![]() The Panama Canal, accompanied by two sets of locks on the Pacific and Caribbean sides of the Panamanian isthmus, connecting the Atlantic with the Pacific, is a well-known example. The historical growth in container vessel sizes is largely defined by the size of the most important canals and locks. Two decades later, cellular container ships were developed, committing exclusively to container transport. The first vessels sailed in the 1950s, often being general cargo vessels with containers stowed on board. Container fleet 2.1 HistoryĬontainer shipping is a relatively new mode of sea transportation. As passing distance and velocity are often fixed due to channel restrictions and minimal manoeuvrability needs, mitigating measures, improving the safety of the moored ship at the quay wall, are presented. The behaviour of the moored ship is calculated in the time domain using UGent’s in-house tool Vlugmoor. The passing ship effect is simulated using potential software RoPES. A case study, based on study work for the Port of Antwerp (Belgium), is presented, where the behaviour of the moored vessel is simulated numerically for varying passing distance and speed. A set of ship longitudinal (surge) motion criteria is developed based on literature and the in-house experience of Ghent University. The safety of the moored vessel is discussed extensively in the light of external load type and by looking at the container (un)loading process in detail. The passing vessel effect is discussed in general, citing relevant literature where the hydrodynamics are discussed in detail. It is thus needed to assess these effects on moored ships, which is the topic of the current paper. The larger displacement of the vessels adds to the passing force increment. The passing distance, side-to-side, decreases with increasing ship width. With more, larger container ships visiting ports, the number of potentially critical passages increases. Many ports are faced, however, with limited expansion possibilities, as land becomes scarce, being a trade-off between industrial, demographic and ecological needs. Dredging works, combined with terminal renovation, or even development of new quay infrastructure, allow good accessibility of the port. While ports and quays (civil works) are destined to past 100 years or more, ships only have projected lifetimes of 20 years, allowing the ship sizes to grow much faster than port and quay infrastructure. This puts pressure on ports, as they need to keep up with the growth in ship size. Ports and container terminals thus need to handle these sea giants on a daily basis. Nowadays, the general cargo fleet consists of small ships ( 12,000TEU), which nowadays account for 18 per cent of the total container capacity ( SEA Europe, 2017). These general cargo ships had the leading share in worldwide transport for decades, but have been largely replaced by container vessels. When focussing on cargo vessels, five main types are identified: container vessels, bulk carriers, tankers, RoRo’s and general cargo vessels. Nowadays, the seaborne trade accounts for 90 per cent of the worldwide trade ( QinetiQ, Lloyd’s Register and Strathclyde University, 2013). The shipping industry forms an indispensable link in the global market chain. = Non-dimensional representation of x p (–).
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