The paper aims to study the dynamic squat model and safety speed control model of very large ship in restricted waters, so as to ensure the safety of navigation. The three-dimensional safety speed control model of very large ship is constructed in this paper based on the demand of channel width, vessel traffic flow characteristics and water depth. The reduced-scale ship experiment is conducted to measure the change of squat based on speed and water depth to draft ratio, and D-GPS full-scale ship experiment is carried out to verify and analyze speed standard model of very large ship. The experimental results have demonstrated the effectiveness of our proposed model.
With the rapid development of upsizing, high speed and specialization of ships, the navigation safety (Tian et al., 2016) has gained increasing attention in the fields of maritime management and ocean engineering, especially for very large ship in restricted waters. Very large ships can save cost and create more profits for the carrier, and also meet the demands of the global energy saving and environmental protection, so as to adapt to the fierce competition in the market (Liu and Liu, 2016). When the number of very large ships sailing in coastal waters is increasing, the probability and risk of ship accidents become relatively high. The enormous threat and loss of life and property caused by the maritime traffic accidents are becoming more and more serious, the ferry Herald of Free Enterprise accidentally capsized 1 mile out of the port of Zeebrugge on Friday 6th March 1987, which caused nearly 200 people died (Joseph et al., 1991). The accident investigation results shown that the ship sailing in shallow waters with high speed, and the ship sinking caused the bow wave into the forepeak, then sea water submerged the deck, resulting in the disappearance of stability and capsized (Dand, 1989). As a kind of navigation state in the restricted waters, shallow water navigation has its unique navigation law, such as the speed and the rudder force reduction, etc.
