Experimental study and finite element analysis on tensile capacity of high-neck flange of steel tube tower

The axial tension and eccentric tension tests of four sets of full-scale Q345 high-neck flange joints with unequal diameter tubes were carried out, and the tensile properties of unequal diameter high-neck flange joints with different strength grades were studied. The results show that the deformation pattern and failure mechanism of each specimen are consistent, and the deformation of the flange joint is concentrated on the steel tube of smaller diameter. The failure of the flange and the butt weld is not visible. The bearing capacity of the specimen is up to 1.5 times of the design value, which shows enough safety. Eccentric load reduces the bearing capacity of the specimen, but the effect is only about 6%. The flange joints with different strength grades works well. The edge of flange neck near welding line is affected by residual stress. It's suggested that the welding line between flange and tube should satisfy first level. Based on the nonlinear finite element analysis, the bearing capacity of the flange is studied. It shows that the results of finite element analysis and experimental study are consistent. © 2018, Editorial Office of Journal of Building Structures. All right reserved.