Research On Behavior Of Short Column Reinforced By Inner Circular Steel Tube With Outer Angle Steel Plank Under Axial Compression

The short column reinforced by inner circular steeel tube with outer angle steel plank is a new type of steel-concrete composite structures, the evolution and development of this composite column is based on the lattice type steel reinforced concrete column and core steel-tube reinforced concrete column rised in recent years. Compared with the core steel-tube reinforced concrete column, the new type composite column has better properties, the shear properties, bending properties, torsion properties and tensile properties of compression strength have been enhanced greatly, the ductility and toughness is improved largely, because of the core steel tube and angle steel plank restraints on the concrete of inside and outside of the core steel tube.The effective finite element models are established, using of finite element software ANSYS. The properties of the short column reinforced by inner circular steeel tube with outer angle steel plank in axial compression are numerically simulated.For the main parameters: concrete strength, angel steel intensity, angel steel ratio, steel pipe intensity, steel pipe ratio, location factor and so on, the properties and failure modes of the composite column in axial compression are analysed, according to the whole process of nonlinear finite element numerical simulation. The basic assumptions and calculation formula of bearing capacity of the composite column in axial compression are presented, which for the hoop constrainted composite column and battens constrainted composite column. The calculated results agree well with the experimental results.According to the mechanical characteristics of the composite columns, The basic assumptions and calculation formula of composite stiffness of the composite column in axial compression are presented, which separates the composite column into outer steel plank with concrete, and the steel tube with concrete filled. The results agreed well with experimental results.