETFE foil and provide guidance for analysis of ETFE foil.