New progress has been made in the west extension of Shanghai Railway Line 13. The construction of China's first embedded and inserted segment metro main line tunnel has begun

Shentong Metro Group introduced that on the morning of December 28, the shield tunneling machine, which is responsible for the first embedded and inserted tube tube tunnel boring in China, started smoothly at the site of the 101 mark of the west extension of Shanghai Metro Line 13. This time, the shield will be responsible for the tunneling task of the section of the west extension of Line 13 from Jizhi Road Station to the middle air shaft of Hongwei River. As the first metro tunnel constructed by the new type of embedded-socket joint technology in China, rapid joint connection will be adopted in this section instead of the traditional segment bolt connection, which will greatly improve the tunnel forming quality and the overall stiffness of the structure after completion.

In order to build a new type of rapid joint segment tunnel with high efficiency and quality, Shentong Metro has organized colleges and universities, construction participating units, experts and scholars to conduct several thematic studies and discussions on the structural stiffness of shield tunnel under geological conditions in Shanghai since 2017, and made innovations in the segment assembly method and joint form, and finally decided to adopt the new type of rapid joint segment.

Since entering the site, the construction unit has given full play to its resource integration ability and scientific and technological innovation ability. In view of the technical difficulties of segment assembly mode in the zone, it has actively joined hands with all parties to carry out adaptive transformation of the shield tunneling machine and study the new segment assembly process. By lengthening the shield tail and jack travel, the space for segment assembly and lap joint is guaranteed. Moreover, the erector was modified with the function of micro adjustment to ensure the assembly accuracy of 1.5 mm. The automatic gap measuring device and automatic segment selection system of shield tail segment were studied to ensure uniform shield tail clearance at each point of the segment. At the same time, through the combination of online and offline, the production and acceptance standards of the new segment were sorted out, the sequence of segment assembly and the key points of clamping were trained in practical operation, and the stroke positioning of segment assembly point was tested, which improved the success rate of segment assembly.

The smooth start of the shield machine not only opened the curtain of the shield construction of the west extension of Shanghai Metro Line 13, but also an important practice of the new rapid joint technology in domestic subway tunnel construction, which will play a positive role in promoting the continuous deepening of the integration technology of high-precision construction of subway tunnel.

As an integral part of the urban rail transit network, the west extension project of Shanghai Rail Transit Line 13 opens up a new fast route for connecting Hongqiao Business District with downtown and Pudong New Area through the connection with the previous project of Shanghai Rail Transit Line 13, which can reduce the passenger flow pressure of the National Convention and Exhibition Center and better improve the rail transit service level of Hongqiao Area.