Study On Wind Stability And Optimization Of Continuous Rigid Frame Bridge With Long-Span And Super High Piers

As computing technology improved, new material application and constructiontechnology improved, the bridge span become larger and the problem of stability andwind is increasingly outstanding. The top of large span continuous rigid frame bridgewith high pier, which is distributed in the coastal and mountain gorge section, willhave very big wind speed. Thus, the static and dynamic wind load on the continuousrigid bridge is large. And this kind of bridge has a high, light, soft features, which ismore sensitive to wind load. Therefore, the problem of the stability and resistance tothe wind is very necessary to further study. Based on Hezhang super-large bridge, thepaper research on the wind stability and optimization.Firstly, a reference to "Hezhang super-large bridge structure parameters of windload" report and "the wind-resistant design standard of the highway and bridge"(JTG/T D60-01-2004), the paper calculates horizontal and vertical static wind load onthe main girder and pier construction stage and finished stage. Then, based on theWAWS method, the paper organizes the stochastic wind speed time-history programwith modified Fourier spectrum method, simulates the Hezhang super-large bridgehorizontal, vertical wind speed time-history, and makes wind speed spectrum test.Secondly, the cantilever construction stage and finished stage finite elementmodel of Hezhang super-large bridge are established respectively by using finiteelement analysis software ANSYS and Midas/Civil,and verifies the accuracy of gridand grid convergence.Thirdly, the paper carries out static linear and nonlinear stability calculation onthe three construction conditions, in which the nonlinear stability load gradient isexerted by uniform load and concentrated load.Fourthly, Research aerostatic stability on the horizontal tie beam, section type,net spacing of the battened piers. Slope ratio and structural form impact on the staticwind stability.Fifthly, dynamic characteristics of the maximum cantilever stage80m,195mhigh pier and finished stage are analyzed. Comparison of the Hezhang super-largebridge buffeting response and static gust response results, find fluctuating amplifying coefficient in the maximum cantilever stage construction is larger than finished stage.That is to say, the maximum cantilever construction stage is more sensitive tofluctuating wind load. Therefore, the construction stage should be attracted moreattention.Finally, the paper summarizes the research work, come to some conclusions, andpoints out the further suggestions.