The local scour of the bridge foundation is one of the main factors which leads to the washout of bridge.Based on the hydro-geological data of a large Yellow River bridge,the RNG k-εturbulence model is used to calculate the pile group foundation of trestle bridge based on the hydrodynamics module and sediment transport module of Flow-3D software.The influence of flow velocity and pile diameter on the local scour of pile group foundation is analyzed,the equilibrium scour pit shape is obtained,and the time-history variation mechanism of scour depth is revealed.The results show that the maximum erosion depth of pile group foundation increases rapidly in the early stage,increases slowly in the middle stage and tends to be flat in the late stage.The erosion pit on the head water side pile foundation develops strongly,and the depth and scope of the erosion pit are much larger than that on the rear pile foundation,mainly because the water flow in front of the rear pile foundation is weakened by the block of the waterside pile foundation.The maximum scouring depth of pier increases significantly with the increase of flow velocity,and increases approximately linearly with pier diameter.
关键词
桥梁工程/群桩基础/基础局部冲刷/水流速度/数值模拟研究
Key words
bridge engineering/pile group foundation/foundation local scour/flow velocity/numerical simulation study
万方数据