Hong Kong-Zhuhai-Macao Bridge Hong Kong Link Road to be completely connected in April (with photo)
The Highways Department (HyD) today (April 13) said that the casting of all tunnel box segments in the Scenic Hill Tunnel section of the Hong Kong Zhuhai-Macao-Bridge (HZMB) Hong Kong Link Road (HKLR) has been completed and the last part of the tunnel box segment is being jacked to its final position underneath the Airport Express Line (AEL). Together with the connection of the mainline bridge decks of the HKLR viaduct section in late March this year, the 12-kilometre long HKLR will be completely connected in April, signifying the achievement of a key milestone of the HZMB Hong Kong project.
The HKLR is a dual three-lane highway about 12km in length connecting the HZMB Main Bridge in the Mainland and the Hong Kong Boundary Crossing Facilities (HKBCF). It comprises (i) 9.4km of land and marine viaduct; (ii) a 1km-long tunnel through the Scenic Hill; and (iii) 1.6km of at-grade roads in the reclamation area along the east coast of the airport. Since the commencement of the HKLR construction in mid-2012, the project team and frontline workers have overcome many challenges.
To build the HKLR in close proximity to one of the busiest airports in the world - Hong Kong International Airport - the HyD has faced various difficulties and challenges during both the design and construction stages. The airport height restrictions (AHR) have imposed severe constraints to the design of the HKLR affecting the vertical and horizontal alignments of the viaduct, thus limiting the choices of construction method and plants to carry out the works. In those areas with very low AHR adjacent to the South Runway, some works of the viaduct construction must be carried out at nighttime when the runway is closed. Sophisticated height detection equipment was installed to ensure that constructional plants were all working within the AHR.
As regards the construction of Scenic Hill Tunnel, four different construction methods were adopted to cater for the different and complex ground conditions and topographical constraints. They comprise the drill and blast method through Scenic Hill, the mined tunnel method underneath the Airport Road section, the cut and cover method at the reclamation area and the box jacking method of the tunnel box segment underneath the AEL. The most arduous works were those carried out underneath the AEL. The HyD adopted an advanced approach using the box jacking method to form this section of tunnel to avoid affecting the normal operation of the AEL. The tunnel box segments were cast first, then excavation was carried out at the leading face of the box segments, which were then pushed forward one by one using hydraulic jacks underneath the AEL. At present, the last bit of the tunnel box segment is being jacked into place. The size of the box segment is approximately 14.5 metres in length, 23.5m in width and 14m in height. Its weight is about 5 000 tonnes, which is equivalent to the total weight of 27 Boeing 747 jumbo jets. This last bit of the operation is targeted to be completed by next week at the earliest, thus signifying the complete connection of the whole HKLR.
In the meantime, the road surfacing works and installation of associated road facilities for the HKLR are being completed successively as planned. Concurrently, the HKBCF works including the passenger clearance building, ancillary buildings, bridges, the vehicle clearance plaza and associated facilities are also being carried out at full swing. In accordance with the current works progress, the HyD is confident that the HZMB Hong Kong projects can be completed by the end of 2017 and achieve readiness for commissioning.
Ends/Thursday, April 13, 2017
