Ningbo Yongjiang Tunnel is built on Yongjiang River. How was it built at that time?

Yongjiang underwater tunnel is the first large-scale underwater traffic tunnel built on soft soil foundation by immersed tube method in China. 1995165438+/kloc-0 was completed and opened to traffic on October 8. Its completion fills the gap in the application of the new technology of "immersed tube method" in the construction of underwater tunnels on soft soil foundation in China, and creates a new era of empty immersed tube tunnels in China. Cai Xiuke, assistant director of Guangzhou Maritime Rescue and Tiger Fighting Bureau of Ministry of Communications and director of the First Engineering Office, presided over the construction of Fujiang Tunnel.

Yongjiang Underwater Tunnel is located at the mouth of Yongjiang River in zhenhai district, Ningbo City, Zhejiang Province. It is a single-hole two-lane automobile tunnel with a total length of 1, 0 1.9 meters and an underwater section of 420 meters. It consists of five sections of 85× 65,438+0,654 38+0.9 m reinforced concrete large immersed tubes. It is built on the soft foundation of yellow muddy clay with marine deposition and saturated flow molding. River siltation is serious, and the measured siltation intensity is 16cm/ day. Using riprap to backfill the foundation and special dredging equipment, the project was successfully completed, which accumulated experience for building immersed tunnel on soft soil foundation in China. The completion of Yongjiang Tunnel broke the integration of river and bridge, and was praised by experts as a milestone in the development of China's transportation industry. It represents the latest level of immersed tube underwater tunnel construction technology in China today, and creates a successful road for China to build underwater tunnels in the vast soft soil areas along the Yangtze River, Pearl River and Yellow River in the future. "Ningbo Yongjiang immersed tube tunnel construction technology" won the second prize of 1997 for scientific and technological progress of the Ministry of Communications.