Wind-Induced Buffeting Time-Domain Analysis For Combined Highway And Railway Steel Truss Cable-Stayed Bridge

With the development of science and technology, the cable-stayed bridge is gradually developing into long span and deck more flexibility, but the wind-induced vibration of the bridge has also become an issue can not be ignored. The wind-induced vibration of bridge not only have significant impact on the stress of key section of the bridge and fatigue properties of the structure, but also have adverse effects on driving comfort at the using stage and safety at building stage. Buffeting is one of extremely important limit amplitude vibration, which has two method named frequency-domain simulation and time-domain simulation to analyze. Time-domain simulation plays a momentous role in buffeting analysis.In this thesis, taking one combined highway and railway steel truss cable-stayed bridge as the background, linear time-domain buffeting analysis at using and building stage is studied. The major work is shown as follows:1. According to the characteristics of the deck and tower, three-dimensional fluctuating is simulated.2. Buffeting force of key section of bridge calculated by using Scanlan’s quasi-steady aerodynamic theory. A set of code which is easy to load the buffeting force on model in ANSYS is compiled.3. The simplified model of combined highway and railway steel truss cable-stayed bridge is built in ANSYS, which used to make the modal analysis and buffeting analysis of the model.4. Making the linear buffeting time-domain simulation analysis for the deck and tower to calculate the internal force and displacement of the key sections of bridge.5. According to the result of this thesis, some conclusions that have certain reference value in engineering are summarized.