Precast Concrete
Aarsleff Goes To Ikea
Aarsleff Piling, peppered the backfilled clay pits at a former brickworks at Fletton, on the outskirts of Peterborough, with about 6,500 of its precast concrete piles, which supported the floor slab and warehouse for a huge new £32M distribution centre for the Swedish household goods retailer IKEA.
Shepherd Construction was the main design and build contractor for the IKEA project and followeding pre-contract test piling and probing on the site awarded the approximate £1.5M pile supply and installation subcontract to Aarsleff Piling.
We endeavour to work as closely as possible with our clients at the tender stage and when we think it will be beneficial we also carry out trial piling and probing to assist in designing the optimum foundation layout. For the IKEA project the strategy was especially beneficial, as the foundation design played a major contribution towards Shepherd winning the overall design and build contract.
Aarsleff and Shepherd’s worked together on the pile design to achieve the best value solution and most economical pile and slab design. Shepherd’s were please to have a dependable piling contractor who were geared up to supply and install piles at a quick rate. Aarsleff has the ability to feed the process in-house, make the piles, and install them, this is a big advantage. An initial stock of piles on site when the project first started meant that once the project was up and running it moved onto a just in time basis, that worked very well. Shepherd Construction were very pleased with the piling operation, which was always ahead or on programme.
Aarsleff had to make and drive the 250mm and 300mm square section precast concrete piles, predominantly in singles, on a 4.3m grid, through up to 14m of pulverised fuel ash backfill to toe into the underlying stiff clay. The former brickwork’s clay pits and lagoons had been backfilled with the PFA, which Shepherd Construction had stabilised with lime and cement in 300mm thick layers to provide a very clean and strong working platform for the vast site.
Aarsleff started the 17–week project initially with three Banut self-erecting hydraulic drop hammer fixed leader rigs. But progress was so fast Aarsleff cut back to two rigs and averaged about 90 piles/day. Peak daily production reached 140 precast concrete piles. The two Banut rigs were also temporarily supplemented by the company’s largest Hitachi KH180.3 GLSK fixed leader rig, prior to its move to an 18-month contract on the Channel Tunnel Rail Link.
The precast concrete piles for Shepherd’s IKEA distribution warehouse were made at Aarsleff Piling’s wholly owned subsidiary Centrum Pile based at the company’s Newark, Nottinghamshire headquarters. Centrum Pile focused purely on the manufacture of continuously reinforced precast concrete piles at the modern factory, which has been extended to boost production capacity by a further 60%. The company, which has invested extensively in new concrete batching, transfer and mould filling equipment and fully robotic pile cage fabrication, is believed to be the UK’s largest manufacturer of fully reinforced precast concrete piles. Peak production, using the special free flowing, self-compacting concrete, has reached a record 16,500 linear metres/week
