Q345冷成型钢高温力学性能试验制度参数的影响研究  

Influence of test procedure parameters on high-temperature material properties of Q345 cold-formed steel

作　　者：陈伟[1,2] 叶继红 金磊[1,2] 姜健 刘琨 秦雅菲 CHEN Wei;YE Jihong;JIN Lei;JIANG Jian;LIU Kun;QIN Yafei(Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Engineering,China University of Mining&Technology,Xuzhou 221116,China;Xuzhou Key Laboratory for Fire Safety of Engineering Structures,China University of Mining&Technology,Xuzhou 221116,China;Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China)

机构地区：[1]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 [2]中国矿业大学工程结构火安全实验室,江苏徐州221116 [3]宝山钢铁股份有限公司,上海201900

出　　处：《建筑结构学报》2022年第9期151-159,共9页Journal of Building Structures

基　　金：江苏省自然科学基金面上项目(BK20201347);徐州市科技计划项目(KC20175)。

摘　　要：钢材的火灾全过程高温本构是开展冷成型钢结构抗火研究的重要输入数据。为此,开展国内常用Q345冷成型钢高温力学性能试验研究,定量考察峰值温度保温时间、降温速率、温度历程以及稳态与瞬态试验方法等试验制度参数对其力学性能的影响,结果表明:高温稳态试验中,峰值温度保温时间和降温速率对钢材高温力学性能影响不明显,相对百分偏差均介于-10%~10%之间;若温度历程中各次升温过程峰值温度中的最高温度和拉伸温度均相同,则钢材在多次升降温过程下的高温力学性能与其在一次升降温过程降温段的高温材性相互接近;高温瞬态试验中,温度历程对钢材高温试验应变影响显著;相同拉伸温度下,升温与降温段的应变相对偏差最高可达12904%;稳态与瞬态试验方法对考虑温度历程的冷成型钢高温应变影响亦非常明显,试验参数范围内,相同拉伸温度下应变相对百分偏差最大可达14851%。总之,Q345冷成型钢的火灾全过程高温本构需考虑温度历程中各次升温过程峰值温度中的最高温度和拉伸温度的影响,且稳态与瞬态试验方法所构建的高温本构模型并不等效。The high-temperature constitutive model of steel during the whole fire process is an important input parameter for the fire resistance study of cold-formed steel(CFS)structures.An experimental investigation on the high-temperature mechanical properties of Q345 CFS commonly used in China was carried out.The effects of four types of test procedure parameters on the mechanical properties were quantitatively investigated,including peak temperature holding time,cooling rate,temperature history,and steady-state and transient test methods.The results show that for the high-temperature steady-state tests,the peak temperature holding time and cooling rate have little effect on the high-temperature mechanical properties of Q345 CFS,and the relative percentage deviations are within-10%-10%.Meanwhile,under the same tensile temperature and the highest temperature of the peak temperatures of each heating and cooling stage in the temperature history,the high-temperature mechanical properties of Q345 CFS under multiple heating and cooling stages are close to those of the cooling stage section of one heating and cooling stages.For the high-temperature transient tests,the effect of the temperature history on the high-temperature strain of Q345 CFS is significant.In these experiments,under the same tensile temperature,the relative percentage deviation between the strain of the heating and cooling stages can reach up to 12904%.The steady-state and transient test methods also have significant effects on the high-temperature strain of Q345 CFS.Within the experimental parameters,the relative percentage deviation between the strain of the steady-state and transient test methods can reach up to 14851%at the same tensile temperature.In conclusion,the high-temperature constitutive model of Q345 CFS during the whole process of fire needs to consider the influence of the highest temperature and tensile temperature in the peak temperatures of each heating and cooling stage in the temperature history.In addition,the high-temperature constituti

关 键 词：冷成型钢 温度历程 试验制度参数 升温和降温阶段 稳态和瞬态试验 

分 类 号：TU392.103[建筑科学—结构工程]