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MTR Extension of Island Line: A feat of engineering
  • “Engineering is a practical field, which is all about improving the livelihood”
  • “Engineering is a practical field, which is all about improving the livelihood”

“Engineering is a practical field, which is all about improving the livelihood”

Jun 2015

Long regarded as the epitome of convenience, MTR railway is a life-changer to any neighbourhood in Hong Kong. Residents of the Western district waited for years for the extension of the railway service into the district, which finally began service last December. The three new stations, Sai Ying Pun, HKU and Kennedy Town, were built with the adoption of advanced and proven technologies with many newly designed and user-friendly facilities, showing the effort of MTR to provide top-notch transportation for the Hong Kong public. 

The Western district is one of the oldest residential areas in Hong Kong, and many old buildings were densely built decades ago. It is not difficult to understand the construction of this railway extension had faced a myriad of technical difficulties. “The ground condition from Sheung Wan station westward is extremely complex, and the railway tunnels are built in soft ground but between many building piles.” said Francis Li Shing-kee, MTR’s Head of Operating. Hence, a new ground stability technology, called ground freezing, was used. The soil along the tunnel rout was first frozen for a few months in order to make way for the tunnel excavation.

It was also the first time for MTR to use “Rigid Conductor for Overhead Line” to generate power for the operation of trains. Solid copper conductor rails, instead of power supply cable lines commonly used in Hong Kong, are installed at the tunnel soffit. This new system not only enhances its reliability and maintainability, but also helps to minimise power loss in transmission. If there is any physical damage to the system, the damage should be lessened as repairing work can be done much quickly.

The extension has breathed new life into the Western district. The hilly topography of the Western district is a hindrance for most elderly residents, making them very difficult to travel within the district. It is straining to walk up from Des Voeux Road West to Bonham Road, especially during summer. Weather-proof and fully-ventilated long adits and lift-only entrances are provisioned in Sai Yin Pun station and HKU station. “Some elderly residents told me they could now easily go to some other places for grocery shopping.” Mr. Li said.

The new stations use only high-capacity lifts, which are also used in other countries. However, the number and capacity is much lower than those used in the West Island Line. For deep stations, lifts are the only sensible choice as it would take as many as 16 escalator flights to carry passengers from station entrance to concourse. These new lifts can be used in case of fire too, and the MTR engineering team and operation team have worked with the government departments to ensure its safety. There are separated fire compartmentations between lift shafts and fire curtain provided at each lift door could prevent entry of smoke into the lift shaft.

Many residents in the Western district have lived in this area for many years. While many of them welcome the railway, they are adamant to preserve the district’s unique characteristics. For example, Kennedy Town boasts a “Tree Wall”, which has been standing there for more than a century. Twenty-six banyan trees grow on top of the 200-metre wall, and the combination of penetrating roots and age-old stone creates a serene and magnificent sight. Mr. Li said that the Kennedy Town station was originally planned at a location where we needed to demolish the “Tree Wall”. After consulting with the residents and the District Council, the MTR redesigned the station layout, making the preservation of the “Tree Wall” possible.

“As a railway operator, I feel proud to see that most of the Western district residents enjoy our railway service and also offered very positive feedback on our station design,” Mr. Li said. Engineering is a practical field, which is all about improving the livelihood. Nothing can bring more joy to an engineer other than knowing one’s hard work has led to positive changes in the community. It is not difficult to see why Mr. Li derived so much satisfaction from his work surrounding the development and operation of the West Island Line.

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