The Response Of Buffeting And Flutter Vibration Analysis Of Arch-tower Cable-stayed Bridge

The aim of wind induced vibration analyses for bridge is to study its aerodynamic and aerostatic stability and to find its buffeting responses so as to avoid wind instability and to ensure the buffeting amplitude within a permissive range for structural safety and amenity.The research of this paper is related to an arch-tower cable-stayed bridge.In this paper,anti-wind capability,especially the response of static wind,aerostatic stability and response of buffeting response of the bridge is studied.The main works are the following:1. The brief introduction of the research of wind induced vibration, the research issues of bridge anti-wind, the basic analysis theories of static forces and buffering of bridge are all presented briefly.2. The introduction of the theoretical studies and simulation methods of the nonlinear dynamic analysis of cable-stayed bridge.The model of the cable-stayed bridge considered the geometric nonlinearity is established, and then the reasonable state of the bridge is found.The structural dynamic characteristics of the bridge are analyzed.3. The static wind response of the bridge is analyzed.In the analysis of static wind response for cable-stayed bridge, through imposing static wind load to bridge, bridge structure displacement response and internal force response under three different stages, bridge states, largest single-cantilever state and largest double-cantilever bridge were calculated.4. Nonlinear aerostatic stability analysis is put into practice for cable-stayed bridge by the modified increment and inner-outer iteration method and time domain analysis method,defined the types of aerostatic instability of cable-stayed bridge and discussed the aerostatic instability configuration,mechanism of aerostatic instability,and the mutual effect between buffeting responses and aerostatic stability.5. The analysis results of response of static wind and buffeting in different construction stages are gathered and compared.Some useful conclusions in this research are given. Through this study, the wind resistant characteristics of arch-tower cable-stayed bridge are recognized more clearly, and the computing theories and methods of bridge response of static wind, aerostatic stability and response of buffeting are understood.This research should have instruction meaning for the future similar bridges'design.