Improvement of Mooring Configurations in Geraldton Harbour

Abstract

Ports exposed to high energy long wave conditions can experience significantly reduced berth operability. Geraldton is perhaps one of the best known examples. Recent studies to mitigate the problems have concentrated on the reduction of the long waves by extending the breakwater. However, this is quite costly. Various countermeasures related to the mooring configuration are defined and analysed in this paper. The analysed alternatives are use of shore-based mooring lines, installation of softer fenders, a combination of these two, and deployment of Cavotec MoorMaster™ units. These alternatives were compared with the existing mooring configuration and with the option to extend the breakwater. The best improvement (50% increase of threshold long wave height inside the harbour) is reached by installing a combination of pneumatic fenders and constant tension winches set to 30 t, or nylon breast lines on a brake winch with a pretension of 25 t. In this way, the vessel is pulled into the fenders and fender friction prevents excessive surging of the ship along the berth.

Keywords

• long waves
• moored ships
• port engineering