Calculation method of flexural-torsional buckling ultimate moment for simply supported steel beams based on stability factor of columns
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.
simply supported steel beamflexural-torsional bucklingcritical momentultimate momentstability factor of column
国家科技期刊平台
NSTL
万方数据
维普
