检索结果-南通市图书馆

Regulation of navigation channel on Mouth Bar of Guanhe Estuary

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 1994年第3期9卷 355-364页

作者： Li Guochen Associate Professor, Hohai University, Nanjing 210024

-Based on the feasibility study of developing the navigation resources of the Guanhe River and the model test results of the mouth bar regulation, this paper presents some basic principles for the regulation of the channel on the mouth bar, for instance, the direction of navigation channel should be identical with that of the ebb tide current and the main waves, and perpendicular to the bathymetric contours. The principles for regulating mouth bars are also discussed in this paper.

关键词： regulatiton navigation channel mouth bar estuary alignment of channel

NUMERICAL SIMULATION OF DEPOSITION IN THE TEMPORARY navigation channel OF THE THREE GORGES PROJECT

在线全文

学校读者我要写书评

暂无评论

NUMERICAL SIMULATION OF DEPOSITION IN THE TEMPORARY NAVIGATI...

Exploration of the Mechanisms for the Low Sensitivity of Deposition Flux to Upstream Sediment Reduction in the North Passage, Yangtze Estuary

第九次河流泥沙国际学术大会

作者： Chunming FANG Wenhong CAO and Wen LUChina Institute of Water Resources and Hydropower Research Beijing 100044 China

＜正＞Sediment deposition in the temporary navigation channel of the Three Gorges Project was significant, and dredging was carried our each year. Sedimentation in the temporary navigation channel is similar to sedimentation in the permanent navigation channel a few decades later when the sedimentation processes in the reservoir comes to quasi-equilibrium. Study of the sedimentation processes is therefore of practical interests. By applying a depth-integrated 2-D model to the river reach near the dam and a vertical 2-D density flow model to the temporary navigation channel, the sedimentation processes in the channel were simulated and the main factors affecting sedimentation are studied. The sedimentation processes in the channel during 1997-2000 were simulated with the model. The processes and the deposit volume are in good agreement with field data. The simulated deposit volume included the deposit caused by horizontal circulation near the mouth areas and the deposit caused by density flow in the channel. The simulation reveals that most deposition occurs in the flood period when the concentration is relatively high, the deposition caused by horizontal circulation near the mouth areas is less than 20% of the total and the deposit caused by density flow is more than 80% of the total. The simulation also reveals that sedimentation in the channel is almost in linear correlation with the water depth and sediment concentration.

关键词： Numerical simulation Sediment deposition navigation channel Three Gorges Project

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

中国海洋工程:英文版 2023年第4期37卷 533-546页

作者： WANG Xiao-guang ZHANG Wei TONG Chao-feng LEI Zhi-yi QIN Jie JI Xiao-mei HUANG Rui The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

Deltas are densely populated industrialized regions,and home to important ports and navigation channels.Due to human interferences,the Yangtze Estuary has experienced a significant reduction in sediment load caused by the Three Gorges Dam(TGD),as well as adjustment to local morphodynamics by the Deep-water navigation channel(DNC).While the dramatic reduction in sediment triggers the increased channel erosion,the deposition flux of the DNC located at the estuary mouth has little change.To explore the physical mechanism of this phenomenon,a two-dimensional model is used to establish the relationship between sediment load and the sediment budget of channels based on the bathymetry in 2016.Model results show that the tidal reach and the inner estuary have a negative sediment budget.And the seasonal characteristics of water and sediment fluxes become less obvious downstream.Sensitivity analysis shows that the influence of upstream sediment load on deposition flux decreases along the channel,with a transition from deposition to erosion occurring in the tidal reach.For the last-level bifurcation,the annual siltation of sediment in the North Passage(NP)decreases by 4.5%with low sensitivity.This is attributed to the reduction of sediment load partially mitigated by riverbed erosion and cascade bifurcations.In addition,the lateral sediment supply,which accounts for 68%of the sediment input in the NP,is stable.Overall,this study strengthens the understanding of the relationship between sediment load and artificially deepened systems,thus allowing for better management of estuarine sediment and navigation channel.

关键词： delta navigation channel sediment load erosion and deposition sediment budget Yangtze Estuary

Responses of river bed evolution to flow-sediment process changes after Three Gorges Project in middle Yangtze River:A case study of Yaojian reach

在线全文

学校读者我要写书评

暂无评论

Water Science and Engineering 2020年第2期13卷 124-135页

作者： Li-qin Zuo Yong-jun Lu Huai-xiang Liu Fang-fang Ren Yuan-yuan Sun State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China Middle Changjiang River Survey Bureau of Hydrology and Water Resources Wuhan 430010China

The Three Gorges Project(TGP)has changed the flow-sediment process in the middle Yangtze River.For navigation purposes,there is an urgent need to study the changes of the river regime over a long-term period and the shoal-channel evolution over different seasons since the completion of the TGP.Based on analysis of the measured data and the results of a two-dimensional mathematical model,the changes of the river regime and river bed evolution in the Yaojian reach downstream of the TGP were studied.Results show that a high sediment transport flux helps to keep the main flow in the North Branch,while a low sediment transport flux helps to keep the main flow in the South Branch.Thus,the main branch will not change in the near future because of the low sediment transport load.In this study,the flow-sediment process adjusted by the TGP was restored to the conditions before the TGP,and the river bed evolution under the adjusted and non-adjusted flow-sediment conditions was calculated.After the completion of the TGP,the reservoir storage accelerated the flood recession process and decreased the erosion by 11.9%under the flow-sediment conditions in 2010,and the deposition in the flood season decreased by 56.4%.

关键词： River regime River bed evolution Flow-sediment process Three Gorges Project Yaojian reach Middle Yangtze River navigation channel

Siltation Prediction for navigation channels and Harbour Basins on Muddy Beach

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 1992年第2期7卷 157-172页

作者： Liu Jiaju Zhang Jingchao Prof. Senior Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, Nanjing Senior Engineer, River and Harbour Department, Nanjing Hydralulic Research Institute, Nanjing

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.

关键词： navigation channel harbour basin sediment concentration muddy beach sandy beach sedimentation prediction settling velocity flocculated granule

SEDIMENT MODEL EXPERIMENT IN JINGHONG HYDROPOWER PROJECT AREA

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 1997年第3期 301-307页

作者： TAN Guangming, Pro. and Doc. Wuhan University of Hydraulic and electric Engineering, Wuhan 430072, China ZHANG Xiaofeng Pro. and Doc. Wuhan University of Hydraulic and electric Engineering, Wuhan 430072, China DUAN Wenzhong Pro. Wuhan University of Hyd

An undistorted physical model is built to simulate the hindrance problem from flow conditions, sediment deposition in the navigation channel and in front of the dam for Jinghong hydropower project, Yunnan province, China. The requirements of similarity theory to simulate extreme fine suspended load were met through comprehensive investigation of the coal powder from Shanxi province. The material is very hard and has a stable chemistry property with median diameter of 0.006 -0.013mm adopted as model sand. Experimental results show that the model is successful in the simulation.

关键词： Model Experiment Project area Dam navigation channel

Investigation on the Deposition in an Excavated Trough at the East Shore of Jiaozhou Bay, China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 1995年第3期10卷 311-324页

作者： Zhang Jinshan Yu Guohua Research Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, Nanjing 210024 Research Senior Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, Nanjing 210024

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.

关键词： Jiaozhou Bay harbour basin navigation channel excavated trough sediment concentration muddy beach deposition tidal current numerical model.