Constructing a parking garage underneath historical city canals - a case study

Abstract

Typical Dutch historical city centres are characterised by the presence of canals. Due to increasing demands on public space, these canals make promising locations for the construction of large underground spaces, such as parking garages. There are no significant buildings overhead and they are often situated close to their target users. My graduation project covers a feasibility study on a parking garage underneath the Geldersekade canal, in the centre of Amsterdam. Apart from integration into the historical appearance of the canal, the risk of damage to adjacent buildings, caused by soil deformations during construction of the garage, is of great influence on the design. A construction method is investigated that puts the qualities of the surrounding navigable water to good use in an attempt to reduce the adverse effects of the construction process, especially when compared to traditional methods. Prefabricated immersible elements are applied to form a dry construction platform in the canal. On top of this platform a caisson is constructed and subsequently immersed into the ground by means of the so-called ‘pneumatic caisson’ method. The entire garage is made by construction, immersion and interconnection of several of such caissons. Although slightly more expensive than traditional construction methods, the elaborated concept turns out to be very promising in an urban environment. The absence of a dry cofferdam is a significant advantage over traditional bottom-up methods, especially regarding soil deformations and the risk of leaking retaining walls.