Design project of world's largest urban under-lake tunnel is won by Second Highway Consultants

Source:Second Highway ConsultantsTime:2018-11-01

Recently Second Highway Consultants has won the bid for Lot 2 (Nanhu section) of the design project of the double-lake tunnel, with a contract amount of RMB 213 million.

With a full length of 8 kilometers, a designed speed of 50km/h, a total investment of RMB 13,800 million and a construction & installation cost of RMB 8,600 million, Section 2 (Nanhu section) will be constructed in accordance with the standards of two-way six-lane urban trunk roads. With two underground interchanges and two entries & exits, the Nanhu section is China's longest and the world's largest urban under-lake tunnel. The tunnel has a shield diameter (segment outer diameter) of 15.5 meters, ranking first in the Chinese mainland and third in the world.

The overall construction conditions of the project was complex, with lakes, mountains, karst development areas, compound strata and full face hard rock areas along the line, posing a higher challenge to large-size shield design. The surroundings of the tunnel are sensitive. The tunnel will start from the East Lake (a national 5A scenic area), cross three subway lines, two urban viaducts, the intercity railway corridor, one cultural relic preservation area and several positions close to high-rise buildings. In terms of comprehensive shield technology difficulty, the project ranks first in the world.