A POLYSTYRENE formwork system for ground beams and pile caps more normally associated with house building is producing significant benefits on a large retail contract in Leeds.
Main contractor Laing is using the latest incarnation of manufacturer and supplier Rom's Beamform Plus system to generate a tenfold reduction in shuttering installation times for a supermarket and retail complex in the Kirkstall Road area.
The project, on the site of a demolished print works, includes a 7,250m2 Morrisons supermarket, a 3,700m2 retail unit and three rugby pitches.
Structures are founded on about 500 long driven cast insitu piles between 6m and 13m.
Design meant that pile caps had to be constructed before the linking ground beams were cast.
Instead of taking two joiners three hours to build the timber formwork for a 6m long ground beam, Laing says it took only two hours to complete 24m of shuttering the first time it used the system.
As the formwork is permanent, it does not have to be removed after concreting, saving even more time. The firm calculated that to break even,3m of shuttering had to be installed per man hour. In fact, Laing construction manager Dave Firth says this can be achieved in only ten minutes. He adds that semi-skilled labour can be used, freeing up skilled joiners to work on other parts of the contract.
Rom says recent design improvements means that the 1m long and 120mm wide, heavy duty flame retardant polystyrene blocks are now available in 50mm high increments from 350mm to 750mm. Simple interlocking tongue and groove ends and 'easy to cut' blocks make installation quick and simple, it adds.
Reinforcement cages can be placed before shuttering is installed, with backfilling around the Beamform blocks to prevent movement during casting.