On July 5, at the construction site of the No. 3 main pier of the Chongqi Highway-Railway Yangtze River Bridge over the north branch of the Yangtze River on the North Yanjiang High-Speed Railway, as the last truckload of concrete was poured into pile hole No. 20, all 76 bored piles of the bridge's south main tower were completed, marking the completion of all pile foundations for both main towers of the Chongqi Highway-Railway Yangtze River Bridge. This is an important milestone in the main structure construction of the project, laying a solid foundation for the next stage of pile cap construction for the main piers.

Yang Hairong, project manager of the First Sub-division of the V Bid Section of the Shanghai-Nanjing Section of the Shanghai-Chongqing-Chengdu High-Speed Railway under China Railway Major Bridge Engineering Group, introduced that the bored piles for Pier No. 3 of the south main tower foundation are designed as 76 friction-type bored piles with a diameter of 2.5 meters, with a maximum designed drilling depth of 130 meters. The bored piles for the No. 3 main tower pier are designed to use approximately 42,000 cubic meters of concrete. The bridge site is located at the mouth of the Yangtze River, where the irregular semi-diurnal tide has high flow velocity, and construction is affected by typhoons, tides, and the seawater environment; the north branch channel of the Yangtze River where it is located is winding, with large variations in water depth, complex water conditions, and strong scouring, presenting construction characteristics such as high difficulty in hole formation and new requirements for equipment.

To ensure the construction quality and efficiency of the No. 3 main pier, the project construction management unit, Shanghai-Hangzhou Passenger Dedicated Line Company, together with the contractor China Railway Major Bridge Engineering Group, scientifically formulated the construction plan and conducted technical and safety briefings in advance. Construction of the bored piles for the No. 3 main pier began at the end of April and was completed in 70 days with 76 bored piles, far ahead of schedule, achieving rapid construction.

The Chongqi Highway-Railway Yangtze River Bridge has a total length of 4.09 kilometers and spans the north branch channel at the mouth of the Yangtze River. It is a double-deck highway-railway bridge: the upper deck carries a two-way six-lane first-class highway with a design speed of 100 km/h, and the lower deck carries a double-track high-speed railway with a design speed of 350 km/h plus a double-track intercity railway with a design speed of 250 km/h. The main navigable span bridge is a cable-stayed bridge with a main span of 400 meters, featuring two towers, two cable planes, and a steel truss composite girder. It is the world's largest-span cable-stayed bridge with two towers and two cable planes for highway-railway dual use with ballastless track. Its main girder adopts a new structure of main truss plus auxiliary truss steel-concrete composite girder, and the highway deck adopts concrete composite slab decks, making it the world's first cable-stayed bridge with an all-steel truss composite girder in which highway concrete slabs participate in the primary structural system.

The North Yanjiang High-Speed Railway is the eastern section of the Shanghai-Chongqing-Chengdu High-Speed Railway and an important component of the Yanjiang high-speed railway corridor of the national "Eight Vertical and Eight Horizontal" high-speed railway network. Once completed, it will establish a new rapid corridor among the Shanghai metropolitan area, the Nanjing metropolitan area, and the Hefei metropolitan area, which is of great significance for optimizing the layout of the railway network along the Yangtze River, serving the coordinated development of the Yangtze River Economic Belt, and promoting high-quality integrated development of the Yangtze River Delta.