In support of the Hong Kong-Zhuhai-Macau Bridge, the Tuen Mun-Chek Lap Kok Link (TMCLKL) provides a strategic linkage between the Northwest New Territories and the Hong Kong Boundary Crossing Facilities (HKBCF), the North Lantau and the Hong Kong International Airport (HKIA).
The 9km long dual 2-lane carriageway consists two major sections: the Southern Section which connects the HKBCF and North Lantau on viaducts and the Northern Section which connects Tuen Mun Area 40 with the HKBCF via a sub-sea tunnel.
The strategic link reduces the travelling time between Tuen Mun South and HKIA from 30 minutes to 10 minutes. It not only helps divert traffic flows to relieve the existing traffic conditions of North Lantau, the Lantau Link and Tuen Mun Road, but also provides as an alternative route to the HKIA, thus reinforcing the HKIA as a regional aviation hub.
Southern Section Viaducts
Arup supported Gammon during tender of the D&B Contract and the majority of the design for the Southern Section Viaducts. The marine section crosses about 2km of water including the Tung Chung Navigation Channel requiring a span of 200m; whilst the land section at North Lantau overpasses existing railway lines with skew angles requiring spans of up to 100m.
In total there are about 9km of viaduct structures, which were designed as prestressed concrete girders constructed by precast segmental method.
Northern Section Tunnel
We also provided multidisciplinary engineering design for the Northern Section Tunnel as the Contractor’s Designer. Our close collaboration with Dragages-Bouygues Joint Venture has contributed to the creation of an economic, safe and sustainable design with an overall aim of mitigating risk at every step.
Over 4.2km in length and running to a depth of 60m beneath the sea, the tunnel accommodates three lanes of traffic at the northern entrance, requiring a world-record external diameter of 17.6m for a Tunnel Boring Machine (TBM) ever used for construction.
These extraordinary requirements stemmed from an innovative change in design for the proposed three lane northern approach ramp structure, from a conventional deep cut and cover tunnel to a large diameter bored tunnel, thereby reducing risk and significantly expediting construction. In order to launch and provide sufficient working space around such a large machine and another situated by its side for each of the twin tunnel bores, Arup designed the first cellular diaphragm wall cofferdam ever constructed in Hong Kong to provide an open strut free environment which has since been adopted by others following its great success.