Bangkok Blue Line Extension ©Sarvut Eksuwan ; Bangkok Blue Line Extension ©Sarvut Eksuwan ;

MRT Blue Line extension, Bangkok

Encircling Bangkok’s core business and cultural areas

The MRT Blue Line, or the Chaloem Ratchamongkhon Line, is Bangkok’s first MRT system line opened in 2004 and it is currently serving more than 360,000 passengers daily. Opening in September 2019, the Blue Line extension connects the existing line from Hua Lamphong station in the south and Bang Sue station in the north to complete Bangkok’s orbital rail network. As the lead consultant, Arup has been working with Italian Thai Development (ITD) on Contract 1 for two underground stations, Wat Mangkon and Sam Yot (locally known as Wang Burapha) and two intervention shaft structures in the centre of Chinatown, covering full multidisciplinary services including civil and structural, geotechnics, architecture, building services, alignment, fire engineering, tunnel ventilation and passenger movement analysis.

Project Summary

26m+ One of the deepest underground station in Bangkok

The Bangkok clay challenge

The geology at the stations which comprise a downward sequence of made ground, Bangkok clay, first (second/third etc.) stiff clay alternating with Bangkok aquifer sands and with a water table at about ground level. In general, the stations comprise a top-down cut-and-cover reinforced concrete box with perimeter diaphragm walls. The formation level of the base slabs is at approximately 26m to 30m below ground level and are ground bearing on the aquifer sand and clay. Therefore, the design of adequate toe levels of the diaphragm walls for groundwater cut-off and the basal stability at the formation of the base slab into the Bangkok aquifer and clay layer has been a major challenge.

Wang Burapha Station (Sam Yot Station) © Saravut Eksuwan Wang Burapha Station (Sam Yot Station) © Saravut Eksuwan
Wang Burapha Station (Sam Yot Station) © Saravut Eksuwan

Ornate stations to give new look

In contrast to the predominantly underground existing MRT stations with their generic grey granite and glass entrances, Arup has given a new look for the Wat Mangkon and Sam Yot (Wang Burapha) stations with multi-storey above ground buildings incorporating entrances, concourses and retail areas designed to reflect the architectural shop house style of the Rama V period.

The aesthetic design below ground for Wat Mangkon Station reflects the Wat Mangkon temple decoration in auspicious bright red colors, traditional Chinese fretwork and a coiled dragon ceiling elements. 


Reduce traffic congestion in China Town

The MRT Blue Line now running from Hua Lamphong to Tao Poon for a distance of 21km will increase ridership from 350,000 per day to 800, 000 a day when all extensions are complete and will help to reduce the very heavy traffic congestion on Yaowarat Road running through the centre of  the Samphantawong district (Bangkok China Town) and will significantly improve access to this district for locals and tourists alike.

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