Completed Chaizhuang Sluice Gate on the Xiaoqing River

　　On May 30, with the installation of the final gate and hoist completed, the Chaizhuang Sluice Gate of Section I of the Shandong Xiaoqing River Navigation Restoration Project, constructed by China Railway 25th Bureau Group, was successfully completed, marking the completion and commissioning of the first sluice gate in the Xiaoqing River navigation restoration project.

　　Section I of the Xiaoqing River navigation restoration project undertaken by China Railway 25th Bureau Group has a total length of 29.34 kilometers, including 23.34 kilometers in the Jinan section and 6 kilometers in the Zouping section of Binzhou. The main construction content includes earthwork excavation, reconstruction of 13 bridges, relocation and construction of one Chaizhuang Sluice Gate, construction of one navigation channel maintenance base and public anchorage, and renovation of two inverted siphons, 31 pumping irrigation stations, and 53 culvert gates.

　　"The relocated and reconstructed Chaizhuang Sluice Gate is the starting point of the Xiaoqing River navigation restoration project. It mainly undertakes functions such as flood regulation, irrigation, waterlogging control, and navigation on the Xiaoqing River. It is the first sluice gate for navigation from the Xiaoqing River to the sea and also the first defense line of the entire Xiaoqing River flood control emergency project, bearing on the safety of life and property of 27 million people in five cities along the route," introduced Yang Zhiwen, manager of the Xiaoqing River navigation restoration project of China Railway 25th Bureau Group. The hub project consists of an upstream connecting section, gate chamber section, stilling basin section, and downstream connecting section. It uses gate opening and closing to regulate upstream water level and discharge flow, meeting the needs of water distribution or flow cutoff for the next-level channel and channel maintenance behind the gate. It is also a key control project along the entire line.

Completed Chaizhuang Sluice Gate on the Xiaoqing River

　　"During construction, 17-meter-high large formwork had to be erected on the original river channel of the Xiaoqing River. In particular, for the gate piers and second-stage concrete, 430 cubic meters of concrete had to be poured at one time. At the same time, one side of the sluice gate is less than 8 meters from the water supply pipe of the South-to-North Water Diversion Project, placing extremely high demands on construction technology," introduced Yu Xiulong, chief engineer of the project. They held multiple expert review meetings to analyze key and difficult construction points and continuously optimize the construction plan. On the one hand, they adopted the method of a diverted open channel, establishing a 297-meter-long diversion open channel before and after the sluice gate to lead river water to the other side; on the other hand, they arranged 78 dewatering wells around the foundation pit and excavated the original riverbed soil layer 7 meters lower for concrete pouring, equivalent to adding a "waterproof membrane" on top.

　　It is understood that the most important function of the sluice gate is to regulate water level, and gate installation is also one of the key and difficult points of the entire sluice gate project, with extremely high requirements for controlling the verticality and horizontality of embedded parts. In particular, the connection quality between the movable gate and the embedded parts of the fixed gate slot is critical; even a slight gap will cause water leakage through the gate. Since mobilization, the project department has established a QC research group, organized on-site technical personnel to participate in training multiple times, held expert review meetings, continuously optimized the construction plan, strictly controlled every link from raw materials to construction procedures, ensured that gate installation met specification requirements, and guaranteed the construction quality of the sluice gate.

　　At present, the upstream concrete apron, downstream stilling basin, wing wall base slab, wall body, gate base slab, gate piers, gates, bent frames, prefabricated frame bridge slabs, and the first-level rubble masonry slope protection on the downstream right bank of the sluice gate have all been completed. The project is now sprinting toward the "June 30" flood control milestone for completing the inverted siphon.

　　The Xiaoqing River navigation restoration project, running across the five cities of Jinan, Binzhou, Zibo, Weifang, and Dongying in Shandong, is the "No. 1 project" among Shandong Province's key water conservancy projects and an important "horizontal" in the "one vertical and three horizontals" high-grade waterway network planned in Shandong Province's inland waterway layout. It is also the only waterway in Shandong Province at the current stage with conditions for development and utilization of sea-river combined transport, and the first project in the history of Shandong's water transport construction with a one-time investment exceeding 10 billion yuan that can achieve direct sea-river transport. After the entire project is completed, the flood control standard of the main stream and flood diversion channels of the Xiaoqing River will be raised from once in 20 years to once in 50 years, with the Jinan urban section reaching the once-in-100-years standard, effectively protecting the safety of life and property of residents on both banks of the Xiaoqing River.