Restricted site access, steep gradients, lack of working space and an underground tunnel network have made Hong Kong piling contractor B&G Engineering's Belcher Gardens contract one of its most difficult to date. Working under a foundation subcontract with Sunley Construction, B&G Engineering is installing 139 H-beam piles using Sandvik's Centrex System, which allows piles to be drilled through overburden and into rock in a single pass. Work is being carried out for Ronex Development, whose Belcher Gardens is a new residential development on Hong Kong Island, with nine 50 storey towers to be built over three phases. Other phase one foundation work includes 84 , 2.8m diameter and 51, 1.5m diameter bored piles installed by Sunley. Underground
ex-military tunnels and shelters have presented an unusual problem. Where tunnels lie close to the surface, they are filled with concrete, and where piles intercept deeper tunnels the pile will be permanently cased.