Connecting cities with a bridge
The 55km-long Hong Kong-Zhuhai-Macao Bridge (HZMB) is the first cross-boundary land link connecting Hong Kong, Zhuhai and Macao. The bridge is the longest bridge-cum-tunnel sea crossing in the world.
The HZMB Hong Kong Section comprises the construction of the Hong Kong Link Road (HKLR) and the Hong Kong Port (HKP). The HKLR is a 12km dual three-lane carriageway connecting the main bridge and the port. It comprises land and marine viaducts about 9.4km in length, a 1km tunnel and a 1.6km road section.
Hong Kong Port is located on a piece of reclaimed land of 150 hectares at the waters off the north-east of the Hong Kong International Airport (HKIA).
There’s a passenger clearance building (PCB) which provides passenger clearance services, vehicle clearance plazas (VCPs) and public transport interchanges (PTI) at the HKP.
The HZMB connects three places, reducing the distance and travel time between them. This has created a one-hour living circle in the Pearl River Delta region, which has boosted the Greater Bay Area’s economic development and enhanced Hong Kong’s position as a hub.
Did you know …
The HZMB is the longest bridge-come-tunnel sea crossing in the world.
The PCB roof is formed by 45 large-scale prefabricated modules. The area of the largest roof module is approximately 60m x 25m with a weight of approximately 670 tonnes, which is larger than a standard Olympic-size swimming pool.
Project achievements and benefits
The HZMB will be of strategic importance to the further economic development of Hong Kong, Macao and the Western Pearl River Delta (PRD) region, by significantly reducing transportation costs and time.
Travelling time between Zhuhai on the western bank of PRD, and Kwai Chung Container Port and the airport on the other side will be reduced by more than 60% and 80%, respectively, thanks to the bridge. It also means that the Western PRD will fall within a reachable three-hour commuting radius of Hong Kong.
The bridge also boosts Hong Kong’s tourism, finance and commerce industries. In particular, it enhances the region’s position as a trade and logistics hub, as it makes better use of the airport and container port in Hong Kong.
Different types of plants were used to provide greenery and colour in different patterns covering over 30% of the Hong Kong Port. As well as emphasising the green landscape, the project contributed to sustainable development via creative engineering design, including independent sewage treatment system, district cooling system, eco-friendly building design, non-dredge reclamation method, and more.
How the work was done
Challenging iconic design with an innovative construction method
With a wavy roof designed to simulate undulating waves, the passenger clearance building (PCB) is an iconic building standing at the HKP next to the airport.
To tackle the challenge of airport height restrictions, an innovative construction method was adopted to construct the PCB's roof by using the prefabricated modules assembly method.
The large-scale prefabricated modules were lifted up one by one, pushed into position horizontally and connected together. Problems posed by the huge size, as well as the airport height restrictions, were overcome.
The method advanced the construction progress, enhanced the quality of works and reduced the risk of working at height. Different from the ordinary prefabricated modules, the roof modules were composed not only of structural steel frame but also the pre-installed building services, as well as architectural builder works and finishes, thus also saved on-site construction time.
Environmental innovative reclamation technology
Non-dredge reclamation was the first-ever reclamation method adopted in Hong Kong. It greatly cut the amount of dredging and dumping of marine mud by about 22 million m3 and reduced the use of approximately half of the backfilling material.
This led to a lower impact on water quality and less marine construction traffic during the building stage. This helped to preserve marine ecology, especially the habitat of the Chinese white dolphins.
The HKLR viaduct section features long spans as the carriageway crosses two navigation channels and Sha Lo Wan Headland, a designated Site of Archaeological Interest, where no construction works were allowed.
A massive, bespoke straddle carrier was used to construct the long-span viaduct of 180m in length. At the time it was erected, it was the longest, dual three-lane prestressed precast concrete bridge span in Hong Kong.
The design minimised the visual and environmental impact and has also become a feature of the area, complementing the natural scenery of North Lantau.
Innovative methods adopted
The HKLR viaduct, mainly situated at open waters, is the first bridge in Hong Kong to adopt prestressed precast pier construction method and precast concrete pile cap shells to minimise underwater works. This ensured a safer working environment and eliminated tidal constraints.
Floating concrete batching plant was introduced, which was the first of such facilities in Hong Kong and significantly reduced the logistics and ensured the best quality of concrete produced.
The construction of two separate tunnel tubes of the HKLR to cross under the existing Airport Express Line (AEL) is one of the most challenging works for the HZMB project in Hong Kong.
As the AEL is an important railway link between Hong Kong International Airport and the central business district, the normal and safe operation of the AEL must be maintained at all times.
To ensure undisrupted operation of AEL during the tunnelling works, box jacking was adopted – the first time it was used at such scale in Hong Kong. It involved pushing the constructed tunnel box segments forward by hydraulic jacks sequentially in a “caterpillar” motion, with a design jacking force of 19,400 tonnes – enough to lift 70 empty Airbus A380s in one go.