Tseung Kwan O Extension
MTRC 611 Pak Shing Kok Tunnels
- Pak Shing Kok, New Territories, Hong Kong
- Mass Transit Railway Corporation (MTRC)
- Hyundai-Kier Joint Venture
- 2000 - 2003
HKJV Contract 611 comprising the Pak Shing Kok Tunnels, forms the final section of the southern branch, providing access to the depot at TKO. The alignment starts with 2 single-line running tunnels in the north and splits after the future planned Pak Shing Kok Station into 4 tunnels. The northern most section of the tunnels is below tide level and in close proximity to the Junk Bay landfill and was waterproofed. Total 5 tunnels have their portals in the south, where a reverse siding and a pair of tunnels feeding the depot are required in addition to the main tunnels. The 10m wide and 380m long main ventilation adit from Pak Shing Kok Ventilation Building branches to serve the running tunnels in 5.4m wide adits.
The geology of the area consists of volcanic rocks and consist mainly of welded fine- to coarse-grained ash tuff interlayered with distinctive pyro-clastic flow deposits.
Highly fractured and decomposed The Company provided the supervision and specialist support for the supply and application of the tunnel back grouting using micro fine cements and polyurethane grouts to seal the waterproof linings and associated works.