Project name: Yangzhou Slender West Lake Tunnel
Constructor: China Railway 14th Bureau Group
Shield model and diameter: Herrenknecht 14.93m slurry shield
Product used: CONDAT WR89NG; CONDAT HBW； CONDAT GR130EP2

Project overview:

The starting point of the project is located at the intersection of Weiyang Road and Yangliuqing Road. After passing Yangtze River North Road eastward along the center line of Yangliuqing Road, it turns right at an angle of 37 ° to Slender West Lake. After passing Songjiacheng River, the upper layer intersects Youyi Road at grade, the lower layer crosses Youyi Road, crosses Yudai River, and connects with Caohe West Road.

Outer diameter of tunnel Φ 14.5m tunnel section. To make full use of tunnel space, the tunnel is arranged as a two-layer section with two lanes on each floor. The width of a single lane is 3.5m and the clear height is 4.5m. The traffic flow direction of the lower lane is from west to east, and the traffic flow direction of the upper lane is from east to west.

The total length of the shield tunnel involved in this project is 1275 meters. It starts from the shield working shaft in the east of the lake, and then goes west through the Slender West Lake Scenic Area, and then arrives at the shield working shaft in the west of the lake for removal and hoisting.

Construction environment:

There are various buildings, roads and famous scenic spots along the designed tunnel. The shield will pass through the section of Yangliuqing Road between Weiyang Road and North Yangzijiang Road, Yangzhou University of Education, the Party School of the State Administration of Taxation, Shugang Slender West Lake Scenic Area, the North Gate Site and other immovable cultural relics, as well as various rainwater pipes, power pipes, communication pipelines and other risk facilities in Caohe Road.

Overview of project difficulties:

The construction of undercrossing thin West Lake and Songhe River is the difficult point of this project. The lakes that the shield machine passed successively are: Songjiacheng River and Slender West Lake. The maximum gradient of the shield section is 5.0%. The minimum horizontal turning radius is 1500m, the minimum vertical turning radius is 4000m, and the maximum water pressure at the bottom of the shield machine is 3.92bar
The main shield section of Yangzhou Slender West Lake Tunnel is full section hard plastic clay stratum. This geological structure is also a world-class problem in shield construction.