Container terminals have become increasingly important within the worldwide trade and exchange of goods. As presently approximately 90 % of all general cargo on all long haulage distances is exchanged between producer and receiver by means of containers, container terminals play an important role for all time schedules set for global trade lanes.rn
rnScheduled container services between major ports are based on weekly calls for each service and line thus resulting in a tremendous pressure on the service times of container terminals. Downtime leads to financial consequences for the terminal and possibly for the port. This particularly applies to downtime caused by external factors, i.e. related to elements that cannot be controlled directly by the terminal operator, which include excess motions of moored vessels due to environmental conditions. Therefore, predictions of downtimes of container terminals due to wave and wind conditions form an important part of a new port design and operational studies. Port designers are faced with a number of choices, each involving careful economic considerations to arrive at a facility that matches the expectations of the owner and the operator. One important element of concern is the degree of protection from external factors needed for the (un)loading process to be efficient.rn
rnThe capacity of present-day container vessels is almost fourfold that of the standard vessels of the 90s. These larger vessels need relatively large manoeuvring areas for safe and continuous operations, which means that new ports often have to be built in exposed and/or extreme locations due to draft and length restrictions related to modern container vessels. This makes a detailed evaluation of downtime due to environmental conditions (waves, wind) even more critical.rn
rnVerifying the suitability of a new port design, or a planned extension of an existing port, requires that proper criteria are available. To facilitate this, PIANC has published a report on ‘Criteria for Movements of Moored Ships in Harbours’ [PIANC, 1995]. This was the result of the work undertaken by PIANC Working Group (WG) 24. Those guidelines covered several types of vessels, such as container vessels, general cargo vessels and bulk carriers. Some years ago, PIANC identified that particularly the criteria for container vessels required renewed evaluation in view of the developments in container vessel sizes during the last two decades and the trends seen in more exposed ports mentioned above, combined with an increased emphasis on efficiency and handling speed in the container transport industry.rn
