Abstract
A simple and rational connection for hybrid structures, which does not require shear connectors or steel reinforcement, has been developed. A material whose tensile strength is high is applied to closed-box structure, members to be connected is then inserted through hole of the closed-box structure, and finally a material which can transfer compression is filled in the closed-box structure. This study discloses that concrete-filled steel box (CFSB), as the developed connection, possesses excellent structural performances and that CFSB can be applied to an actual bridge as abutment after conducting the loading test of specimens with a half scale, execution test of specimen with the real scale, and loading test of the real bridge. Furthermore, concrete constitutive model for compression softening with consideration of confining effects was proposed, and then numerical experimentation by FEM with the proposed constitutive model was conducted to show the effects of inserted length of steel tube (as connected member), ratio of shear force to flexural moment at the beginning of steel tube insertion, steel tube cross-sectional size, steel box size, and concrete strength on the ultimate strength of CFSB under flexural moment.
