With the recent globalization of world economy, the amount of world trade continues to increase. Specifically, container transportation becomes more important due to its speed and safety. Container ships of more than 110,000DWT were completed and went into service last year. Container vessels with improved speed / higher mileage capacity has very short parallel hull. It is very difficult for the pilot to maneuver the latest container safely. There are more berthing accidents at container berths than oil and LNG berths. The accidents are possibly due to approach velocity, berthing angle and ship size. Ueda and et al presented the statistical design method of fender systems at the 11th and 12th ISOPE. In this paper, the analysis will be made to obtain the probability of failure and the safety factor following the method proposed by Ueda and et al, with observed data of approach velocity and ship size at the existing berths. The authors discussed and explained the meaning of safety factor and/or abnormal berthing factor described in the British Standard and PIANC WG33 Report 2002 and thereafter it was compared with the conventional design method.
The function of fenders is to absorb the kinetic energy of berthing vessels and to reduce the impact force between vessel hull and quay wall. The energy absorption of fenders has to be larger than the berthing energy. In addition, it is recommended to consider the safety factor and /or abnormal factor in the British Standard and PIANC WG33 Report 2002. The authors collected vessel approach velocities their corresponding vessel size at some major container berths in Japan and Malaysia. Also, the berthing angles were measured. However, the measured angles were smaller than the design condition. When the berthing angle is large, the flare angle and fender angular compression performance should be considered in the fender design.
