The Cross-river Tunnel with the Largest Diameter in China Contracted by STEC—Wuhan Sanyang Road Tunnel Starts

2016-04-27

On April 27, the cross-river with the largest diameter in China Constructed by STEC — Wuhan rail transit line 7 Yangtze River tunnel shield in Sanyang Road starts formally.

The rail transit line 7 Yangtze River tunnel in Sanyang Road is the first “2 in 1” highway and railway tunnel in China and is also the cross-river shield tunnel with the largest diameter in China so far. Whether in terms of internal structure of tunnel or in terms of construction difficulties, it creates a lot of the most excellent achievements in the national rail transit projects. The tunnel adopts 2 SPB shield tunneling machines manufactured by Herrenknecht AG with the super large diameter of 15.76 meters, which is “the first largest in China and the third largest in the world” in terms of diameter and is equivalent to height of 5 floors of building. The SPB shield tunneling machine is the largest in China at present and is nearly 4000 tons in total weight equivalent to weight of about 4000 cars, 167 meters in length and 20 thousand tons in total thrust.

Cross-river tunnel in Wuhan Sanyang Road, connecting Wuchang and Hankou, is the cross-river section of Wuhan rail transit line 7 and the control engineering of the whole tunnel and the important engineering for rejuvenating Wuhan. This tunnel includes two lines including left line and right line, in which each line is 2590 meters in length. After completion of this tunnel, the upper layer will be the discharge flue of the highway tunnel; the middle will be the running lane of the highway tunnel and will be provided with unidirectional three lanes with the width of 3.5meters; the lower layer will be the running lane of the subway line 7 and its escape way, cable tunnel and discharge flue. The internal structure of the cross-river tunnel adopts the synchronous construction of full cast-in-place structure, thus becoming the first super large shield tunnel adopting the construction scheme of full cast-in-place structure. In the tunneling process of the shield tunneling machine, its rear part with a distance of about 500 meters from the shield tunneling machine will pour three floors of building compartments within the tunnel at the same time, which is equivalent to build a viaduct for urban expressway within the tunnel.

Completion of Wuhan rail transit line 7 Yangtze River tunnel in Sanyang Road has an important and profound significance to build the stereoscopic cross-river traffic corridor, improve the residents’ travel environment in Wuhan. It will become another landmark traffic facility of Wuhan city together with “the First Bridge of Yangtze River” (Wuhan Yangtze River Bridge) open to traffic in 1956, “the First Tunnel of Yangtze River” (Wuhan Yangtze River Tunnel) open to traffic in 2008 and the first cross-river subway (the first-phase engineering of rail transit line 2) open to traffic in 2012.