CFRP加固混凝土梁不同防火材料保护设计方法  

Fire Design Method for CFRP-Strengthened Reinforced Concrete Beams Protected with Different Coating Materials

作　　者：董坤[1] 胡克旭[1] 王炜浩[1] 彭东平[1] 

机构地区：[1]同济大学结构工程与防灾研究所,上海200092

出　　处：《防灾减灾工程学报》2015年第1期6-10,16,共6页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(50578126)资助

摘　　要：碳纤维增强塑料(CFRP)加固钢筋混凝土结构是目前广泛应用的加固方法之一,但由于CFRP加固构件的耐火性能较差,需进行必要的防火保护。在课题组前期进行的不同防火材料保护的CFRP加固混凝土梁耐火性能试验研究基础上,运用ANSYS有限元分析程序,分别对采取厚型防火涂料、超薄型防火涂料和水泥砂浆作防火保护材料的CFRP加固混凝土梁进行了耐火性能计算分析,结果表明,防火保护层厚度、荷载比、跨高比是影响CFRP加固混凝土梁耐火性能的主要因素,而加固量对耐火性能的影响相对较小。在此基础上,以满足一级耐火极限(≥2.0h)要求的梁跨中挠度限值为标准,根据试验研究及有限元参数分析结果,拟合得到不同防火材料在一级耐火极限要求下的防火保护层厚度计算公式,并给出了3种材料防火保护的合理构造措施,为CFRP加固混凝土梁的防火保护提供了设计方法。Externally bonding carbon fiber reinforced Polymer （CFRP） has been widely used to strengthen concrete structure in recent years. However, fire protection is essential considering the poor fire resistance of CFRP-strengthened members. Based on previous fire tests of CFRP- strengthened reinforced concrete （RC） beams protected with different fireproof materials, this paper focuses on numerical study of fire resistance of CFRP-strengthened RC beams with the pro- tection of thick fire coating, ultra-thin fire coating and cement mortar fire coating. A parametric study is conducted to discover the influences of typical factors on the fire resistance of insulated CFRP-strengthened RC beams. The numerical results show that thickness of fire insulation, load level ratio and span-to-height ratio have greater effect than strengthening ratio. Further, on the basis of experimental studies and numerical analysis, this paper presents a regression formula to calculate the thickness of fire insulation under certain fire prevention requirement and proposes a series of reasonable construction measures with different fire insulations, which provide complete fire design methodology for CFRP-strengthened reinforced concrete beams.

关 键 词：碳纤维加固 钢筋混凝土梁 防火保护设计 

分 类 号：TU352.5[建筑科学—结构工程]