Analysis On Whole Stability Of The Thin-walled Steel Member

Along with the extensive application of light steel structure, the efficient economicprofiles–Cold formed steel began to be universal concern in the engineering sector athome and abroad, especially in light steel housing construction have becomeincreasingly widespread. The emergence and application of cold-formed steel, hasopened up a new way to improve material utilization, to a large extent saves the energyand resources, and has great environmental significance. But the thin-walled steelmember also has its drawbacks, the characteristics of its high strength, slender bodymakes the stiffness is low, easy to instability in the force. Therefore, the stability of thecold-formed steel structural design is particularly important.In this paper, the system is divided into strength members and an open thin-walledbar in the analysis of the open thin-walled bar with stiffening members. By Vlasov’sclassical theory and Kollbrunner-Hajdin’s longitudinal warping displacementassumption, as well as strengthening the component, the reinforcing member can beregarded as an elastic support on the role of the lever member, so as to create thecalculation model of analysis of the bars.The torsion analysis calculation model of cold-formed thin-walled bar isestablished on the assumption, by introducing the dual variables, considering thesolution system from the Lagrange system Hamiltonian system, and derived theHamiltonian equations of the dual, and then using the precise integration method at bothends of Boundary and the dichotomy to obtained the accurate numerical solutions indifferent cross-sectional form of the critical load. In the calculation process to takeadvantage of the consistency theory to get the Hamiltonian dual equations which hasbeen applied to both open, closed, and mixed section, and obtained the critical load ofthe opening of cold-formed steel members with a reinforcing member.This method is clear thinking, high precision and can be applied to a variablecross-section as well as in the stability analysis of the components of the complexexternal force state, for the study of such works to provide a new method has a certainreference value to the project.