It is the second longest tunnel on the Yangtze River, with a total length of 6445 meters. It is the largest diameter shield tunnel under construction in China, with an excavation diameter of 16.09 meters; it is the highway shield tunnel under construction with the highest water pressure in China. The maximum water pressure is 82 meters.

The Jiangyin Jingjiang Yangtze River Tunnel Project is one of the 44 river-crossing passages in Jiangsu Province approved in the "Layout Plan for Crossing Channels of the Yangtze River Trunk Line (2020-2035)". It is located between Jiangyin Bridge and Taizhou Bridge and is about 5 kilometers away from the downstream Jiangyin Bridge. It is about 27 kilometers away from the upstream Changtai Yangtze River Bridge under construction. The project will start temporary construction in November 2020, starting from Jingjiang Gongxin Highway in the north to Furong Avenue in Jiangyin in the south, and crossing the Yangtze River in the form of a shield tunnel. The length of the line is about 11.825 kilometers, of which the tunnel section is 6,445 meters long. The entire line is constructed in accordance with the standard of a two-way six-lane expressway, with a design speed of 80 km/h and a roadbed width of 33 meters. The total investment in the preliminary design estimate of the project is approximately 14.36 billion, and the construction period is 60 months.

Pioneered a new design for waterproofing of coupled dual-channel gaskets concentrated on the outer side of the tube segment: for the first time, two waterproof gaskets were centrally arranged on the outer side of the tube segment. Through waterproof theory and experimental research, a scientific waterproof structure layout was obtained, forming both internal and external repairs. A new comprehensive waterproof system for ultra-high water pressure shield tunnels.

The first new concept of fast and direct evacuation and rescue channel design: for the first time, the new evacuation and rescue concept of the coordination of shield section evacuation channels and cut-and-cut section roadways is considered. The rescue vehicle goes directly to the evacuation channel at the bottom of the shield tunnel through the evacuation channel from the cut-and-cover section. People quickly reached the rescue vehicle via the evacuation stairs, realizing rapid evacuation and rescue in long-distance tunnels.

The first non-embedded structural health monitoring technology to build and maintain integrated information management new technology: based on precise measurement of shield tunnel structure internal force inversion analysis software and full coverage of measuring points, pertinence to structures with diseases or large dislocations Monitoring, inversion analysis, and structural health monitoring.

The first new demonstration of a green tunnel in a mobile environment-friendly space: The project focuses on the five aspects of structural safety and durability, safe and comfortable driving, convenient evacuation, resource conservation and environmental protection, and the first establishment of a green tunnel management system, evaluation system, technical system, and standard system .

On September 2, the Jiangyin Jingjiang Yangtze River Tunnel successfully completed the first section of the roof pouring, and the prototype of the rectangular main structure of the tunnel cut-out section began to appear.

The Jiangyin Jingjiang Yangtze River Tunnel Project starts from Jingjiang Gongxin Highway in the north and ends at Furong Avenue in Jiangyin in the south. It uses a shield tunnel to cross the Yangtze River. The roof poured this time is located in the seventh stream of the project, which is the transitional roof of the subsequent section of the working well and the open-cut and buried section. The roof concrete of the main structure of the tunnel has higher requirements for crack resistance. The headquarters organized a construction team to carry out research on the crack resistance performance of mass concrete, optimized the concrete mix ratio, adopted advanced ice making equipment, and added crushed ice to the concrete to reduce mold entry. Temperature improves the crack resistance of concrete.

During the pouring construction, management personnel at all levels stood by to supervise the whole process of concrete mixing, transportation, pouring, and vibrating. The on-site construction work team closely cooperated, and the project carried out various operation procedures in an orderly manner. The smooth pouring of the roof of the first section of the Jingjiang Yangtze River Tunnel in Jiangyin marks a new stage in the construction of the main structure of the tunnel, laying a solid foundation for the subsequent section capping and shield machine launch.

At present, the project is carrying out the construction of the shield machine's initial working well and subsequent sections, open cut and buried section, and open cut section. The shield machine is expected to be assembled and commissioned at the end of September. The preparatory work is advancing at full speed. Editor/Sang Xiaomei