Designing new quays and ferry slips
Since the 1970s, Aas-Jakobsen has been designing a varying range of quay types, including ferry slips, which are a special type of quay that are described below. Some of the more traditional concrete quays include the deep-water quays in Florø and Tyssedal, as well as quays for the Tofte Cellulose Plant on both sides of the Oslofjord. Sheet pile quays include the sheet pile quay at Kneppeskjær in the Port of Oslo. Aas-Jakobsen has been working with concrete in the marine environment for more than 60 years, and we have been an active contributor to the Norwegian Concrete Society’s publication no 5 ‘Design and execution of concrete structures in water’.
Aas-Jakobsen was one of the first companies to start using concrete elements in quay construction, and in the 1980s was secretary for the Norwegian Concrete Society’s publication no 17 ‘Guidelines for the use of prefabricated concrete elements in the construction of quays and ports’. The ro-ro quay at Kneppeskjær for the Port of Oslo was designed and constructed with large concrete elements and assembled using a floating crane. Lavik Quay was designed and constructed with small deck elements, more in line with the NCS’s publication no 17.
Some of our more prominent special quay projects include Aker Brygge and Tjuvholmen – these are urban districts which have been completely or partially built on or within quay areas. Tjuvholmen in particular is of interest because it rests on a foundation of a relatively small number of large, prefabricated submerged caissons which are lowered onto drilled piles and supported partly by the buoyancy of the water. The quay fronts in these districts are suitable for recreational vessels.
Ferry slips are covered by the same regulations as bridges, but are inherently different, because they act as transition structures between land and sea, which means that they are subject to impacts and drag from ferries, and they have mechanical, electrical and hydraulic components. Designing ferry slips properly therefore requires detailed knowledge of the structure type and insight into a wide range of related disciplines.
Since 2009, Aas-Jakobsen has been part of many projects involving the design of new slips, and the renovation, inspection and verification of existing ferry slips in Norway. We have also been closely involved with the Norwegian Public Roads Administration’s development of new Norwegian regulations and new standardised ferry slip bridges. Because of higher traffic volumes, bigger ferries and an increasing focus on environmental considerations, this has been a period of rapid development for the ferry slips in Norway. Ferry slips have become bigger and it is now much more common for them to be fitted with automatic mooring systems and charging systems for battery-powered ferries. Aas-Jakobsen has been one of the leading companies in Norway in these developments.