Large-span steel structure is widely used in modern buildings because of its advantages such as light weight and high strength, but its large span and small damping characteristics make it prone to excessive deformation and dynamic response under wind load. This paper takes a large-span steel truss structure of a stage play as an example, analyzes the dynamic characteristics of the wind-resistant performance of the large-span steel structure by using the finite element method and puts forward an improved design scheme. The study adopts 3D3S and ANSYS software to establish a finite element model of the steel structure, and analyzes the static and dynamic responses of the structure in different wind directions and wind speeds, and explores the effects of wind loads on the structural displacements, static three-dimensional forces and stability. The results show that: when the wind speed reaches the critical value of 170m/s, the transverse displacement in the span of the main girder increases from 41.22mm to 66092.45m, presenting the phenomenon of displacement dispersion, and the structure is destabilized and damaged; the structural instability pattern varies in different wind angles of attack, with a combination of spatial bending and torsion in the angle of attack of 0°, and mainly transverse bending instability in the angle of attack of ±5°; and the results of the component load bearing capacity calculation show that The results of load capacity checking show that all the main steel members of this project meet the performance target of not yielding under the action of 16.5 grade typhoon. Based on the analysis results, the study proposes the improved design scheme of using triangular tube truss columns and beams to form a spatial portal transverse bearing whole, and optimizes the key construction technology, which effectively improves the wind resistance performance of the structure and provides theoretical basis and technical support for the wind resistance design of large-span steel structures.
