崖门出海航道大风天泥沙骤淤分析

An analysis of sediment sudden siltationin in Yamen waterway in storm condition

崖门出海航道穿越黄茅海,是银洲湖出海的主要通道.通过对黄茅海风浪情况和海床泥沙特性的分析,认为崖门航道存在大风天发生航道骤淤的可能性.采用经验公式估算的方法,对崖门东线和西线航道在同等工况下的底沙、悬沙淤积进行了计算.在"三碰头"(风、浪、流)水情作用24 h后,东线航段平均淤浅0.15 m,最大淤厚0.30 m;西线航段平均淤浅0.30 m,最大淤厚0.62 m.西线航道骤淤的可能性和幅度都要大于东线航道,这主要在于西线航道处在黄茅海中口门的开阔海域,而东线航道途径水域则有众多岛屿对风浪的掩护作用.在崖门出海航道的开发过程中,西线航道大风天形成的骤淤应予以特别重视.

Yamen waterway passes through Huangmao sea. This is a main channel from Ngan Chau Lake to the sea. Results from wave climate and bedload characteristics analysis show that the high and rapid of back siltation appeared in the Yamen navigation channel in storm condition. Bedload and suspended sediment deposition in the east and west channel under the same conditions can be estimated by an empirical formula. Under the effect of simultaneously of ＂three main factors＂ （wind, wave and flow） for a whole day and night, the average siltation thickness of the east waterway is 0.15 m and the maximum thickness is 0.30 m, while in the west waterway is about O. 30 m and 0.62 m, respectively. The possibility of sudden siltation and ranges in the westem channel are much greater than the eastern channel. This is due to the west waterway is located in the open sea of Huangmao Sea. However, the east waterway passes through many islands which are covering against the storm. In a period of development of Yamen navigation channel, the sudden siltation in the west channel under heavy storm conditions should be paid a special attention to sudden sileation during the development of Yamen waterway.