Experimental Study On Seismic Behavior Of Imitated Ancient Building Connections Between Concrete Filled Square Steel Tube Columns And Reinforced Concrete Circular Columns

Chinese ancient buildings are an important part of the resplendent Chinese civilization. Few ancient buildings are retained because of war, earthquake and natural reason. For showing the long cultural deposits of Chinese nation, imitated ancient buildings are constructed increasingly with the combining of ancient architectural image and modern structure. For the structural loading features, there is some difference between imitated ancient buildings and ancient buildings, modern buildings.There is no proprietary architectural design code in the structure design of imitated ancient buildings, and current codes aren’t completely applicable.For column connection is an important part of structure, this paper focuses on seismic behavior of imitated ancient building connections between concrete filled rectangular steel tube columns and reinforced concrete circular columns. According to the experimental study on 4 imitated ancient building connections between concrete filled rectangular steel tube column(CFST) and reinforced concrete circular column(RC) under low cyclic reversed loading, the loading process and failure mode under different axial compression ratio were obtained. Deformation features, yielding mechanism, failure mode were analyzed. Seismic behavior indexes such as hysteretic behavior, displacement ductility, energy dissipation capacity, stiffness degradation,strength degradation were analyzed.The study results indicate that the failure mode of the CFST-RC column connections of imitated ancient buildings is mainly flexural failure, and accompanied with shear phenomenon. Plastic hinges with some rotation capacity appear at the rootof CFST columns and RC columns. Column connections have good ductility,hysteretic behavior, energy dissipation capacity and later bearing capacity, and their seismic behavior is good. The axial compression ratio has control effect on the yielding mechanism of upper columns and lower columns. The yielding mechanism has significant effect on ductility and energy dissipation capacity of specimens. According to the experimental results and deformation features, the formula for lateral stiffness is put forward.The static elasto-plastic analysis on CFST-RC column connections of imitated ancient buildings was carried out by using ABAQUS finite element software. The goodness of fit between calculated results and experimental results is well. The effectiveness of model is verified. Furthermore, the parameter analysis on CFST-RC column connections was carried out. The influence law of CFST-RC column connections is obtained under different yield strength of steel tube, concrete strength,reinforcement ratio, linear stiffness ratio of upper columns and lower columns, axial compression ratio.The result can provide references for the practical application and scientific research of CFST-RC column connection of imitated ancient buildings, and lay a foundation for the further research of imitated ancient building structure.