Tunnel Boring Machine Launched in Yangtze River Delta's First Tunnel Running Parallel to HSR

 Published:2021-12-28  【字体:

  At 10:18 on December 15, with the rotation of the blades, the "New Crossing" tunnel boring machine started to dig the large-diameter shield tunnel for Lot 2 of Shanghai Airport Connecting Line, which is the first tunnel in the Yangtze River Delta that runs parallel to the operational HSR with a small spacing and a long distance.

  Shanghai Airport Connecting Line is the first urban railway in Shanghai, starting from Shanghai Hongqiao Station and ending at Shanghai East Station. With a main line of 68.6km and a design speed of 160 km/h, it is the first demonstration urban railway interconnecting with the national railway network in China. Lot 1 and Lot 2 of the railway are constructed by Donghua Metro Co., Ltd. of China Railway Shanghai Group Co., Ltd. The shield tunnel of 4,939.8m-long Lot 2 runs parallel to Shanghai-Hangzhou HSR, with a minimum spacing of only 8.1m, making it the first large-diameter shield tunnel in the Yangtze River Delta that runs parallel to the HSR with a small spacing and a long distance.

  With a total length of 156m, a largest depth of 25.5m and a minimum spacing from the HSR subgrade of only 10.6m, the tunnel shield launching shaft is the largest and deepest foundation pit adjacent to the HSR subgrade in China at present. The construction participants have overcome the technical difficulties such as 1.5m ultra-deep and ultra-thick ground wall construction and limited-time hoisting of whole special-shaped steel cage for 56m ground wall. Through the development and application of railway/subgrade 3D "Smiley Face" Warning System with independent intellectual property rights, and the innovated confined water partition with N-jet deep ultra-high pressure rotary pile, they have achieved micro-disturbance excavation of deep foundation pits for HSR line, ensuring the operational safety of Shanghai-Hangzhou HSR.