火灾后钢吊柱及其节点受力性能试验研究  

Experimental Study on the Mechanical Properties of Suspended Steel Column and Its Connections after Fire

作　　者：张艳霞[1] 刘栋栋[1] 李磊[2] 李云鹏[1] 

机构地区：[1] 北京建筑大学北京市建筑安全监测工程技术研究中心工程结构与新材料北京高等学校工程研究中心,北京100044 [2] 中国建筑科学研究院建筑防火研究所,北京100013

出　　处：《建筑科学》2014年第3期59-65,106,共8页Building Science

基　　金：国家自然科学基金(51278027);北京市优秀人才项目(2010D005017000009);中青年骨干教师培养计划项目(100603101)

摘　　要：为了对某工程悬挂体系中的钢梁（钢桁架）-钢吊柱及其节点不同程度火灾后的受力性能进行评估,本文制作2组6个钢梁（或钢桁架）-钢吊柱节点缩尺试件,其中每组2个试件按照4条不同的环境升温曲线进行过火试验冷却后对6个试件进行力学试验.试验结果表明：过火试验中试件表面温度低于炉内温度约600℃～ 700℃,说明防火涂料起到了有效的保护作用;钢材表面最高温度为190℃时,屈服荷载、极限荷载和刚度基本没变化;钢材表面平均温度为275℃时,节点和试件屈服荷载提高11.3％,初始刚度下降3.47％;钢材表面最高温度为400℃时,屈服荷载和极限荷载基本没变化,初始刚度下降7.6％;钢材表面平均温度为600℃时,节点和试件屈服荷载下降3％,初始刚度下降14％.SC1系列试件最终在梁柱连接焊缝的热影响区发生脆性断裂破坏,过火后热影响区应变增长速度比钢材应变增长快,说明火灾后焊缝的劣化更严重.In order to evaluate the mechanical properties of suspended steel columns and connections between steel beam（steel truss）-suspended column in a building structure under different post-fire degree, the fire tests of two groups, six reduced scale models of steel beam （steel truss ） -suspended column connections have been taken according to four different environmental temperature curves and tested after refrigeration in this paper. The results show that the temperature in the furnace is about 600℃ - 700℃ lower than the highest environmental temperature, which indicates the protective effect of fire-retardant coatings in fire tests. When the highest temperature of steel surface is 190℃ , the yield load, ultimate load and rigidity are basically invariant; when the highest temperature of steel surface is 275℃ , the yield load of connections and specimens increases 11.3% , but the rigidity declines 3.47% ; when the highest temperature of steel surface is 400℃ , the yield load and ultimate load are almost invariant, the rigidity declines 7.6% ; And when the highest temperature of steel surface reaches 600℃ , the yield load of connections and specimens decreases 3% , meanwhile the rigidity drops 14%. The brittle fracture occurs in heat affected areas of beam-column connection weld specimen series SC1 finally. The strain of heat affected areas grows faster than the steel strain after the fire, which means weld deterioration is more serious after fire hazard.

关 键 词：钢吊柱节点 过火试验 受力性能 试验研究 

分 类 号：TU317[建筑科学—结构工程]