舟山册子岛-镇海海底管道附近海床冲淤数值模拟研究

舟山册子岛-镇海段海底原油管道连续多年监测数据显示,局部海床冲刷较为严重,管道多处裸露、悬空,对工程安全构成威胁。基于Delft3D建立杭州湾口二维水流泥沙数学模型,并利用实测潮位、流速、流向及悬沙质量浓度资料对模型进行率定与验证,进而模拟分析近年来人为开发活动对海底管道附近海床冲淤变化的影响。分析结果表明,新泓口围垦工程和金塘大桥工程对管线镇海登陆段海床冲刷影响较大,金塘大桥桥墩阻水作用加剧了管线深槽边坡西半段海床的冲刷,另外管线深潭延伸东半段的海床冲刷与金塘大桥主通航孔密切相关。

Simulation analysis on scouring and silting stability of the seafloor with submarine pipeline from Cezi Island to Zhenhai

According to the monitoring data over consecutive years for the seabed where submarine pipeline is from Cezi Island to Zhenhai, the results indicate seriously scouring phenomenon. For the purpose of making analysis about human activity influence, a two-dimensional numerical model was set up to simulate hydrodynamics and sediment environment of the Hangzhou Bay with Delft3D. This model had been calibrated and validated with observed data of tidal level, currents and suspended sediment concentration. The results show that the reclamation in Xinhongkou of Zhenhai and Jintang Bridge have a great impact on the seabed scouring of the landing position in Zhenhai. The results also show that the water-blocking effect of Jintang Bridge could aggravate the seabed scouring of the slope position in scouring channels, and that the seabed scouring of the extension position in deep pools is closely related with the main navigable hole of Jintang Bridge.