The second phase of constructing Vietnam's first underwater tunnel, Thu Thiem Tunnel in Ho Chi Minh City, will begin on March 8.
Sections of the tunnel will be dropped into the water to sink before being linked together in the Sai Gon River.
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| Thu Thiem underwater tunnel |
The Thu Thiem underwater tunnel is a part of the East-West Avenue project and will cover a total length of 1,490 metres, 370 of which are underwater, split into fours sections. Each section is 92.4 metres in length, 9.1 metres high, 33.3 metres in width and 25,000 tonnes in weight. They are made of concrete.
The sections were moulded at Phuoc Khanh Commune, Nhon Trach District, Dong Nai Province.
The first section will be transported to the site on March 7 and start sinking on March 8. It will take about 6 hours to transport the one section to the site and about 36 hours to sink down and install each tunnel section.
According to the execution team, the transportation date was determined after thoroughly considering weather observations; there are only a few days per month when the Sai Gon River's water flow is stable. This stability is necessary and means that only one section can be sunk in a month. The final section is expected to be dropped on June 5th, 2010.
In the case that sinking activities need to be delayed for safety reasons, tunnel sections can be anchored with two steel columns at the site.
After sinking is completed, the underwater tunnel will be connected with an entry section. It’s expected that the last connection with an entrysection at the bank of District 1 will be completed at the end of August, 2010.
The underwater tunnel will be put in trial operation in the first quarter of 2011.
