Research On The Performance Of Cold-formed Thin-walled C Steel Composite Column Under Compression-bend Load

Cold formed steel as a main part of principal bearing element, has been widely used in the low-rise dwelling, forming the cold-formed steel structure system. The research is focus on analysis thecompression-bending members with composite section of the cold-formed thin-walled C steel byusing experimental study, theoretical analysis and finite element simulation.In the paper, nine cold-formed thin-walled C steel composite column were tested in monotonicloading, the failure modes and the ultimate bearing capacity were analyzed, also along with theimpart of eccentricity, gusset plate thickness, gusset plate spacing and slenderness ratio on themechanical behavior of specimens. Section type is double C back-to-back, with gusset plateconnecting with high-strength bolt in the middle. The results of the experiments showed that thefailure modes are in-plane flexural buckling and local buckling of the flanges and webs of thespecimens under pressure. The influences of different parameters on the mechanical behavior ofspecimens has been achieved by making comprehensive analysis and comparison of the stabilitybearing capacity, displacement and stain distribution of specimens slenderness ratio, eccentricityand gusset plate spacing are the major factors that influence the bearing capacity and stiffness, whilethe gusset plate thickness has no obvious impact.Besides the paper is giving an analysis to the changes in stiffness from loading process,analyzing the impact of different parameters on the stiffness of specimens. From the analysis, therelationship between specimens stiffness and axial load changes, as well as the moment-curvaturecurve have been established. The theoretical value of the stability bearing capacity of specimens hasbeen reached by calculating with the effective width method in the GB50018-2002.At the same time,the correction coefficient of calculation method for bearing capacity of section component isproposed. And comparisons among test bearing capacity, theoretic bearing capacity and modifiedbearing capacity have be made.This report is basing on the experimental study, combining with the finite element analysis software ANSYS10.0to built a3D parametric finite element models of component to achieve thesimulation resultes. In the end, by comparison the simulation results with experimental results showsthat the simulation method is ideal, and experimental results is better matching for the simulationresults.