Research On The Mechanical Behavior Of Crisscross-shaped Concrete-filled Steel Tube Stub Columns With Binding Bars

As to the binding force exerted on the core concrete by the tube wall, the ordinary special-shaped steel-tube is smaller than the round steel-tube. In order to improve the force bearing quality of special-shaped steel-tube, the construction department of South China University of Technology cooperated with Guangdong Architecture Designing Academy and propose a new type of assemble configuration. They also carry out the systematic experimental research and theory analysis of the basic dynamic capacity under the axis pressure and deflecting pressure. In the new configuration, the horizontal binding pull rod is established intermittently and vertically in the the column of special-shaped steel tube section (square, rectangle, L-shaped, T-shaped, crisscross-shaped), so the drawing force of binding rod will strengthen the binding effect of the tube wall to concrete and improve the force bearing quality of the special-shaped steel tube.As one part of the serials of research on the special-shaped steel tube with binding pulled bars, this paper mainly focuses on the concrete column of crisscross-shaped steel tube and make a further research on its dynamic capability under the load of axes. On the basis of sisteen model experiments and non-linearity limited analysis of axes press short column, the research is done to analyze how the diameter, the horizontal space between the pulled bars and the ply of the tube wall will effect bearing capacity and ductility. The crisscross-shaped steel-tube concrete rod's working capability and breakage mechanism under the pressure of axes pressure is also studied. Drawing on the present available binding concrete construct relation model and combining with experimental data to have a mathematical analysis, we put forward an analytic formula of material construction relation model of binding crisscross-shaped concrete steel-tube, and have a whole-process analysis of loading-distortion to the crisscross-shaped concrete steel-tube with binding pulled-bars. What's more , the simplified calculating method of axes pressure bearing force is also given. At last the paper makes an elementary study and research to the local buckling of the steel-tube with the crisscross-shaped binding pulled bar.