The Xingyi Yangtze River Bridge has a total length of 2,343 meters and a main span of 1,120 meters, making it the longest-span double-deck suspension bridge on the upper reaches of the Yangtze River. The pile foundation construction for the main pier on the north bank of the bridge can be described as "surgery on a cliff": the construction area is located below a Class 7 high and steep slope on the north bank of the Yangtze River, and the working conditions are extremely harsh. The main pier pile foundation is designed with a diameter of 3.0 meters and a pile length of 70 meters; the concrete volume of a single pile exceeds 520 cubic meters, and the reinforcement cage weighs 56 tons. The project faces multiple challenges, including great hole depth, large pile diameter, high single-pour volume, heavy reinforcement cages, and an extremely narrow construction site.

Faced with these numerous difficulties, the project team adhered to scientific overall planning and precise measures. Lightweight concrete filling was used to complete the construction platform, laying a solid "operating deck" for construction work; the operation plan of "excavate and transport immediately, dry-wet zoning" was implemented to efficiently solve the problems of earthwork disposal and environmental protection. At the same time, rotary drilling rigs were used for layered drilling, with strict control of hole-forming quality; a 150-ton crawler crane, together with special lifting tools, was used to hoist the 56-ton reinforcement cage in sections and steadily "implant" it into place; the tremie method was adopted for continuous pouring, with strict control of the concrete mix ratio, slump, and tremie pipe embedment depth to ensure pile quality. A series of measures effectively guaranteed the safe, high-quality, and efficient progress of pile foundation construction under complex conditions.

Next, the project will continue to maintain its攻坚 (assault) momentum, advance the batch construction of the main pier pile foundations at full speed, strictly control safety, quality, and schedule, ensure the efficient achievement of node targets, and accelerate project construction to improve speed and efficiency.

Source: Sichuan Road & Bridge