Numerical Simulation Of The Wind Environment On Bridge Deck Near The Pier And Tower In Cross Wind

Sea-Crossing Bridge is often in the strong crosswind environment. The flow over struetures may lead to abrupt change of wind speed, which is disadvantage to traffic safety.To explore the wind environment around the pier and tower and the effect of wind barrier in the area, a box girder bridge and a truss bridge are studied in this thesis. This thesis carried out relevant research as follows:1. By using the computational fluid dynamics technology (CFD) and analysis Platform of FLUENT, numerical simulation of the box girder bridge was carried out. Preliminary analysis of the influence law of bridge pier was conducted by means of wind cloud chart and 3D wind distribution map. Wind profiles of different lanes were made a comparison to research the effect of wind barrier around the pier. Influence area in the bridge axial direction and height direction was discussed according to the changes of wind along the bridge.2.3D model of the truss bridge is made by FLUENT. Through trial calculation and wind tunnel test data, calculated parameters were determined and wind environment above the deck was calculated under different working conditions. The impact area of tower on the highway deck and railway deck was analyzed. The impact of ventilation rate of wind barrier to the wind environment around the tower was discussed. The reliability of calculation was verified compared with wind tunnel test results.Research on the pier shows that wind speed decreases on the bridge deck near the pier. The influence area of pier on wind environment becomes narrowing as height increases. The difference of the wind field distribution rule above the deck induced by the change of wind speed is quite limited. Significant effect due to the ventilation rate of wind barrier and guardrail is showed on the windward side of deck, which is indifference on the leeward side. Abrupt change of wind speed is weakened by the wind barrier, on the other hand it reduced the wind speed.Research on the tower shows that wind speed on the highway deck without wind barrier increases sharply on both sides of the tower, and then becomes flat. The farther away from the bridge tower, the effective height of wind barrier is higher. The influence area of tower on the highway deck and railway deck with wind barrier respectively is 25m and 15m on both sides of the tower. Change of wind speed is more abrupt if ventilation rate of wind barrier is smaller on the highway deck.