Shenzhen Government Online
China’s largest tunnel machine to start boring
From: Shenzhen Daily
Updated: 2019-04-18

Work on Chunfeng Tunnel will start in mid-May with the arrival of the largest domestically made tunnel boring machine (TBM) in the city.

The 15.8-meter diameter of the mega TBM is equivalent to the height of a five-story building. It is said to be the largest TBM made in China. It will be assembled and used to bore the four-lane double-decked tunnel, set to relieve congestion on Binhe Road.

One of the major infrastructure projects in the city’s Go East strategy, Chunfeng Tunnel runs parallel to Chunfeng Flyover to the north. After the tunnel’s completion, a trip between Shangbu Overpass in Futian District and Xinxiu Overpass in Luohu District will take only six minutes.

The 5-km tunnel links Binhe Boulevard and the East Cross-border Expressway through the two overpasses.

It will be Shenzhen’s first single-bore tunnel with a double-decked interior, providing four lanes and two continuous emergency parking lanes. Traffic on the two decks of each tube will run in opposite directions.

To work with a TBM of this scale, there are a number of major technical risks that need to be managed effectively. The TBM will cross 11 fault zones of up to 431 meters wide and will negotiate a minimum curve radius of 750 meters.

Another point of concern for this project is settlement control as the tunnel goes underneath a residential area, the city’s Metro Line 9, and other urban buildings and public infrastructure.

To mitigate the risk, the contractor, China Railway Tunnel Group, came up with four circuit lines of air pressure control for the machine to minimize settlement during operation.

In another development, an underground project that links Nanping Expressway in the north and Guangzhou-Shenzhen Riverside Expressway in the Qianhai area in the south will be completed before the end of the year. The underground passage will enhance the road connectivity of Qianhai with the rest of the city. It will link Nanping Expressway, Binhai Boulevard and Guangzhou-Shenzhen Riverside Expressway, as well as several underground roads in the Guiwan, Qianwan and Mawan areas of Qianhai.