Awkward access and a lack of accurate records made it difficult to identify the boat deck’s composition. Modern laser scanning techniques helped determine the existing geometry. The central core of the pier is its grid of Victorian-era cast iron screw piles. In the mid 1990s the pier head had been extended and the new structure surrounded the original. Adding to the challenge, Horatio’s Bar, which sits over the boat deck, was in good condition and was to remain open throughout works.
3D modelling was used to identify an efficient solution that would enable operational continuity. A temporary platform was erected under the pier from which work was carried out, allowing the old structure to remain in place and minimising weather risks.
Twenty-four steel helical screw piles were assembled from short lengths and scour protection was provided in the form of concrete jackets. The piles are braced by an assembly of new beams above them as replacement support for the deck and building.
A replacement beer store clad in precast concrete panels was also built, supported by new steelwork. Following installation of the new structure, the old boat deck was carefully dismantled and removed from site.
Brighton Pier is a Grade II* listed building which opened in 1899. The pier head comprises structure from three distinct periods. The central core is constructed of Victorian cast iron screw piles while to the northeast corner is an area approximately 35m x 15m known as the boat deck and built in the 1930s. In the mid-1990s, the pier head was then extended, with a new structure surrounding the original construction. A recent condition survey showed that the boat deck structure was in poor condition and would have to be replaced. Ramboll was employed to design a sympathetic replacement scheme.
We devised an innovative approach to replacement works with the old structure still in place, while also keeping the pier’s bar operational and minimising weather risks. This involved erecting a temporary working platform under the pier. From here 24 new steel piles were assembled from short lengths, and then braced by an assembly of new beams above them as replacement support for the deck and building.
Before starting this work we needed to identify the boat deck’s composition; a task made problematic by the lack of accurate records and difficult access. Our surveyors therefore employed laser scanning techniques to determine its existing geometry. We then used our pioneering Laser Aided Modelling® process to produce a 3D spatial model of the pier’s main substructure, followed by an outline and detailed structural design. In advance of any survey work taking place, a risk assessment, which included consideration of the exposed environment, was undertaken.
