Liverpool Metropolitan Cathedral
Project overview
One of the largest catholic cathedrals in the UK – Liverpool Metropolitan Cathedral – is undergoing a transformation of the existing Piazza Café building at the base of the cathedral’s main entrance.
The Piazza Café forms part of the existing sloped garden area. A new retaining wall was required to enable the rear of the existing café building to be exposed and a new courtyard area to be created for the future redevelopment.
Technik Ground Solutions Ltd was selected to be part of the construction team at an early stage to assist in the development of the retaining structure.
The project
The works were to take place in the garden area of the iconic cathedral. The main contractor carried out the initial enabling works, which consisted of the removal of the existing fill material, formation of the working platform and, most importantly, the protection to the existing Susanna Heron ‘Still Point’ artwork contained in the gardens.
Works had to be carried out in a sensitive manner to ensure pre-arranged events were not disturbed in any way. The cathedral itself was still open to the public, and visits, tours and trips continued alongside the normal busy schedule of a cathedral.
Solutions provided
Originally, a sheet piled wall was envisaged for this project; however, the scale of the site, including working around the existing monument, and the shallow bedrock meant that the use of the rig required to successfully install sheet piles of this scale would have been impractical.
We designed a 450-mm-diameter contiguous piled wall for retained heights that ranged from just over 1 m to almost 4 m. We understood in advance that the fill material present may be problematic but not to what extent. Our powerful restricted access Hütte 205 rig was engaged to install the piles, as it provided the best possible chance to overcome the obstructions encountered with its relatively small footprint and enormous capability.
Piles were socketed into the underlying yellow sandstone and proved no match for the torque of our rig; 94 piles were installed in total, 13 of which were bearing piles for the foundations to a raised walkway.
The works progressed extremely well, with excellent communication and a proactive team-based focus on the project by the architect, main contractor, engineer and groundworkers involved. Technik Ground Solutions is privileged to have worked on such a well-known landmark of the Liverpool skyline.