By rosebell
Being constructed using the largest diameter shield machine in Hunan Province, China, the Changsha Xiangya Road river-crossing tunnel was opened to traffic on July 5th.
The advantages of inaugurating this tunnel will be decreasing traffic pressure on the nearby Yinpenling Bridge and Yingpan Road Tunnel, as well as achieving the objective of interconnecting networks and smoother traffic flows.
In order to building this tunnel TBM Xingsheng, which is a CRCHI (China Railway Construction Heavy Industry Corporation Limited) large-diameter slurry TBM was used, whereas it commenced construction of the left line tunnel on March 30th 2021 and the date of starting the right line tunnel was June 20th 2022. The twin-tunnels final breakthrough was on March 12th 2023.
Stretching from Yuehua Road in the Yuelu District in the west to Furong Road in the Kaifu District in the east, the Xiangya Road river-crossing tunnel project’s total investment is 5.33 billion yuan.
While the whole length of project is 4,180 meters, almost 1.4 kilometers of it belongs to the river-crossing section that was constructed by shield machine tunneling methods. As the first two-way six-lane river-crossing tunnel in Changsha, the left line TBM tunnel is 1429 meters long, and the right line TBM tunnel is 1425 meters long.
Passing beneath the Xiangjiang River dike four times, the shield machine tunnel crossed two riverbed fracture zones with more than 450 meters in length twice.
With maximum excavation diameter of 15.01 meters, the Xingsheng slurry TBM had an overall length of approximately 129 meters and in order to effectively resolving the impact issues on the cutterhead during the excavation of riverbed rock layers and composite strata, this machine adopted a heavy-duty composite cutterhead, high-wear and long-life cutting tools and a 7.6-meter heavy-duty main bearing design.
The frequency of cutter replacement was reduced, the excavation efficiency is increased, and the smooth construction of the tunnel was ensured.
