桥墩局部冲刷数值模拟及冲刷深度计算方法对比研究

Numerical simulation of local scour of bridge piers and comparison of calculation methods of scour depth

随着国家海洋强国战略的推进,跨海大桥建设已成为连接地区经济发展的关键。桥墩冲刷是威胁桥梁安全的重要因素,正确理解冲刷过程与预测冲刷深度可为实际工程前期设计和运营维护提供指导。文章基于REEF 3D数值模式模拟了3个实际工程桥墩的局部冲刷过程,对桥墩周边的流场及冲刷特征进行了分析。在此基础上利用规范、经验公式以及不同工况下海上风机单桩冲刷计算公式预测桥墩冲刷深度,通过对比分析不同计算方法下的局部冲刷深度结果,给出不同水深下冲刷深度计算方法的选取建议。

With the promotion of the national marine power strategy,the construction of deep-water cross-sea bridge has become the key to connect regional economic development.Pier scour is an important factor threatening the safety of bridge.The correct understanding of scour process and prediction of scour depth can provide guidance for the actual engineering design.Based on the REEF 3D numerical model,the local scour process of three engineering piers was simulated,and the flow field and scour characteristics around the piers were analyzed.On the basis of numerical simulation results,the scour depth of bridge pier was predicted by using national norms,empirical formulas and scour formulas of offshore fan under different conditions.Through the comparison and analysis of scour process and scour depth results under different calculation methods,the selection suggestions of scour depth calculation methods under different water depths are given.