UNDERLENGTH PILES on a prestige Hong Kong Central development have prompted a major investigation and extensive remedial works, it emerged last month.
Hong Kong's Building Department is now considering whether to take action to against the firms involved. The investigation was launched into the £55M ($90M) foundation contract after more than 80 of the concrete piles were found to be defective.
Main contractor Aoki only discovered the problem after an anonymous tip-off last October. It appears that piling records may have been deliberately falsified by a local piling subcontractor - since understood to have ceased trading.
Under a complex contractual arrangement, the work had been sub-let first to Bachy Soletanche which had in turn then let the piling to German contractor Bilfinger & Berger. The package was then finally subcontracted to the local firm now under suspicion.
Ove Arup & Partners (Hong Kong) is the registered structural engineer.
Building Department chief structural engineer PL Ip said: 'Under the Hong Kong Buildings Ordinance and Regulations, it is the statutory duty of the registered contractor to provide continuous supervision and the registered structural engineer to provide periodic supervision on building works for which they are responsible.'
The piles are designed to support a shopping centre forming part of the Phase 2 development of the new Hong Kong Mass Transit Railway station. Defective piling is believed to be valued at £9M. Diameters range from 1.5m to 2.5m, and each should have been keyed into the granite bedrock at depths of 30m -70m to resist uplift forces.
Sources close to the project confirmed that the defective piles had been installed without the specified 5m key into the rock.