Careys Civil Engineering was principal contractor on the substructure for Merchant Square, located in the Paddington Basin. Our works entailed the construction of a 12m deep secant piled basement which adjoined two existing developments at 4 and 5 Merchant Square, and included an element of sheet piling to accommodate future development. After winning this contract, we were also contracted to undertake superstructure works on the project, consisting of two towers of 18 and 21 storeys in height.
To enable us to progress our excavation works as quickly as possible, we installed 47 metre long props that measured 1.2m in diameter, spanning the entire basement at ground floor level. Our concrete works in the basement were finished to a high specification with all exposed concrete columns being left as struck with no making good permitted by our client.
The project was constructed over the London Underground Bakerloo Line and the southern element of the basement was only 500mm for the fragile, 100-year old brick wall of the Paddington Canal. To safeguard these elements, our team undertook regular planning and liaison meetings with Transport for London and British Waterways.
As the basement adjoined two neighbouring developments, construction of one of the two superstructures was undertaken within 500mm of 4 Merchant Square. As the core in the western tower was of a larger, irregular shape, we elected to use Doka’s self-climbing formwork system to complete one floor every three days.