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碳纤维增强复合材料(CFRP)被广泛地应用于钢筋混凝土结构加固。由于碳纤维增强复合材料的高温力学性能较差,外贴CFRP加固体系存在耐火性能不足的缺点。由于锚固性能、黏结性能和延性等方面的优势,嵌入CFRP法(NSM)被越来越广泛地应用于钢筋混凝土梁的加固工程。由于外覆混凝土层和黏结材料的保护,CFRP免于暴露在外部恶劣环境之中,从而具备抵抗火灾的可能。为了了解NSM加固梁在高温下的力学性能,笔者进行了11根碳纤维加固梁和1个对比梁的ISO834标准火灾试验。研究了4个主要因素,即加固方法(嵌入式/外贴技术)、胶黏剂的种类(环氧树脂/氯氧镁水泥)、防火材料(超薄膨胀型涂料/厚型涂层)和防火保温模式(楔入/单面/三面)对梁的高温力学性能的影响。试验结果表明,采用适当的防火保护并选择有效的黏结材料,内嵌CFRP加固钢筋混凝土梁可以达到普通钢筋混凝土梁的耐火水平。该研究为嵌入CFRP加固钢筋混凝土梁的耐火性能设计提供了依据和参考。
Carbon fiber reinforced plastics (CFRP) are widely used in the reinforcement of reinforced concrete structures. Due to the poor mechanical properties of carbon fiber reinforced composites at high temperature, the CFRP reinforced system has the disadvantage of insufficient fire resistance. Due to the advantages of anchoring performance, bonding properties and ductility, embedded CFRP method (NSM) is more and more widely applied to the reinforcement of reinforced concrete beams. Due to the protection of the overburden and the bonding material, CFRP is protected from external harsh environments and thus possesses fire resistance. In order to understand the mechanical properties of NSM reinforced beams under high temperature, the author conducted ISO834 standard fire test of 11 carbon fiber reinforced beams and one contrast beam. Four main factors were investigated, namely reinforcement method (embedded / bonded), adhesive type (epoxy resin / magnesium oxychloride cement), fireproof material (thin intumescent coating / thick coating) Effect of Fire Preservation Mode (Wedge / Single / Three Faces) on High Temperature Mechanical Properties of Beams. The test results show that the CFRP reinforced concrete beams can achieve the fire resistance of common RC beams with suitable fire protection and effective bonding materials. The research provides the basis and reference for the design of refractory performance of CFRP reinforced RC beams.