Mechanical properties of GFRP reinforcing bars at high temperatures

Mechanical properties of GFRP reinforcing bars at high temperatures

This paper presents experimental results of tensile strength tests on glass fibre reinforced polymer (GFRP) bars at high temperatures. These results are a part of a comprehensive study on characteristics of GFRP reinforcing bars from different manufacturers. To represent real construction practices, commonly used #5 GFRP reinforcing bars with nominal diameter of 16 mm are studied. The reinforcing bars are selected from three different manufacturers to study the potential differences of various products. Besides conventional steady-state temperature testing, tensile tests are conducted under transient temperature conditions. In transient tests, specimens are loaded before heat exposure. Temperature ranges from 25 to 500 degrees C are considered for the steady-state tests depending on the type of bar, and for the transient temperature tests, bars are loaded to between 25 and 70% of the bar's strength at room temperature. The overall conclusion relating to fire performance of GFRP reinforced concrete members is that the three types of GFRP bars that are tested can retain the expected service stress level of 25% of their original tensile strength up to at least 400 degrees C, and this temperature can be used as the critical temperature in design. (C) 2017 Elsevier Ltd. All rights reserved.

本文介绍了玻璃纤维增强聚合物（GFRP）筋在高温下的抗拉强度试验结果。这些结果是对不同制造商的GFRP增强筋特性进行综合研究的一部分。为了体现实际施工情况，对常用的公称直径为16毫米的#5 GFRP增强筋进行了研究。从三家不同的制造商中选取增强筋，以研究不同产品之间可能存在的差异。除了常规的稳态温度测试外，还在瞬态温度条件下进行了拉伸试验。在瞬态试验中，试件在受热前加载。根据筋的类型，稳态试验考虑的温度范围为25℃至500℃，而在瞬态温度试验中，筋在室温下加载至其强度的25%至70%。关于GFRP钢筋混凝土构件防火性能的总体结论是，所测试的三种GFRP筋至少在400℃时能够保持其原始抗拉强度25%的预期使用应力水平，并且该温度可在设计中用作临界温度。（C）2017爱思唯尔有限公司。保留所有权利。