详情

原文传递 Minimum Safe Underkeel Clearance in Port Entrance Channels

题名：	Minimum Safe Underkeel Clearance in Port Entrance Channels
作者：	J MOES; M ROSSOUW; Capt M BROPHY; F VAN LOON
关键词：	Underkeel Clearance ; Port Entrance Channels
摘要：	Due to developments in shipping, ports are under continuous pressure to accommodate wider and deeper-draught ships. Dredging of the entrance channel provides a solution, but this is an expensive option. The challenge, therefore, is to find the maximum safe draught of a particular type of ship for an existing port entrance channel as a function of the tide, wave conditions and ship speed. For the development of a new port, the minimum safe depth for the “design” ships visiting the port has to be determined, with an acceptable percentage downtime. In both cases, the accurate statistical determination of wave-induced vertical ship motions is usually a critical component for entrance channels exposed to wave action. Because of the dependency of the maximum allowable ship draught on the environmental conditions, these have to be monitored, and preferably be predicted, with an acceptable degree of completeness and accuracy. In addition, the marine staff at the ports needs an adequate decision support system to allow them to take ship allowance decisions based on proper and reliable data. Such port operational decision support systems can now be developed based on modern computer technology, ocean monitoring and forecast models and in-depth knowledge of ship behaviour in waves. This paper presents a description of ship allowance decision support system, in operation at the Port of Richards Bay, South Africa. This system is partially based on small-scale and numerical model tests, which were verified by local measurements of ship motions with simultaneous recording of tide, wave and ship conditions. The measured wave parameters include the wave height, period and direction. Based on these relationships, the maximum safe draught for Richards Bay can be determined as a function of tide, waves, ship size and ship speed. This is implemented in the PCbased DMAX system.
总页数：	Proceedings of the 30th PIANC-AIPCN Congress. Sydney Australia. 22-26 Sept. 2002. pp8
报告类型：	科技报告