Study On Rotational Constraints Of Plated Column Base To Axially Loaded Column

At present, according to Code for design of steel structures(GB50017-2003),for axially loaded column with plated column base, the column bases are considered as hinged supports, without consideration of the rotational restraint to the column. But it has been proved that the plated column base possess remarkable rotational restraint according to the deduction of theory and experiments.To study the rotational restraint of plated column base to the column, H-section columns with plated column base were studied through experiment in this paper. The moment-rotation curves of the column base were obtained, the influence factors on the rotational stiffness of plated column base, such as the base plate thickness,the number of anchors,the slenderness ratio were studied and the influence to the effective length factor of rotational stiffness were also studied through the experiment; The paper established the plated column base models with the finite element software of ANSYS, analyzed the test specimen with the models and compared the finite element results with experimental results to verify the models being accurate. On this foundation, analyzed the influence factors on the rotational rigidity of the plated column base, such as base plate thickness, the number and diameter of the anchors, column section size, still grade and Concrete strength grade .The paper proposed the formulas of the rotational rigidity of the plated column base according to the experimental results, and deduced the relationship between the rotational rigidity of the plated column base and the effective length factor. The influence factors on the effective length factor such as the base plate thickness, the slenderness ratio, column section size and elastic modulus of concrete were studied based on the calculation of effective length factor of the specimen.