In a tight spot

Soil nailing by May Gurney's Geotechnical team has helped maximise the tight spaces rig crews have to work in on the site of a new supermarket and car park in Rickmansworth, Hertfordshire.

The site is further complicated by a railway line to the south and a row of protected trees and pedestrian route on an embankment to the north.

Working as main contractor and subcontractor respectively, Kier and May Gurney needed to excavate the sloping ground to create a vertical bank that would allow them to build right to the perimeter of the 35m by 160m site - without disturbing the footpath and trees on top of the chalk embankment.

"The building's footprint will sit where the existing bank is," says Mike Cowan, May Gurney's Area Manager. "Without reinforcement, the excavation work needed to build there would dislodge the bank and the area above."

The project team originally looked at using sheet piles to reinforce the vertical bank following excavation. But the idea of using soil nails and shotcrete developed as it became clear how much easier the installation would be in such a tight area.

May Gurney's £100,000 share of the work was completed in mid February 2007, with the new supermarket scheduled to open in November 2007.

Click here to read the full story, courtesy of Ground Engineering.