This historic Grade II listed building is being redeveloped to provide retail units at street level, office space at first floor and 15 luxury residential apartments.
The building is characterised by its heritage listed façade which will be retained. Mitchellson were contracted by Sir Robert McAlpine to provide bulk excavation, basement construction works, associated temporary works and drainage works for the project.
Our scope of work included the construction of a Perimeter capping beam in close proximity to neighbouring buildings and Bulk dig down to two basements with Temporary props installed as the excavation progressed below the capping beam. Due to the close proximity of the neighbouring buildings and a possibility of them settling/moving, a second set of props (Hydraulic) were kept on standby off site. If there was 2.5mm movement from the daily site monitoring of the capping beam then these props would require installing. The Temporary props were removed once the new basement 1 & basement 2 slabs were completed.
The challenge for Mitchellson at the Basement 2 stage of the project was dealing with an underground river running through the site as every tenth secant pile was kept short. The Basement raft was waterproof with Grace Membrane and waterproof concrete. Mitchellson worked together and were proactive in overcoming this challenge. Sir Robert McAlpine were also nominated for a temporary works award in respect of their design which was installed by Mitchellson.
The superstructure works for the project comprised of traditional Cores, walls & columns supporting in-situ slabs. Anti-Vibration/Sound bearings were installed under the Lift pits in the basement and on top of all columns at first floor. The Bearings were designed in New York and Manufactured in Thailand. The Façade was tied into the concrete structure using Anti Vibration brackets from Thailand. The installation and programme for the Anti-Sound/Vibration Bearings was very complex but satisfying.
Throughout the project Mitchellson ensured that the historical features of the building were preserved and the project was delivered on time and to the satisfaction of our client.
Extensive Temporary Works
Waterproof Basement Construction
Insitu Slab Construction
Traditional Core Construction