Canary Wharf’s new district; Wood Wharf, has been designed to provide a new waterside community, defined by the quality of its public spaces and the diversity of its land uses.
Laing O’ Rourke were tasked with creating a concrete foundation slab to be positioned on steel encased reinforced concrete tubular piles that would sit above the water level of the Thames upon which several of the main towers involved in the development would be built.
As part of the foundation the following tubular pile lengths were urgently required; 124 tubular piles 1219 mm O/Dia x 10 mm Wt. x 17-18 m long
Having competitively tendered and won the contract to supply, Cleveland Steel & Tubes Ltd(CST) set about reserving the suitable quality and quantity of mother pipe from its own stock and, using its own in-house certified facilities, started to fabricate the long lengths required.
Reinforced bayonet collars were required on the top of each casing, enabling the casing to be twisted into the ground. The collar is normally 40 mm thick, which would usually require a specialist rolling, which for these large diameter casings means expense and time.
A specific request was made of CST by the Project Construction Manager to come up with another design for the collar, leading to a suggestion that a 500 mm long piece of 1219 mm O/Dia x 17.5 mm Wt. mother pipe could be cut into sections (arcs) and welded around the top of the casing.
This option was indeed taken up by the project and meant a good Cost Effective Value Engineering Solution could be implemented showing a 50% saving when compared to the 40 mm thick collar.
The project did suffer various delays due to issues on site and it was a challenge to keep stopping and restarting production to keep a steady flow of casing to achieve the exacting delivery requirements.