Study On Behavior And Load-Carrying Capacity Of Concrete-Filled Tubular Column To Steel Beam Connections

Along with widely spread use of CFST (concrete-filled steel tube) structure, people have been paid more attention to the design of CFST joint. Institutes inland process massive research on CFST joint, most of them were aim at joint style, but the CFST column connected beam have a lot of questions, need to study deeply.In this paper, we study the CFST joints with stiffening ring which were recommended by the national criterion. By using universal finite element analysis program: ANSYS 8.1, we carry finite element analysis on enforced loop joint of CFST. Compared with result of experimentation, finite element model can simulate real structure effectively. Through ten F.E. models, study on enforced loop plane from five aspects:(1) width of enforced loop plane;(2) thickness of enforced loop plane;(3) thickness of steel tubular;(4)axial load,(5) model of load. The analytical result is : With width and thickness of enforced loop plane increased, the bearing capacity of joint has been improved obviously. So width and thickness of enforced loop plane is important factors that affect bearing capacity of joint. As thickness of steel tubular increased, loading capacity has been few improved, so thickness of steel tubular is not important factor. When put axial load on column, stress of enforced loop plane has been improved. Stress maximum value has been increased, the maximum is less than stress on final load, axial load contribute to loop stress value relatively lightly, thus needn't consider affecting on joints. Finally, according to analysis on theory, put forward the design method. The design method is simple. It is valuable method for design of CFST structure.