On January 16, it was learned from Nanchang that the construction of the Honggu Tunnel, which has attracted much public attention, will be fully launched.

It is understood that the Honggu Tunnel is financed and constructed by Nanchang Municipal Public Investment Holding Co., Ltd. According to the plan, the tunnel is located between the Nanchang Bridge and the Bayi Bridge (about 1.3 km from the Nanchang Bridge and about 2.3 km from the Bayi Bridge), connecting the Honggutan New Area with the old urban area. The main line is about 2,650 meters long. The project is designed to the standard of an urban arterial road with two-way six lanes, and the design driving speed is 50 km/h.

To effectively ease traffic pressure, the Honggu Tunnel will adopt the design concept of "rapid river crossing, three-dimensional traffic, multi-point evacuation, and east-west connectivity," with multiple entrances and exits on both banks connecting to the regional road network. Among them, on the west bank, a main line entrance and exit will be set on the east side of Fenghe Middle Avenue, and a pair of entrances and exits will be set on the east side of Honggu Middle Avenue; on the east bank, an underground "double-Y" interchange will connect to Yanjiang Middle Avenue, ensuring that cross-river traffic can be quickly distributed through Yanjiang Middle Avenue and the east-west roads connected to it (Minde Road, Zhongshan West Road, Chaoyangzhou Middle Road, and Chaoyang South Road).

The Honggu Tunnel project is the largest immersed tube tunnel on an inland river in China, with many difficulties and highlights, including high flood control requirements for the Gan River, a large-scale project cofferdam, deep filling height, high risk of a deep foundation pit adjacent to water within the cofferdam, and the fact that it is an underwater full interchange; floating transport under high water level differences, treatment of the waterstop at pipe section joints and design treatment of joint watertightness; and underwater trench rock blasting and excavation are all technically complex and difficult to construct.

It is reported that the construction period of the Honggu Tunnel is 42 months. After the tunnel is completed, it will greatly ease the cross-river traffic pressure on the Nanchang Bridge and the Bayi Bridge and quickly connect the economic circles on both banks. The construction of the tunnel will further improve Nanchang's "ten horizontal and ten vertical" road network structure and, through the construction of a rapid arterial road network, strengthen internal and external traffic connections.