考虑保温构造的足尺冷成型钢复合墙体承重抗火试验研究  

Investigation on fire experiments of full-scale load-bearing cold-formed steel walls with insulation configuration

作　　者：陈伟[1,2] 刘康[1,2] 叶继红 尹亮 姜健 秦雅菲 CHEN Wei;LIU Kang;YE Jihong;YIN Liang;JIANG Jian;QIN Yafei(Xuzhou Key Laboratory for Fire Safety of Engineering Structures,China University of Mining&Technology,Xuzhou 221116,China;Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering,China University of Mining&Technology,Xuzhou 221116,China;Fire Code Research Division,Tianjin Fire Science and Technology Research Institute of the Ministry of Emergency Management,Tianjin,300381,China;Baoshan Iron&Steel Co.,Ltd,Shanghai 201900,China)

机构地区：[1]中国矿业大学徐州市工程结构火安全重点实验室,江苏徐州221116 [2]中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室,江苏徐州221116 [3]应急管理部天津消防研究所消防规范研究室,天津300381 [4]宝山钢铁股份有限公司,上海201900

出　　处：《建筑结构学报》2023年第10期146-155,共10页Journal of Building Structures

基　　金：江苏省自然科学基金面上项目(BK20201347);徐州市重点研发计划(KC20175)。

摘　　要：为解决普通轻钢结构抗火性能差、推广应用受限等问题,设计制作18片足尺冷成型钢复合墙体,开展墙体常温轴压与承重抗火试验研究,考察覆板构造、高吸水树脂(SAP)保温材料、热膨胀荷载等因素对墙体耐火性能的影响,提出相关抗火设计建议。结果表明:墙体因初始荷载比率、覆面板材的差异呈现两类受火破坏模式,即墙柱端部全截面压屈破坏和墙柱热翼缘局部屈曲进而发生墙柱向背火侧弯曲破坏;考虑膨胀约束后的墙柱轴压承载力最大提高幅度可达162%,明显加快高温承载力的退化速率,其耐火极限减小,建议复合墙体作为非承重隔墙使用时,其墙体顶端与相应楼盖接触面之间应留有至少10 mm的轴向膨胀间隙;墙柱受火失效临界温度不仅与初始荷载比率、墙体覆板与填充层构造密切相关,墙柱热翼缘宽厚比和温度膨胀约束等因素影响亦不可忽略,建议将墙柱受火失效临界温度与墙柱受火温升简化计算方法相结合,实现复合墙体高效抗火设计;通过在墙体墙柱中加入SAP保温材料,可进一步提升墙体抗火性能;当有耐火需求较高时,推荐采用蒸压加气混凝土板和波特板覆板的外置保温单C89形截面墙柱构造,其在中等初始荷载比率0.55条件下,可以达到我国GB 50016—2014《建筑设计防火规范》中多高层建筑结构承重墙一级耐火等级的耐火极限(不低于3 h)要求。To address the fire resistance issue in the widespread application of multi-story cold-formed steel(CFS)structures in China,18 full-scale CFS wall specimens were designed.Axial compression tests at ambient temperature and load-bearing fire experiments were carried out on the walls,the factors including sheathing construction,superabsorbent polymers(SAP)insulation material,thermal expansion load were studied to investigate their influence on the fire performance of walls,and corresponding suggestions on fire-resistant design were proposed.The results show that:the CFS walls display two types of failure modes due to differences of initial load ratios and sheathing boards,namely,the local buckling of the whole stud section at the ends of wall studs and the local buckling of the hot flange(HF)which result in flexural failure of the wall studs towards the ambient side.Considering the effect of expansion constraints,the maximum increase in the axial compressive capacity of wall studs can reach up to 162%,which significantly accelerates the loss of their high-temperature bearing capacity.It is recommended that when adopting CFS walls as non-load-bearing partitions,there should be at least 10 mm axial expansion gap between the top of the wall and the corresponding floor interface.The failure critical temperature of wall studs is not only closely related to the initial load ratios,sheathing boards and cavity insulation construction,but also is affected by other factors including the width-thickness ratios of the HF and thermal expansion constraints.It is recommended to combine the simplified calculation methods for the failure critical temperature of wall studs and the temperature rise of wall studs in fire,in order to achieve efficient fire-resistant design of CFS walls.The fire resistance of the wall can be further improved by adding SAP insulation material to the wall studs.When the walls have high fire resistance rating requirements,it is recommended to use autoclaved lightweight concrete board and calcium-silicate bo

关 键 词：冷成型钢复合墙体 覆面板材 SAP保温材料 足尺抗火试验 热膨胀荷载 

分 类 号：TU392.1[建筑科学—结构工程] TU317.1