On April 28, with the successful pouring of the structural concrete of Section 3# of the middle pier of the first warehouse lock chamber of the Pinglu Canal Youth Hub, the largest water-saving lock under construction in China, the Pinglu Canal Youth Hub officially entered the construction stage of the main structure of the lock, and at the same time marked that the three hubs of the key control project of the Pinglu Canal have fully entered a new stage of the main construction of the lock.
The Youth Hub is the most downstream cascade among the three cascades planned for the Pinglu Canal, with the main construction contents of double-line locks, flood gates, power stations, connecting dams and fish passages, and the navigable buildings are the largest water-saving locks under construction in China. The total concrete volume of the main body of the Youth Hub Ship Lock is about 760,000 cubic meters, the first warehouse pouring warehouse surface is -15.7 meters to -12.7 meters in the middle wall section of the 3# lock chamber section, the pouring height is 3 meters, and the C30 temperature control three-level with corrosion-resistant concrete is used, and the total pouring volume is 1705 cubic meters.
The Youth Hub is the key point of the Pinglu Canal to the river and the sea, and the seawater upstream and the frequent changes in the water level in the area will cause the hub lock structure to be eroded by chloride ions, and the durability and corrosion resistance of concrete have become key technical problems. The construction management team composed of Pinglu Canal Group and Yellow River Survey, Design, Planning and Research Institute Co., Ltd., Guangxi Bagui Engineering Supervision and Consulting Co., Ltd., CCCC Fourth Harbor Bureau and other participating units adhered to the construction of science and technology to empower the construction of the canal, formulated more than 10 "formulas" for concrete within 5 months, carried out nearly 200 sets of tests, more than 600 test block tests, and carried out a complete set of technologies with more than 100 years of long-life concrete and high durability with top universities and research institutes in China. Research on the functional design of large-volume concrete and intelligent temperature control technology, design and optimize the mix ratio of large-volume concrete, add anti-erosion inhibitors to concrete materials, effectively improve the durability and corrosion resistance of concrete, solve the durability problem of concrete in the brackish and freshwater environment of the youth hub, and through model test research and effect analysis, take engineering measures such as arranging salty pits to effectively suppress the upstream impact of saltwater, and go all out to build high-quality projects, green projects and clean projects.
In view of the technical difficulties and high quality requirements of large-volume concrete temperature control and cracking control, the construction management team built a pre-cooled concrete intelligent environmental protection mixing station with an actual production of 138,600 cubic meters per month, and at the same time equipped with a smart dispatching control center, the introduction of concrete intelligent temperature control system, and the construction process of air-cooled + flake ice + cooling water concrete pre-cooling to realize the whole process of concrete and automatic temperature monitoring, and ensure that the pouring temperature of the concrete strong constraint area is not higher than 16 °C. The design index of the weak confinement zone does not exceed 18°C and the free zone does not exceed 20°C.
Since the start of construction of the Pinglu Canal, the construction management team of the Pinglu Canal has adhered to high-standard design, high-quality construction, high-tech support, high reliability and safety in accordance with the general construction plan of "connecting the river to the sea, overall planning, one-time completion and system operation", and has built high-quality projects with "four first-class", green projects with "four optimals", and clean projects with "three excellent".
Up to now, more than 19,500 people have built the Pinglu Canal, invested more than 6,800 sets of large-scale machinery and equipment, and completed about 196 million cubic meters of earth and stone excavation. In the next step, the Pinglu Canal construction management team will firmly anchor the annual tasks and the completion of navigation goals, promote the construction of the Pinglu Canal with high standards, high quality and high efficiency, and make due contributions to the high-level construction of a new land-sea corridor in the west and the construction of a magnificent Guangxi in the new era.
Contributed by Pinglu Canal Group