Cementation Foundations Skanska is packing up after successfully completing the country’s largest foundations contract, a 2.5 km diaphragm wall up to 31 metres deep for CTRL contract 230, known as the Stratford Box.
Construction of the retaining wall for the one kilometre long below-ground structure to house Stratford International Station, where Skanska is the main contractor, took 15 months and involved 250 people, 90,000 m3 of concrete and 12,000 tonnes of steel.
Cementation Foundations Skanska, supported by its fabrication and plant maintenance facility at Bentley, Doncaster, deployed an array of modern diaphragm walling equipment, including three hydromill cutters, seven hydraulic grabs and 26 handling cranes – all adapted for the purpose by its team of skilled engineers.
Peak production of the 1.2m and 1.5m thick wall reached over 3000 m2 of diaphragm wall excavated per week.
Working on a busy site, control of logistics was vital with management of people, plant and materials needing careful planning. We also planned and implemented safe systems for working next to a live railway and under high-voltage power lines.
Project manager Ken Ryder said, “We are probably the only foundations specialist in the UK with the resources to do a contract of this size on our own. Our work has been helped by our close relationship with our colleagues at Skanska, project manager Rail Link Engineering and client Union Railways North.”