Shanghai Chongqi Gongiron Yangtze River Bridge has made new progress

China Railway Shanghai Bureau Group Co., LTD., today (June 29) at 3:18 am, the Shanghai to Nanjing to Hefei high-speed railway Chongqi Railway Bridge north of the main tower of the 76 piles have been completed, the main construction of the bridge has made progress.

At around 2 p.m. on the 28th, at the construction site of the No. 4 main pier of the Chongqigongtie Yangtze River Bridge on the northern branch of the Yangtze River, the concrete pouring of the last pile foundation of the No. 4 main pier officially began, only to see a concrete mixing truck parked steadily beside the steel protection cylinder of the pile foundation and dumped concrete into the hopper under the operation of the construction personnel. After this concrete mixer truck is dumped, the next concrete mixer truck follows. At 3:18 am on the 29th, with the last car of concrete poured into the pile hole, it also marked the completion of 76 pile foundations of the north main tower of Chongqigong Railway Yangtze River Bridge on the Shanghai-Nanjing to Hefei high-speed railway, and the main construction of the bridge has made progress.

The main beam of the main navigable passage bridge of Chongqi Railway Yangtze River Bridge adopts the new structure of steel-concrete composite beams with main girder and auxiliary girder, and the highway bridge decks are all made of concrete composite girder, which is the first highway concrete slab cable-stayed bridge in the world to participate in the first system of stress, and is also the control node project of high-speed railway from Shanghai to Nanjing to Hefei, with a total length of 4.09 kilometers, across the north branch channel of the Yangtze River estuary. Its structure is a double-layer arrangement of dual-purpose bridge, the upper level is a two-way 6-lane, 100 km/h, the first level of highway, the lower level is a 350 km/h dual-line high-speed railway + 250 km/h dual-line intercity railway. The bridge is divided into main navigable pass bridge, non-navigable pass bridge, south and north shore combined approach bridge, south and north shore single railway approach bridge; Among them, the main navigable pass bridge is the 400-meter double tower double cable plane steel truss combined girder cable-stayed bridge, which is the world's largest span double tower double cable plane public-iron dual-purpose ballastless track cable-stayed bridge, of which pier No. 3 and pier No. 4 are the south main tower and the north main tower respectively.

76 pile group foundations with a diameter of 2.5 meters are used in the design of the bridge's No. 4 main pier. The overall layout is a mixed arrangement like a blossom. The maximum pile length is 120 meters, the drilling depth is 142 meters, and the designed concrete square volume of a single pile is 618 cubic meters. Because the bridge is located in the estuary of the lower reaches of the Yangtze River, the geology of the drilling area is silty clay, silty sand and silty clay. The thickness of the silty clay stratum is about 20 meters, which has the characteristics of difficult hole formation, new equipment requirements and high environmental protection requirements.

In order to ensure the construction quality of the No. 4 main pier, the construction unit has scientifically formulated the construction plan, actively deployed labor resources, disclosed the technology and safety in advance, researched and developed the intelligent post-grouting technology of the pile bottom and pile side, adopted 5G technology to monitor and control the grouting volume, mix ratio, flow rate, pressure and other indicators in real time, and realized the network, digital and visual monitoring of the grouting process. So as to achieve the purpose of precise control of grouting quantity and precision control of grouting effect.

It is reported that the Shanghai-Nanjing to Hefei high-speed railway is the eastern section of the Shanghai-Chongqing-Chengdu high-speed railway line, the national "eight vertical and eight horizontal" high-speed railway network along the river high-speed rail channel is an important part of the Yangtze River channel main network passenger flow, coastal and Beijing-Shanghai channel part of the passenger flow through Shanghai transport. After the completion of the project, a new fast channel will be built between the Shanghai metropolitan area, the Nanjing metropolitan area and the Hefei metropolitan area, which is of great significance for optimizing the railway network layout along the Yangtze River region, serving the coordinated development of the Yangtze River Economic Belt, and promoting the high-quality integrated development of the Yangtze River Delta.