Progress of rail (metro) tunnel construction in Singapore - past, present & future

The Land Transport Authority (LTA) of Singapore is responsible for the implementation of the Mass Rapid Transit (MRT) System on the island. Underground construction for the rail network commenced in the early 1980s and the whole project was divided into two phases, comprising 67 km of line and 42 stations. The construction was carried out between 1983 and 1990 and this undertaking, at its peak, was one of the most extensive tunnelling projects in the world at that time. Following the completion of the main MRT network in 1990, another major milestone was achieved in Singapore's public transportation history with the commencement of the construction for NorthEast Line (NEL). The NEL Project was authorised in January 1996 and opened on 20th June 2003 at a cost of $4.6 billion. With the completion of NEL and the extension of the main line to the Changi Airport, a total route length of 138 km of rail has now been laid. LTA continues its expansion of the rail network into the millennium with the implementation of the Circle Line (CCL). By 2010, a further 34 km route length of rails will be laid fully underground. The CCL has been designed in order to link the radial rapid transit lines running into the city. This system, like NEL, will be a fully automated and wholly underground rapid transit system. It will serve the developed areas around Marina Bay and Suntec City with a capacity of up to 20,000 passengers per hour per direction and extend from Paya Lebar, Serangoon, Bishan, Buona Vista to Harbourfront. CCL will interchange with the existing North-South, East-West and North-East lines, offering commuters the option of bypassing the city and providing a shorter train journey to the outer urban areas. Other transit lines to meet the future transportation needs of Singapore are on the drawing board and are either in the evaluation or the feasibility study stages. From the onset, the LTA has endeavoured to strike a balance between satisfying the social needs of the population in terms of ridership and on deciding the location of the stations in terms of constructability. In evaluating the aspect of constructability, some of the criteria considered are alignment, geological conditions, environment, topography and, most importantly, the available tunnelling methods. Tunnelling during phase one of the MRT construction was mainly carried out using Greathead open-face shields with backhoe or roadheader. By the time the NorthEast Line project started in the mid 1990s, tunnelling technology had advanced significantly with Earth Pressure Machines (EPBMs) becoming common. Of the 16 TBMs deployed on the North East Line, 14 were EPBMs, and 2 were open-face Greathead type machines. Singapore is in a constant state of change and this fact is clearly evident by the continued addition of buildings on the scarce land bank. As the underground network of tunnels also extends to meet future demands, it will require that thought be given to different rail tunnel requirements. This may come in the form of stacked tunnels, smaller twin bore tunnels or even very large single bore tunnels. This paper discusses the TBMs used from phase one to the present day and also highlights the requirements that may affect the choice of tunnelling machines in the future. (A). "Reprinted with permission from Elsevier". For the covering abstract see ITRD E124500.

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  • Authors:
    • OW, C N
    • SEAH, T P
  • Publication Date: 2004-7


  • English

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  • Accession Number: 01011547
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Dec 19 2005 3:16PM