Recently, the Chongqing Guanjingkou Water Conservancy Project, which was built by the China Railway 18th Bureau Group, has successfully passed the completion acceptance, which marks the official start of the project.

Chongqing Guanjingkou Water Control Project

The Chongqing Guanjingkou Water Conservancy Project is one of the 172 major water conservancy projects for water conservation and water supply determined by the State Council. It is one of the first batch of PPP investment and financing reform pilot projects determined by the National Development and Reform Commission and the Ministry of Water Resources. . The pivot project is located in the main stream of Wubu River, a first-class tributary of the Yangtze River, and the reservoir dam site is located in Dongquan Town, Banan District, Chongqing City. 2) Type II water conservancy project.

The project started construction in March 2016. On August 8, 2020, the No. 6 pressure-free tunnel constructed by the China Railway 18th Bureau Group was completed, marking the completion of the 16.2-kilometer-long viewing port water conveyance tunnel.

Chongqing Guanjingkou Water Control Project No. 6 Pressure Free Tunnel

The construction of the project needs to overcome a series of difficulties and challenges such as underground water inflow, weak interlayers, broken faults, and karst caves. In order to ensure the smooth progress of the project, the project team of the China Railway 18th Bureau Group has adopted the new ultra-long-distance hard rock pipe jacking construction technology for the first time in China. This technology has the characteristics of high speed, safety, environmental protection and strong geological adaptability, which can effectively shorten the construction period. , to ensure construction safety and quality.

Hard Rock Pipe Jacking Machine

During the construction process, the project team optimized and transformed the pipe jacking machine and the relay room, and injected thixotropic mud synchronously, which greatly reduced the friction resistance and pipe stuck phenomenon during the jacking process, effectively promoted the construction progress, and created the highest The daily footage is 32 meters, and the highest monthly footage is 608 meters. The construction record of similar tunnels in China, the No. 3 pressure-free tunnel with a total length of 3,224 meters has created the world record for the longest single-hole pipe jacking construction, which is the largest diameter and ultra-long distance pipe jacking in the domestic water conservancy industry. The promotion and application of construction technology has accumulated rich experience.

Hard rock pipe jacking machine control room

Faced with the problems of pipe jacking power, thixotropic mud performance and stress monitoring, underground docking, stuck pipe, karst cave and pipe jacking machine retraction technology in the process of ultra-long-distance rock pipe jacking, the project team worked with construction, design and colleges and universities, etc. The scientific research departments have jointly launched research and developed new technologies and processes such as "thixotropic mud to reduce resistance" and "pipeline stress monitoring" in long-distance pipe jacking construction, to overcome construction problems one by one. It has successively obtained more than 20 patents, construction methods and thesis results, and has been listed as "Demonstration and Promotion Project" and "Innovative Construction Research and Implementation Project" by the Ministry of Water Resources.

Has obtained more than 20 patents, construction methods and thesis results

It is reported that after the project is completed and put into operation, it can effectively solve the water supply problem for nearly one million people in the urban development area of eastern Chongqing, meet the water diversion and farmland irrigation needs of residents along the line, and promote the high-quality economic and social development of Chongqing. Editor/He Yuting