Study On The Methods To Determine Navigation Planar Dimensions Under Limited Water Areas

Waterway transport is an important part of a comprehensive modern transportation system. The infrastructure including seaports and channel is a key stimulus for trade, economic and social development in China. In the past 10 years, when construction of China's port has stepped into a new round of high tide, the trend of larger and more professional ships and the rising size of the main harbors for oil or chemical tankers, container ships or bulk cargo ships have greatly improved the standard of harbor infrastructure. To determine the planar dimensions of the seaport waters, including channel width and planar scale of turning basin for ships sailing in waters, and to ensure reliable navigation and security have become closely related with the national economic development and the construction of national defense.For half a century, scholars have carried out some research on determining channel width and planar dimensions of turning basin. Especially the governments in developed countries and PIANC, with the help of related research, have developed a series of standards and manuals for fairway design. However, the issue of channel width and planar dimensions of turning basin is so complicated that this problem remains to be further in-depth studied.This paper analyzes and compares the current domestic and international standards to determine the channel width and the planar scales of turning basin. The main factors affecting the planar dimensions of the track width, channel width and turning basin are summarized. Comparison between our national and foreign standards is conducted. Combined with an example of a port project in southern China, the planar dimensions are calculated based on various national standards, which verify the security of the preliminary design value scale of the harbor. Accordingly, this paper further analyzes advantages and disadvantages of the methods to determine the navigation planar dimensions based on our national current standard. It is shown that the method of calculating the channel width in the current Chinese regulations needs to be further revised. In order for this, suggestions are proposed for determination of channel width for straight channel and the junction of two straight channels and planar dimensions of turning basin before a new standard is formally issued. The suggested methods were proved by using an interactive, physics-based, PC real-time ship maneuvering simulator DynaSIM.This article also draws upon a ship navigation simulator—DynaSIM, introduced from the United States, to fulfill a comprehensive and realistic simulation of the navigation project for a liquid chemicals terminal in the Chinese southern port; Various design ships under the combined effects of different wind, wave and currents are simulated to navigate along the main channel, and to turn around and moor in the turning basin nearby the berths As a result, a scientific, reliable and operable method has been demonstrated to determine the ship required track width, and the planar dimensions of the turning basin, including the vertical and horizontal distance.The calculation results according to various national standards show that our planar dimensions based on our national norms and foreign standards are roughly equal. And the values of our national norm are slightly conservative when the channel width is determined in the unsatisfied circumstances (cross-wind or cross-flow is more severe than usual). Despite of the fact that more factors are considered to determine the planar scales of turning basin, the result is similar; Meanwhile, numerical simulation verifies the security of the navigation planar scales and demonstrate when the dangerous situation may occur; In addition, comparison between the results of theoretical calculation and numerical simulation verifies that the numerical simulation method based on DynaSIM is completely reliable and that to make the ship navigate within a relatively more narrow waterway or a smaller turning basin is totally feasible, even if the natural conditions are less favorable.