Study On Properties Of Exposed Cast Steel Column Base

With the development of steel structure, the production of usual column bases isincreasingly standardized, and the research of them also gradually goes deep. But theresearch of the exposed type, another familiar column base, is standstill.This study is aimed at a simple exposed cast steel column base, especiallymechanical performance analysis, in order to get the mechanical performance of theoverall structure. First, analyze the theory of the force-deformation curve, and checkthe finite element model by a four anchor bolt exposed cast steel column base. Second,study the influence factors of column base: Anchor bolt diameter and position, platethickness, concrete floor thickness etc. At last, match a M-θ curve on column base,draw hysteresis curve in different factors and get overall performance in framework.Although the column base connection appears in the Chinese design code forsteel structures (GB50017-2003), it is limited to the calculation length of column base,and the design for steel column foot isn’t regulated.1) Exposed cast column base is similar to embedded type in mechanicalproperties and the seismic energy dissipation capacity under axial pressure. Comparedto embedded type, the exposed type could save a lot of manpower and material costswith less degrade performance.2) The mechanical property of exposed costcolumn base is influenced by axialcompression ratio, anchor bolt diameter and position, anchoring depth, plate thicknessand concrete foundation. The optimal compression ratio is about0.6for square steelcolumn when the safety and economy are both in ideal state.3) Both anchor bolt damage and floor damage are plastic failure in exposedcolumn base. The anchor bolt is the most main factor for a sharp decline appearswhen the anchor bolt diameter reduces. In design, the yield of anchor bolts is asked toappear after floor as well as the anchorage of anchor.4) The form of exponential equation could be used in the design of exposed costcolumn base, also can be used as a reference.