In recent years, non-welded building hardware that can be installed by bolt assembly is used. However, there is a need for a method to compensate for the occurrence of buckling at the bolted portion at the time of construction. The purpose of this study is to evaluate the behavior of joints between steel square pipe and fastener.

This paper describes the structural performance of coupling beam with diagonal steel tube for reinforcement detail simplification of RC coupling beam. Two coupling beams were made and tested to compare the structural performance of coupling beam with diagonal steel bar and that with diagonal steel tube.