Background

The maritime industry requires fast, dependable and affordable vessels for surveillance duties, interception rescue operations and security operations like the combat against terrorism, drugs and piracy. These type of ships are also deployed as crew transport vessels for offshore platforms and pilot boats. The Dutch maritime industry, especially Damen Shipyards, are specialized in the design, development and building of those type of vessels in a standardized and modular fashion. Because of substantial reduction in installed power and by that, a substantial reduction in fuel consumption, and on the other hand also a good opportunity to recycle the hull of the vessel, these ship types are built in aluminium.

Operational experience shows that the aluminium structure of these ships show unexpected fatigue cracks after a few months of hard use. Once the nature of the problem of fatigue can be addressed in an early design stage, large cost benefits are expected for the building and maintenance of the vessels. Damen Shipyards also expects an increased volume of fast aluminium vessels to be delivered to the market. Insight in an early design stage of the fatigue behaviour of the design will result in an optimum structure with minimum weight for the ship. Also the reputation of the Netherlands shipbuilding industry of producing high quality durable products is not endangered.

Objective

This 4-year project (2008-2011) aims at the development of a practical and efficient methodology for the prediction of the fatigue life of fast aluminium vessels in an early design stage. The project is a cooperation between Delft University of Technology, research institutes (MARIN and TNO), class societies (Bureau Veritas and Lloyds Register) and a shipyard (Damen Shipyards Gorinchem).