Content area
Full text
A clear tendency of moving from prescriptive to performance based safety regulations is emerging internationally. Introduction of performance standards is seen as beneficial to industry, allowing consideration of alternative designs as well as a rapid implementation of technological innovation. In this respect, the analysis of alternative design solutions, particularly in the case of Ro-Ro ferries, requires the development of a standardized approach to demonstrate compliance with the requirements of intact and damage stability regulations by a combination of physical model experiments and numerical model tests while applying probabilistic techniques in the process of assessing damage survivability. The procedure pertaining to model experiments is described in the SOLAS Regulation II-1/8 and the "Interim Guidance Notes for a Uniform Model Test Procedure" relating to this regulation. This paper concentrates on the development and validation of a mathematical model to be used for numerical model testing and the proposal of rational survival criteria allowing for a probabilistic assessment of the dynamic stability of damaged ships, in a way that could not be simpler for practical applications
INTRODUCTION
The limited understanding of the complex dynamic behaviour of a damaged vessel and the progression of floodwater through the ship in a random sea state has, to date, resulted in approaches for assessing the damage survivability of ships that rely mainly on hydrostatic properties with potentially serious consequences concerning the loss of life and property and danger to the environment. One only too well known example and the focus of this presentation concerns the serious flooding of ships with large undivided deck spaces, such as rollon/roll-off vessels, where the loss could be catastrophic as a result of rapid capsize, rendering evacuation of passengers and crew impractical, with disastrous (unacceptable) consequences. Concerted action to address the water-on-deck problem in the wake of the tragic accidents of the Herald of Free Enterprise and more recently of Estonia led to the proposal of new stability requirements, known as the Stockholm Regional Agreement, or more commonly as SOLAS '90+50, pertaining to compliance of existing Ro-Ro vessels with SOLAS '90 requirements while accounting for the presence of a maximum 0.5 m height of water on the vehicle deck. The dates of compliance with the provisions of the agreement range from April 1, 1997 to October...