Study Of Aerostatic Stability For Long-Span Cable Supported Bridge

With the increase of bridge span, the quality of bridge structure is getting lighter andlighter, structure stiffness getting smaller and smaller, structure damping getting lower andlower, which result in the sensitivity of wind-induced effect is increasing. In recent years, thewind tunnel tests and research results show that long-span cable supported bridges exist thepossibility of aerostatic instability. Therefore, it is necessary to conduct a comprehensivestudy on the aerostatic stability of long-span cable supported bridges. With comprehensiveconsideration of the nonlinearity of the structural geometry and static wind load, this paperused bridge deck’s aerostatic force coefficients measured by wind tunnel test to analyze theaerostatic stability for long-span cable supported bridges, and reveals the general law ofaerostatic instability; by changing the parameter investigated its influence on the aerostaticstability of long-span cable supported bridges, and obtained must be considered factors andcan be ignored factors in the analysis, which provide the basis and reference for the anti-staticwind design. In this paper, the main research work carried out the following:1Introduced the linear methods of aerostatic stability analysis, expounded the nonlinearfactors of aerostatic stability, and mainly described several kinds of nonlinear analysismethods of aerostatic stability analysis;2Based on the nonlinear aerostatic stability theory for long-span cable supported bridges,the analysis of aerostatic stability was realized in ANSYS and the related calculation programwas compiled and generalized by APDL, which can be applied to other cable supportedbridges;3Through the section model wind tunnel tests measured the deck’s aerostatic forcecoefficients of Humen Two Bridges, and analyzed its aerostatic stability used the calculationprogram, then discussed the morphology and mechanism of aerostatic instability;4The influence of aerostatic stability was studied by different parameters, includingaerodynamic coefficients, the initial wind attack angle, bridge tower wind load, cable windload, and the side span wind load.