A comprehensive study on enhancing the fire resistance of Glass Fiber-Reinforced Polymer (GFRP) reinforced concrete columns and slabs

本项目旨在对火灾中的玻璃纤维增强聚合物（GFRP）增强混凝土构件，即柱和板进行全面研究。本研究将有三个主要的实验阶段：(1)在环境室中对MST棒进行标准拉拔试验；(2)对末端涂有膨胀涂层的gfrp -钢筋混凝土板进行中期和全尺寸标准防火试验；(3)一根全尺寸的全玻璃钢钢筋柱将在北美首次在标准火力下进行测试。迄今为止，FRP钢筋在高温下粘结强度的损失和退化已被确定为FRP钢筋混凝土（RC）构件防火性能不如钢筋混凝土（RC）构件的主要原因。试验结果表明，如果FRP筋两端的温度保持在玻璃化转变温度以下，则FRP RC构件的粘结破坏将显著改善。为了实现这一目标，建议保护FRP RC构件的锚固区免受直接火灾的影响，以延迟温度在锚固区嵌入FRP钢筋的传播。近年来，超薄膨胀涂层在混凝土中的应用已显示出良好的效果。薄膜膨胀涂层极大地保护结构元件免受火灾中可能发生的极端温度的影响。膨胀涂层是一种易于应用且具有成本效益的传统被动防火层替代品。前面提到的测试将用于检查GFRP增强混凝土柱的性能，以及GFRP箍筋和GFRP纵筋在火灾中的性能。通过这次合作，MST Rebar将对GFRP RC柱的耐火性能充满信心，并提供切实可行的措施来提高GFRP RC板的耐火性能。加拿大规范，如CSA-S806，是专门为推广GFRP混凝土结构而制定的。这项研究的结果将为加拿大制定CSA-S806的规定提供知识。

This project aims to provide a holistic investigation of Glass fibre reinforced polymer (GFRP) reinforced concrete members in fire, namely columns and slabs. This research will have three main experimental phases: (1) standard pullout tests on MST bars in an environmental chamber; (2) intermediate and full-scale standard fire tests will be conducted on GFRP-reinforced concrete slabs with intumescent coating at the ends of the slabs; and (3) a full-scale column entirely reinforced with GFRP bars will be tested under standard fire for the first time in North America. To date, the loss and degradation of bond strength of FRP reinforcing bars at high temperatures has been identified as the main cause of the inferior fire performance of FRP-reinforced concrete (RC) elements compared to steel RC ones. The test results have revealed that if temperatures at both ends of an FRP bar remain below its glass transition temperature the bond failure of the FRP RC member will significantly improve. To achieve this, the anchorage zones in FRP RC members are recommended to be protected from direct fire exposures to delay the temperature propagation into the embedded FRP reinforcing bars at the anchorage zones. Recently, the application of intumescent coatings with very thin layers has shown promising results with delayed temperature propagation into the concrete. The thin-film intumescent coatings greatly protect structural elements against severe temperatures that can occur in fires. The intumescent coatings are an easy-to-apply and cost-effective alternative to conventional passive fire protection layers. The previously mentioned tests will be used to examine the performance of GFRP reinforced concrete columns, as well as the behaviour of GFRP stirrups and GFRP longitudinal bars during a fire. Through this partnership, MST Rebar will be confident in the fire resistance of GFRP RC columns and offer practical measures to enhance the fire resistance of GFRP RC slabs. Canadian codes, such as CSA-S806, are specifically developed to promote GFRP RC structures. The outcome of this research will provide knowledge in developing provisions for CSA-S806 in Canada.