FRP加强R/C梁防火性能调查研究

对纤维加强聚合物(FRP)材料加强钢筋混凝土梁在火灾中的防火性能进行了研究。试验结果显示,防火材料能够帮助构件达到标准防火性能,同时对不断增长的FRP应用也很重要。介绍了不同文献对FRP在高温下的性能所做的研究以及目前标准对建筑构件的耐火极限要求。对两个大型试验进行了介绍。试验材料为混凝土梁构件,外部用FRP板加强,并且三分之二用专利耐火隔热材料保护。给出了试验结果,并重点强调了曝火状态下所测得的构件温度。试验数据验证了热传导数值模型,该模型可用于预测加强并绝缘钢筋混凝土梁构件内的温度。试验结果和模型数据显示,正确设计和进行绝缘保护的FRP加强梁构件耐火极限能够达到4h或者以上。

An investigation on fire performance of FRP-strengthened R/C beams

As the use of Fibre-Reinforced Polymer(FRP)materials continues to expand into the structural repair market,concerns over the performance of these materials in fire conditions are now at the forefront of research.While externally bonded FRP sheets have been shown to successfully enhance the flexural and shear capacity of bridges and other structures,their application in interior spaces,where fire is a significant concern,remains questionable in light of these materials' comparatively poor resistance to elevated temperatures.This paper presents the results of an ongoing study to document the performance of FRP-strengthened reinforced concrete beam-slabs exposed to fire.With such experimental results,fireproofing materials have the potential to earn standard performance ratings,which are essential to the design engineer and necessary for the continued increase of FRP applications worldwide.A brief synopsis of existing literature related to FRP behaviour at high temperature is provided,in addition to a review of the current fire endurance criteria for structural members.Two large-scale concrete beam-slab assemblies were strengthened with FRP sheets and protected with a two-part patented fire insulation system.The results of fire tests performed on these specimens are presented herein,with emphasis placed on the temperatures measured in the specimens during fire exposure.The data obtained from the tests served to validate a numerical heat transfer model,which predicts the temperature within a strengthened and insulated reinforced concrete beam-slab assembly.Test results and model data indicate that appropriately designed and insulated FRP-strengthened beam-slab assemblies can achieve fire endurances of four hours or more.