Evaluation of local rotational stiffness and strength of beam-to-column connection reinforced by increasing column thickness

The strength and local rotational stiffness of the beam-to-column connection reinforced by increasing column thickness without any diaphragms are presented. The column thickness at the beam-to-column connection area is increased partially by the induction heating process. The structural behaviors of the beam-to-column connection of this type are investigated experimentally and compared with those of the connection with inner diaphragms by the cyclic reversal loading tests of the beam-and-column subassemblage specimens. Also, the elasto-plastic behaviors of the beam-and-column subassemblages and each element are analyzed by the finite clement analysis. The local full plastic and ultimate strength of the beam-to-column connection is evaluated by the yield line theory taking account of the area of the increasing column thickness