Experimental Research On Concrete Structure With Specially-shaped Columns Joints By X-Shaped Reinforcement

The reinforced concrete (RC) frame structure with specially-shaped columns has been widely applied in China because of its good architectural functions in recent years. In order to developing and improving specially-shaped columns of RC, Domestic scholars have done many experiment research and theory analysis on components, such as beam-column joints and RC frames with specially-shaped columns. The results show that: special sections of the columns in this structure have made the joints of beam-columns weaker than those of the rectangular column, which limit the building height and the scope of application of specially-shaped column structure. How to enhance the seismic behavior of the weak part like the beam-column joints, so as to improving the building height and expanding the scope of application is urgent.In this paper, X-shaped reinforcement has been used to reinforce the joints of specially-shaped columns of RC .Based on the contrast experiment that about the frame with specially-shaped columns reinforced by X-shaped reinforcement in the joints, Verified that X-shaped reinforcement reinforced concrete in joints'weak position combination is feasible.In this paper, low-cyclic reversed tests have been conducted on joints with X-shaped reinforcement and general joints of specially-shaped columns of RC. Compare the seismic behavior result of the two exterior joints and the two middle joints. The results show that: the setting of X-shaped reinforcement in the joints region could improve the damage characteristics of the joints with specially-shaped columns significant, enhance the cracking load of the joint core zone, reduce the cumulative damage and advance the shear capacity.In this paper, the shear mechanism of specially-shaped columns is studied according to the rectangular column joint, the bearing shear capacity of the joints with specially-shaped columns is studied.