The Yuen Long Station topside development comprises six residential towers – four on top of the MTR station and two on the ground – providing about 2,000 residential units, retail podiums, landscape garden, clubhouse facilities and car parks. It also includes 50m long vehicular and pedestrian bridges over the existing tracks of the Light Rail.
Arup’s scope of services included structural, geotechnical and civil engineering as well as transport, risk and safety consulting. Our holistic planning of the design and construction sequence minimised the disruption to the rail operation and road traffic during construction.
126,400m² total GFA
50mspan vehicular and pedestrian bridges
1st‘rotary launching’ construction in Hong Kong
Safe construction atop busy operating railway lines
The development work is atop the open operating Tuen Ma Line and Light Rail. Our Rail (safety and risk) team utilised a risk assessment framework to devise a safe working sequence and risk mitigation measures to enable a smooth workflow while ensuring maximum protection was provided for the railway operation.
A unique foundation system was tailored to cope with the complex geological conditions at the project sites. By utilising a combination of foundation pile types, which includes driven steel tubular piles and shaft grouted pre-bored steel H piles, we achieved a robust design with lower foundation costs.
A top-down construction method was adopted for the basement at the southern podium to speed up the construction process and maintain project schedule.
Innovative ‘rotary launching’ method
The northern and southern sites of the development are connected by the vehicular and pedestrian bridges. As the bridges lie above the open tracks of the Light Rail and roadways, the main contractor (Sanfield) had engaged a heavy lifting specialist (Freyssinet) for an innovative ‘rotary launching’ installation method to minimise the disruption to the rail operations and the road traffic. Our works involve the design of the rotation platform and the associated structures. We have also arranged independent reviews from an international team to provide expert opinions to the entire rotation launching design.
This installation is the first-of-its-kind in Hong Kong. Instead of assembling the bridge above the at grade Light Rail tracks, we rotated the prefabricated structure from the southern site towards the northern site. Working with the lifting specialist, the team managed to launch and lower the two 50m span bridge structures within two single operations.
Setting a precedent
Originally, the bridge erection demanded over 100 nights of work during non-service hours. With this brand-new construction method, the team was able to shorten the construction time to less than 50 nights.
The steelwork fabricator (Goldwave) for the rotation assembly had conducted full-scale rehearsals of the rotation process in their fabrication yard. The giant circular truss platform was then mobilised and reassembled on the project site with minimal on-site welding. Contingency measures were proposed and prepared on site against foreseeable possibilities of equipment failure and/ or severe weather conditions.
The installation has successfully enhanced work efficiency and will be an exemplar of future rotary launching in Hong Kong.