Stonecutters Bridge, Hong Kong: ground investigations and seismic criteria

A preliminary ground investigation was undertaken in 1999 as part of the site investigation for Hong Kong's Route 8. Additional information was also available from other ground investigations undertaken for recent reclamation works. While this information provided an overview of the ground conditions for initial scheming it was inadequate for detailed design of Stonecutters Bridge. A detailed ground investigation was therefore procured in 2001, which was undertaken in three separate phases over a period of two years and described in this paper. Structures with long periods require design response spectra. For long period structures design response spectra are required. For Stonecutters Bridge, these were developed for various return periods using a probabilistic seismic hazard assessment (PSHA). The effects of the local soil profile were also explicitly considered. This paper summarises the PSHA and how the effects of the local soil profile were taken into account. The methods used to determine the dynamic response of the bridge and the effects of non-synchronous motion of the foundations are also explained.