Analysis Of Wind-Induced Response Of Rail-Cum-Road Cable-Stayed Bridge And Train Overturning Stability Of Train On Bridge Under Cross Wind

As more and more bridge damage caused by wind-induced vibration, much more attention has been paid on the effects of wind on bridge structure. Nowadays, with the widely use of long span rail-cum-road bridge and the acceleration of train speeds, safety problems of train running on bridge have deserved general concerns. Thus, it is great important to do the research on wind-induced vibration of bridge and train overturning stability on bridge. In this dissertation, CFD numerical simulation and wind tunnel model test are used to research the aerodynamic characteristics of the bridge system and analysed wind-induced response of rail-cum-road cable-stayed bridge. The main contents are as follows:1. Combined with the characteristics of the wind at bridge site, the three-dimensional wind field is simplified into three separated wind field by Harmony Superposition Method. The wind field simulation results are tested, it shows that the results are good.2. The finite element model is built by finite element analysis software-ANSYS and the static wind and buffeting response of bridge are calculated.3. Study on the changes of aerodynamic characteristics of bridge system under different traffic flows. At first, the aerodynamic characteristics in different traffic flows are measured with wind tunnel model test, it was shown that when small cars are running on bridge, the drag force of bridge system does not increase with the increasing of traffic density, Then, the same conditions were simulated by CFD numerical simulation method, the similar results were obtained. It seems that the presence of vehicle makes a smooth effect on the configurations of the bluff bridge section.4. Research on the aerodynamic characteristics of the train-bridge system under different wind angles of attack and heights of wind barrier by CFD numerical simulation method.5. Study of the train overturning stability on bridge under cross wind, the overturning critical wind speed of train is calculated. It shows that the setting of wind barrier is beneficial to the safety of train running.