Research Of The Through Capacity And Traffic Organizational Model In Main Channel Of Large Sea Harbor

Anchorage, fairway and berth are the basic elements of port operation and water transport. On the basis of these elements, port scheduling scheme and safety management of port waters are put forward to. The entry fairway capacity (saturation) directly determines the organizational management of the port operation and the increase in the throughput of the port. The study of fairway capacity could be divided into two stages: firstly, study and analyze the current situation of the fairway capacity or evaluate the saturation in order to determine whether the fairway should be extended or it is necessary to take relevant management measures and optimize the scheduling scheme to improve the fairway capacity; secondly, according to the development of the port throughput, predict the ship traffic flow in port waters and the future fairway capacity so as to provide the support for the decision-making on future planning and construction scheme.Due to the development of larger, high-speed and specialized ships as well as the increasing water traffic volume, fairway capacity is influenced more obviously by the water depth, fairway direction, anchorage conditions and berth conditions, etc. Consequently, it results in much fairway congestion. Tianjin Port has the longest artificial fairway in China. Because its entry fairway capacity is constrained by its depth and width, lager ships are required to enter the port in one-way navigation or with appropriate tide. This has seriously hampered the development of the port. In recent years, the study on entry fairway capacity has been a concern of the relevant engineers, designers and researchers at home and abroad, however it is still rare. The majority of the studies regard non-port fairway as their object and fairway as a waterway in form of tunnel. Moreover, it is mainly from the general property of the fairway (length, width and depth, etc.) and the general attributes of ships navigating (speed, size and ship type, etc.) to study the fairway capacity, especially the static fairway capacity without consideration to the influence of the anchorage, berth, rule of ship arrival, port operation and management. So, it is suggested that the study on entry fairway capacity should focus on reflecting the dynamic nature of the port system as well as the fairway property and its service level, more importantly reflecting the characteristics of port system, rule of ship arrival, ship behavior and the form of port traffic organization.This dissertation aims at, from the system point of view, on the basis of studying the traffic flow patterns and fairway characteristics, with the fully analysis and consideration to the multi-constrained conditions of fairway capacity and ship behavior characteristics in port waters, revising the existing static calculation model (ship domain model) for fairway capacity, constructing the general static calculation model, establishing the dynamic calculation model for entry fairway capacity with the use of queuing theory according to statistics of historical data of ship arrival. In addition, make the simulation, verification and forecasting for entry fairway capacity and vessel traffic flow in port waters through computer modeling in order to study and identify the modes of traffic organization, which are suitable for the fairway capacity and its service level.The main research work of this dissertation includes:(1) This paper makes a clear definition and boundary for the main fairway capacity of large harbor and its navigation ability, discusses the relationship between fairway traffic capacity and the port system and the influential factors of fairway traffic capacity, does a comparative analysis on the related outcomes and points out the deficiency of the existing calculation models and methods.(2) According to the port characteristics, the behavioral characteristics of ships and the historical data of the ship traffic flow in the port waters, aiming at the problem of unchanged weight in the CSFM prediction methods, this paper builds up a serial of revised variable weight combined forecasting models, which are a better solution to the drawbacks of poor accuracy and dependence on the experience in the existing vessel traffic flow prediction algorithm.(3) This paper makes an argument and analysis on the theory and calculation methods of traffic capacity both at home and abroad, introduces some definitions about the domain of ship navigating, crossing and converging, on the basis of analyzing the characteristics of traffic flow in the entry fairway, fully takes into account the amended methods of the ship domain models in different modes of ship encountering and puts forward to the general calculation model for entry fairway capacity in multi-source converging conditions.(4) This paper establishes the dynamic calculation model for entry fairway capacity with the use of queuing theory according to the rule of ship arrival and the characteristics ship behavior, which has been verified and analyzed by the example of Tianjin Port.(5) On the basis of the above-mentioned studies, this paper takes the use of the basic academic theory of computer and system engineering, operations research, mathematical statistics and so on to develop the related simulation software in order to simulate and predict the fairway traffic capacity of large harbor.(6) This paper puts forward to the traffic organization modes of entry fairway according to different fairway traffic capacity and introduces the concept of fairway service level for the purpose of studying how to improve the fairway traffic capacity through optimizing the traffic organization modes.The main innovations in this dissertation are as follows:(1) To build up a macro combined forecasting model for vessel traffic flow in the fairway of large harbor, based on the characteristics of the port and the ship behavior.(2) To discuss and analyze the theory and calculation methods of traffic capacity both at home and abroad, construct the general static calculation model and method based on the ship domain theory with full consideration to different modes of ship encountering.(3) To establish the dynamic calculation model for entry fairway capacity with the use of queuing theory according to the rule of ship arrival and the characteristics ship behavior.(4) To built up the traffic flow organization model of the duplex-fairway in Tianjin Port based on the fairway traffic capacity (its service level) .Research work of this dissertation is at the forefront of transportation science and is also a hot point and a difficult problem, which many scholars are doing research on. The results of the research in this paper fill the gap in the national community and are at the forefront of the field. The application of research results can not only provide the technical support for the decision-making on future planning and design of entry fairway but also have the important theoretical value and practical significance for ensuring the safety of port operation, improving the comprehensive utilization of port resources, protecting a good navigation environment and order in port waters, maintaining the navigation safety in port waters and promoting the port sustainable development.