考虑动力效应的箱型截面钢柱火灾下屈曲温度与临界温度研究  

Buckling and critical temperatures of box-section steel columns in fire considering dynamic effect

作　　者：陈争荣 蒋彬辉 尹中原 王卓琳 王莉萍 CHEN Zhengrong;JIANG Binhui;YIN Zhongyuan;WANG Zhuolin;WANG Liping(National Engineering Research Center of High-Speed Railway Construction Technology,Central South University,Changsha 410075,China;School of Civil Engineering,Central South University,Changsha 410075,China;Shanghai Key Laboratory of Engineering Structure Safety,Shanghai Research Institute of Building Science Co.Ltd.,Shanghai 200032,China)

机构地区：[1]中南大学高速铁路建造技术国家工程研究中心,湖南长沙410075 [2]中南大学土木工程学院,湖南长沙410075 [3]上海市建筑科学研究院有限公司上海市工程结构安全重点实验室,上海200032

出　　处：《中南大学学报（自然科学版）》2024年第2期574-585,共12页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(52378547,51908560);中国中铁股份有限公司科技研究开发计划项目(2021-专项-04-2);上海市优秀技术带头人项目(21XD1434100)。

摘　　要：通过参数分析研究考虑动力效应的箱型截面钢柱火灾下的屈曲温度与临界温度。考虑转动约束刚度比、轴向约束刚度比、荷载比,建立约束钢柱有限元模型,并采用文献中的试验进行验证。研究结果表明,约束钢柱静力分析和显式动力分析的屈曲温度几乎一致,而由静力分析得到的临界温度略小于由显式动力分析得到的临界温度,差别在30℃以内。随着转动约束刚度比的增大,屈曲温度与临界温度均上升,并且转动约束刚度比对临界温度的影响更大。随着轴向约束刚度比和荷载比的增大,约束钢柱的屈曲温度和临界温度均出现明显下降。基于参数分析的结果,在已有文献中关于钢柱屈曲温度和临界温度计算公式的基础上,提出新的屈曲温度和临界温度计算公式,提出的计算公式预测结果与本文有限元模拟结果吻合较好,利用试验数据对提出的屈曲温度和临界温度计算公式的有效性做进一步的验证,对比结果表明提出的计算公式可以很好地预测钢柱的屈曲温度和临界温度。The buckling and critical temperatures of box-section steel columns in fire were studied by parametric analysis.The finite element model of the restrained steel column was validated by test data in literatures considering the rotational restraint stiffness ratio,axial restraint stiffness ratio and load ratio.The results show that the buckling temperatures obtained by the static analysis and explicit dynamic analysis are almost the same,and the critical temperatures obtained by static analysis are slightly lower than those obtained by explicit dynamic analysis,and the difference is within 30℃.The buckling and critical temperatures both increase with the increase of rotational restraint stiffness ratio.Besides,the rotational restraint stiffness ratio has greater influence on the critical temperature than that on the buckling temperature.In addition,with the increase of axial restraint stiffness ratio and load ratio,both the buckling and critical temperatures decrease significantly.Based on the analysis results of the current study and the existing calculation formulas about buckling and critical temperatures in literatures,new calculation formulas for buckling and critical temperatures of steel columns are proposed,respectively.The prediction results of the proposed calculation formulas are in good agreement with the analysis results.The validity of the proposed formulas of buckling and critical temperatures is further verified by test data.The comparison results show that the proposed formulas can well predict the buckling and critical temperatures of steel columns.

关 键 词：约束钢柱 火灾 动力效应 屈曲温度 临界温度 计算公式 

分 类 号：TU391[建筑科学—结构工程]