The Port of Southampton is the UK’s biggest exporting port. Over 950,000 cars pass through the port each year, a third of which arrive by rail, with 60% going for export. Associated British Ports (ABP), the Port’s owner, has become a pioneer in using multi-deck car storage facilities to make more efficient use of available space, which is at a premium in Southampton. With an ever increasing demand for car storage, ABP is proposing to build an 8th multi-deck car storage facility at the Port in the Western Docks.
The Western Docks were constructed in the 1930s. Previous site investigations by REC have shown the land to be built on up to three metres of made ground, overlying natural tidal flat and river terrace deposits, and the ‘Selsey Sand [geological] Formation’. It was, therefore, important for ABP’s engineers to have the ground conditions accurately defined in order to design foundations to cope with the loading of the new multi-deck.
REC was commissioned by ABP to undertake the detailed Ground Investigation and Assessment at the proposed multi-deck site. In order to accurately establish the deeper geology at the site into which the foundations are to sit, REC’s local office in Winchester has drilled five boreholes to 30 metres depth using a cable percussive method, which can cope with man-made obstructions in the made ground. REC utilised three ‘strings’ of drilling casing (250mm, 200mm and 150mm with bentonite seals at each reduction) in order to ensure that the target depth of each borehole was reached and to prevent any potential for downward migration of contaminants into the groundwater below. The mechanical strength of the shallower soils was also determined by excavating six shallow test pits and conducting bearing pressure tests.
Having completed the ground investigation, REC is providing ABP with a comprehensive ground investigation report that will be used to inform prospective contractors tendering to build the multi-deck of the ground conditions and enable them to accurately design and cost the necessary foundations. This should remove the need for contingency sums and provide ABP with a more cost-effective price from its contractors, saving ABP money in the long run.
Regional Director for REC, Stuart Philips, says of the work: ‘REC’s site investigation for the multi-deck storage facility will enable ABP to further meet the demands of ever increasing numbers of cars passing through the port and in turn, contribute to Southampton’s overall position as a leading logistics provider in the automotive industry in the UK. As a locally based business, we’re thrilled to continue to be part of that evolution.’
Connor Smith, Project Engineer for Associated British Ports, commented, ‘Over the last few years, the demand for car storage at Southampton’s port has increased significantly – and Associated British Ports are committed to meeting such requirements by establishing cost-effective and efficient, large capacity solutions, such as the proposed new 8th multi-deck storage facility in the port’s Western Docks. Ground Investigations are a crucial part of the foundation design process, so we are happy to have REC’s expertise on board to provide us with this important information early in the project process’.