EXPERIMENTAL RESEARCH ON RESISTING PUNCHING BEHAVIOR OF THE COLUMN FOOTING NODE OF CFST COLUMN WITH STUDS

It was studied the punching failure mechanism,position of blunted cut,and the influence of punching bearing capacity factors of node of the column footing in beam form of CFST column with studs embedding in the reinforced concrete foundation under static loading through quasi-static method.The research showed that punching area of the concrete extended because the upper edge of punching area moved from the bottom of steel tube to the highest studs,which improved the bearing capacity of resisting punching of the component after welding studs outside the steel tube.When the number of the studs is enough and their layout is reasonable,the bearing capacity of resisting punching of the column footing can be greater than the capacity of resisting shear.The safety of the components can be ensured if the column footing node meets the flexural and shear requirement.