The performance degradation of fiber-reinforced polymer is often assessed based on the ultimate strength obtained during a destructive test. This method has the advantages of simple operation, clear internal mechanism, and noticeable data variation. However, because fiber-reinforced polymers are composed of high molecular compounds, their properties are influenced by several factors, such as the manufacturing process and composition ratio. Without a unified benchmark, it is difficult to unify destructive test data obtained by different researchers and organizations. In this study, a new test method named SNFT (Same Non-failure FRP Test) is proposed for assessing the durability of fiber-reinforced polymers. SNFT is a testing method in which the same specimen can be repeatedly tested at different aging periods. The rationality of the SNFT method is analyzed using the displacement compatibility between the degraded zone and the undegraded zone. The conversion principle based on the degraded degree between the destructive test and the SNFT method is deduced by calculation. An experimental test was designed to investigate the test conditions and control parameters of the SNFT method. SNFT and synchronous destructive tests on glass fiber–reinforced plastic were carried out under the conditions of wet heat and alkali solution, and the theoretical results were compared and verified with data in the literature. The results show that compared with the traditional durability destructive test method, the SNFT method shows more consistent data and less data fluctuation and incurs a lower test cost. The elastic modulus, adopted as the durability benchmark, can be similar to the test results of traditional destructive test methods and could be transformed based on the transformation relationship proposed in this article. The degradation of fiber-reinforced polymer in different environments is characterized by the variation in elastic modulus measured using the SNFT method. This study provides a theoretical basis for establishing a unified benchmark of durability tests and data and supports the quantitative design of durability.

中文翻译：

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基于弹性模量的纤维增强聚合物耐久性测试方法

纤维增强聚合物的性能退化通常根据破坏性试验期间获得的极限强度进行评估。该方法具有操作简单、内部机制清晰、数据变异明显等优点。然而，由于纤维增强聚合物由高分子化合物组成，其性能受制造工艺和成分比等多种因素影响。没有统一的基准，很难统一不同研究人员和组织获得的破坏性测试数据。在这项研究中，提出了一种名为 SNFT（相同非失效 FRP 测试）的新测试方法来评估纤维增强聚合物的耐久性。SNFT 是一种测试方法，其中相同的试样可以在不同的老化周期重复测试。利用退化区与未退化区的位移相容性分析了SNFT方法的合理性。通过计算推导出破坏性试验与SNFT方法之间基于退化程度的转换原理。设计了一个实验测试来研究SNFT方法的测试条件和控制参数。在湿热和碱溶液条件下对玻璃纤维增​​强塑料进行SNFT和同步破坏性试验，并将理论结果与文献数据进行对比验证。结果表明，与传统的耐久性破坏性测试方法相比，SNFT方法显示出的数据更一致，数据波动更小，测试成本更低。采用弹性模量作为耐久性基准，可以类似于传统破坏性测试方法的测试结果，并且可以根据本文提出的转换关系进行转换。纤维增强聚合物在不同环境中的降解以使用 SNFT 方法测量的弹性模量的变化为特征。本研究为建立统一的耐久性试验和数据基准提供了理论依据，支持了耐久性的量化设计。