Project details
Neptune Yard is one of the UK’s leading CORE (Centre of Offshore Renewable Engineering) sites. Owned and operated by Shepherd Offshore, the site includes a 218m by 32m dry dock facility, one of the last remaining features from the regions proud ship building heritage. As part of investment plans to upgrade the site, a decision was taken to convert the dry dock into a test tank facility, which upon completion will be one of the largest in Europe. Whilst a large proportion of the dock will be subject to infill, a section at the entrance will be left so that it can be filled with water to test bespoke equipment associated with the subsea and offshore engineering industries. As part of this development, Southbay were awarded a contract to construct 2no. Reinforced Concrete Retaining walls.
Initial works included the removal of existing marine growth from the dock walls. This allowed the construction of both the front and mid retaining walls to commence in the form of dowelling and casting of shear keys to the dock floor. In total there were 8no. concrete pours to form the wall at the front of the dock entrance, and 7no. pours to form the wall across the
middle section of the dock. Each pour was constructed using the same methodology, with scaffolding access first erected, prior to cleaning the base of the previous pour. A hydrophilic strip was then installed which allowed for the erection of temporary formwork. Dowels were then installed in preparation for the pouring of concrete. Once poured, the concrete was provided with the required finish and approved by the onsite Engineer. In constructing both walls, multiple concrete pours of up to 600m3 were required, all within a restricted site environment. When constructing the retaining wall across the middle of the dock, drainage
was provided at either end of the structure which involved the installation of flap valves. Following the construction of both walls, a top slab and parapet were installed to complete the structures.
An excellent standard of safety was maintained throughout the project, with a significant interface existing between the Southbay, and G’Obrien project team. Frequent, planned communication between both contractors and careful programming of the works ensured all risks were successfully controlled. Further considerations included working within a confined site environment. This included monitoring air quality within the dock, and monitoring water ingress at the dock gates. In addition to the provision of perimeter handrailing, additional staircases were installed to provide increased access.
