摘要
为了解决现行设计标准中钢梁弯扭屈曲极限弯矩计算方法在适用范围和计算精度上存在的问题,提出了基于理想轴压构件整体屈曲临界荷载的理想钢梁弹性弯扭屈曲临界弯矩计算式,并进一步提出了基于轴压构件稳定系数的简支钢梁弯扭屈曲极限弯矩计算方法。采用124个热轧H型钢梁试件、80个焊接梁试件、2个薄腹梁试件共计206个钢梁试件弯扭屈曲极限弯矩的试验结果,检验了方法的适用范围及计算精度,并与GB 50017—2017《钢结构设计标准》中的方法进行了对比。研究表明:对于206个钢梁试件,基于轴压构件稳定系数的计算方法较GB 50017—2017方法的适用范围更广,且与已有文献的计算精度相当;对于7个单轴对称工字形截面焊接高强钢梁试件,基于轴压构件稳定系数的计算方法略偏安全且精度高,而GB 50017—2017中的方法偏不安全;对于44个荷载工况不包含在GB 50017—2017中的钢梁试件,建议方法所得极限弯矩计算值与实测值之比的均值、标准差分别为0.908、0.125,精度较高且偏于安全。
In order to deal with the existing problems for the application range and accuracy of the design approach for flexural-torsional buckling(FTB)ultimate moment in current design standard,formula of elastic critical moment for steel beams governed by FTB was proposed on the basis of elastic critical loads of columns subjected to global buckling.Furthermore,the calculated method for FTB ultimate moment was also proposed on the basis of stability factor of columns.The FTB experimental results of 124 rolled,80 welded and two girder I-section beams(a total number of 206 specimens)were employed to evaluate the application range and accuracy of the proposed method.The results were compared with the design approach in GB 50017—2017‘Standard for design of steel structures’.The results show that,for the considered 206 specimens,the proposed method is of wider application range than GB 50017—2017 and comparative accuracy compared with the results in the existing literature.For the seven singly symmetric I-sections specimens,the proposed method is accurate and slightly safe,but the design approach in GB 50017—2017 is unsafe.For the 44 singly I-section specimens under load cases which are not included in GB 50017—2017,the mean and standard deviation of ratio of the results determined by the proposed method to experimental results,are 0.908 and 0.125 respectively,indicating the proposed method is accurate and safe.
作者
刘占科
宋诗羽
马张永
周绪红
LIU Zhanke;SONG Shiyu;MA Zhangyong;ZHOU Xuhong(Key Laboratory of Mechanics on Disaster and Environment in Western China,the Ministry of Education of China,Lanzhou University,Lanzhou 730000,China;College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China;Gansu Science and Technology Construction Group Co.,Ltd,Lanzhou 730300,China;School of Civil Engineering,Chongqing University,Chongqing 400044,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2024年第4期166-176,共11页
Journal of Building Structures
基金
国家自然科学基金项目(52278184)
兰州大学中央高校基本科研业务费专项资金(lzujbky-2021-kb03)。
关键词
简支钢梁
弯扭屈曲
极限弯矩
临界弯矩
轴压构件稳定系数
simply supported steel beam
flexural-torsional buckling
critical moment
ultimate moment
stability factor of column
