汕头湾海底隧道工程河段最大冲刷深度研究

Study on Maximum Scour Depth at River Reach of Shantou Bay Subsea Tunnel Project

通过河工模型试验,研究汕头湾海底隧道工程河段的水流流态和河床冲刷情况,对不利水文条件下的隧址河床最大冲刷深度进行了分析。成果表明,在不利水文条件下隧址断面最大洪水流速达1.5 m/s以上,左右两汊主槽河床冲刷明显。300年一遇、100年一遇水文条件下隧址河床最大冲刷深度分别为6.40、5.24 m。隧址断面最大冲深的包络线成果可为工程的合理埋深提供依据,研究成果可为汕头湾类似工程提供参考。

This paper studies the flow pattern and riverbed scouring at the river reach of Shantou Bay Subsea Tunnel Project through the river model test and analyzes the maximum scour depth of the riverbed near the project under unfavorable hydrological conditions.The results show that the maximum flood velocity at the tunnel section is above 1.5 m/s under unfavorable hydrological conditions,and riverbed scouring is obvious in the main channels of the left and right branches.The maximum scour depth of the riverbed at the tunnel site is 6.40 m and 5.24 m under the once-in-three-century and once-in-a-century hydrological conditions,respectively.The envelope results of the maximum scour depth at the tunnel section can provide a basis for determining the reasonable buried depth of the project,and the research results can provide reference for similar projects in Shantou Bay.