The excavation of the world's largest underground pump room has been completed
On March 30, 2023, the excavation of the main pump room of the Shigu Water Source Project in central Yunnan, which was surveyed and designed by Yangtze River Design Group, was completed. Significant progress was made in the construction of the project, laying a solid foundation for the concrete construction of the main pump room and creating favorable conditions for the comprehensive transition of underground pump station system excavation to concrete construction in 2023.
The Shigu Water Source Project is arranged as a first level pumping station, which draws water from the right bank of the Jinsha River located about 1.5km upstream of the mouth of the Chongjiang River. After sedimentation through a 1.27km long diversion canal, 135m3/s of Jinsha River water is transported to the underground pumping station located upstream of Zhuyuan Village on the right bank of the Chongjiang River through two 3.0km long inlet tunnels and a 0.8km inlet culvert. The water is then pumped to the outlet pool connected to the Xianglushan Tunnel inlet through the underground pumping station. The highest water level of the effluent pool is 2035.25m, the lowest operating water level of the Jinsha River is 1816.09m, and the maximum net lift for water lifting is 219.16m.
The underground pump station is equipped with a total of 12 centrifugal water pump units, with a single capacity of 40000 kilowatts and a total installed capacity of 480000 kilowatts. During the operation period, 10 units are in operation and 2 units are on standby. At the same time, in order to ensure the normal operation of the underground pumping station, supporting facilities such as transportation, ventilation, power supply, and drainage have been set up. The water source project area has a total of 95 tunnels with a total length of about 24km and a total excavation volume of about 1.46 million cubic meters.
Excavation image of the main pump room of the underground pumping station
The underground pumping station of the water source project has three world records: the world's largest underground pumping station, the world's largest single centrifugal pump capacity for the pumping station, and the world's largest total installed capacity for the pumping station. The excavation scale of the main pump room of the underground pump station is 217m (length) x 23.4m (width) x 48m (height), with a total excavation volume of about 240000 m3. It is divided into 7 layers for excavation. The excavation of the middle guide tunnel started in April 2021 and lasted for 700 days. The excavation, including two collection wells, was completed on March 30, 2023.
As of March 30, 2023, 98.5% of the excavation and support for the underground pumping station system of the water source project have been completed, and the remaining two water outlet shafts will be fully connected by August 2023.
Since the excavation and construction of the underground pump station, the on-site technical personnel of Changjiang Design Group have overcome the impact of the epidemic, faced various difficulties, actively communicated with all parties, provided sincere services, and ensured the quality and progress of on-site construction. During this period, the leaders were on duty at the site, and technical personnel took turns to carry out design service work on site. The specialties were closely integrated, tracking the progress of construction and guiding on-site construction.
The Shigu Project Department of the Group has organized multiple technical exchange meetings to communicate and exchange technical issues with participating units, conduct technical discussions, repeatedly study and discuss various geological problems that may arise during the construction process, and provide on-site dynamic design. Timely special reports and design notices have been issued, and various problems such as seepage, block formation, and karst have been effectively addressed and solved, ensuring the smooth progress of project construction!
