Torsion and Shear Behavior Study of Hollow and Solid Concrete Filled Steel Tubular (CFST) Members II:Theoretical Research on Strength

Currently,the concrete filled steel tube(CFST) structures have been widely used,but the calculation of shear and torsion capacity is starting from FEA or testing,then getting regression formulas or empirical formulas.In this paper,firstly the torsion resistance of CFST is studied by theory,then the formulas of shear strength and shear resistance are obtained based on "unified theory".At last,the proposed method is verified by experimental data and existing research results,which shows the feasibility of this theoretical formula.