不锈钢焊接箱形截面压弯构件弯曲屈曲试验研究

为了研究不锈钢焊接箱形截面压弯构件的弯曲屈曲，该文对5根奥氏体型和5根双相型不锈钢焊接箱形截面柱进行了偏心受压试验，试件长细比在55~85，荷载偏心距分别设计为50 mm、60 mm、70 mm，并且在试验前对试件的初始弯曲和荷载初偏心进行了测量。根据试验结果对构件静力承载性能进行了分析，并将试验结果分别与CECS 410:2015《不锈钢结构技术规程》和欧洲规范EN 1993-1-4中不锈钢压弯构件承载力的计算值进行了对比。结果表明:所有构件均发生平面内的整体弯曲失稳，且整体失稳前没有发现明显的局部板件屈曲；构件承载力随着偏心距、长细比的增大而降低；对于双相型不锈钢压弯构件，依据CECS 410:2015和EN 1993-1-4的计算值较试验结果均偏于安全；对于奥氏体型不锈钢压弯构件，依据EN 1993-1-4的计算值较试验结果均偏于安全，依据CECS 410:2015的个别试件计算结果略低于试验结果，但整体偏于安全。

EXPERIMENTAL RESEARCH ON FLEXURAL BUCKLING OF STAINLESS STEEL WELDED BOX-SECTION BEAM-COLUMNS

In order to investigate flexural buckling of stainless steel welded box-section beam-columns, 5 austenitic and 5 duplex stainless steel welded box-section columns are loaded eccentrically, with values of slenderness varying from 55 to 85. The design loading eccentricities are 50 mm, 60 mm and 70 mm, and the initial bending and loading eccentricities are measured before the test. The static loading capacity of the components is analyzed based on the test results, which are compared with the predictions based on current specifications CECS 410:2015 and EN 1993-1-4. The results indicate that all members failed in the form of overall flexural buckling without obvious local buckling. The bearing capacity decreases with increase of slenderness and loading eccentricities. For the duplex stainless steel welded beam-columns, both EN 1993-1-4 and CECS 410:2015 provide conservative prediction on the loading capacity. Moreover, as for the austenitic stainless steel welded beam-columns, EN 1993-1-4 also provides conservative prediction on the loading capacity. Although the test results of individual specimens are slightly lower than the calculation results of CECS 410:2015, most prove to be safe generally.