This paper, after briefly reviewing the experimental research on sediment transport on muddy beach since the 1950s, improves and perfects the method for forecasting siltation in navigation channels and harbour basins ...This paper, after briefly reviewing the experimental research on sediment transport on muddy beach since the 1950s, improves and perfects the method for forecasting siltation in navigation channels and harbour basins which was first put forward in China by the authors. In consideration of silty sediment and sand, some factors in forecasting methods have been changed and modified. Consequently, the modified methods can be used either to compute siltation in navigation channels and harbour basins on muddy beach or to compute siltation and scouring in navigation channels and harbour basins on both silty beach and sandy beach. The verification of field data from eleven large, medium and small natural harbours shows a good agreement between the forecasting by the modified method and the natural conditions. Finally, the paper deals with the rational utilization of water area after the construction of the West Dyke in Lianyungang, the maintenance of water depth of the navigation channel at the entrance, siltation distribution, siltation in the navigation channel and harbour basin for ships of 100 thousand tonnnage. Results once again prove that the prospect of constructing Lianyungang Harbour into a deepwater harbour is bright.展开更多
5. Application and Popularization of Computational Methods for Siltation The above mentioned computational method covers siltation in navigation channels andharbour basins on muddy beach. This part mainly deals with t...5. Application and Popularization of Computational Methods for Siltation The above mentioned computational method covers siltation in navigation channels andharbour basins on muddy beach. This part mainly deals with the possibility of its application tosilty beach and sandy beach and the computation of scouring. The following discussion involvestwo aspects, and then some computational examples are given.展开更多
A practical model has been developed for the propagation and decay of random waves on muddy beaches. In the model, an irregular wave train is characterized by its root-mean-squared wave height, mean wave frequency and...A practical model has been developed for the propagation and decay of random waves on muddy beaches. In the model, an irregular wave train is characterized by its root-mean-squared wave height, mean wave frequency and mean wave direction. It is also assumed that the wave spectrum is narrow-banded in terms of both frequency and direction. Transformation of root-mean-squared wave height is derived from the conservation of energy flux for individual wave components. Energy dissipation is considered due to both wave breaking and the dynamics response of muddy seabed. The model is applied to waves on the muddy beach at Hangzhou Bay, and the numerical results obtained are shown to be acceptably accurate as comparing with available field data.展开更多
Based on field investigations, this paper analyzes three types of harbour basinns and navigation channel excavated on seabed in Jiaozhou Bay, get a general rule of deposition for excavated trough, it found that pollut...Based on field investigations, this paper analyzes three types of harbour basinns and navigation channel excavated on seabed in Jiaozhou Bay, get a general rule of deposition for excavated trough, it found that pollution is one of crucial factors resulting in the deposition of the excavated trough in the east shore of Jiaozhou Bay. With these results, it predicted the annual deposition thickness for the excavated trough and disclosed the fact that it can't be deposited deadly during one storm. At the same time, with two-dimensional numerical model, it studied the effects of the excavated trough and the reclamation near shore on tidal cureent and said that the excavated trough can decrease the current velocity passing through the trough about 10- 15%, but only limited inside and near the trough and there are no effect on other regions; reclamation can cut off the pollution sources and no obvious effect on the currents of the Jiaozhou Bay. Connecting the deep trough and Cangkou tidal channel with a new excavated trough can improve the current conditions on the deep trough in some degree, but not great.展开更多
文摘This paper, after briefly reviewing the experimental research on sediment transport on muddy beach since the 1950s, improves and perfects the method for forecasting siltation in navigation channels and harbour basins which was first put forward in China by the authors. In consideration of silty sediment and sand, some factors in forecasting methods have been changed and modified. Consequently, the modified methods can be used either to compute siltation in navigation channels and harbour basins on muddy beach or to compute siltation and scouring in navigation channels and harbour basins on both silty beach and sandy beach. The verification of field data from eleven large, medium and small natural harbours shows a good agreement between the forecasting by the modified method and the natural conditions. Finally, the paper deals with the rational utilization of water area after the construction of the West Dyke in Lianyungang, the maintenance of water depth of the navigation channel at the entrance, siltation distribution, siltation in the navigation channel and harbour basin for ships of 100 thousand tonnnage. Results once again prove that the prospect of constructing Lianyungang Harbour into a deepwater harbour is bright.
文摘5. Application and Popularization of Computational Methods for Siltation The above mentioned computational method covers siltation in navigation channels andharbour basins on muddy beach. This part mainly deals with the possibility of its application tosilty beach and sandy beach and the computation of scouring. The following discussion involvestwo aspects, and then some computational examples are given.
基金the National Natural Science Foundation of China (Grant Nos.10772099,50221903)
文摘A practical model has been developed for the propagation and decay of random waves on muddy beaches. In the model, an irregular wave train is characterized by its root-mean-squared wave height, mean wave frequency and mean wave direction. It is also assumed that the wave spectrum is narrow-banded in terms of both frequency and direction. Transformation of root-mean-squared wave height is derived from the conservation of energy flux for individual wave components. Energy dissipation is considered due to both wave breaking and the dynamics response of muddy seabed. The model is applied to waves on the muddy beach at Hangzhou Bay, and the numerical results obtained are shown to be acceptably accurate as comparing with available field data.
文摘Based on field investigations, this paper analyzes three types of harbour basinns and navigation channel excavated on seabed in Jiaozhou Bay, get a general rule of deposition for excavated trough, it found that pollution is one of crucial factors resulting in the deposition of the excavated trough in the east shore of Jiaozhou Bay. With these results, it predicted the annual deposition thickness for the excavated trough and disclosed the fact that it can't be deposited deadly during one storm. At the same time, with two-dimensional numerical model, it studied the effects of the excavated trough and the reclamation near shore on tidal cureent and said that the excavated trough can decrease the current velocity passing through the trough about 10- 15%, but only limited inside and near the trough and there are no effect on other regions; reclamation can cut off the pollution sources and no obvious effect on the currents of the Jiaozhou Bay. Connecting the deep trough and Cangkou tidal channel with a new excavated trough can improve the current conditions on the deep trough in some degree, but not great.
