On April 8, the first pile cap of the Luoze River Grand Bridge, a controlling project of the Chongqing-Kunming High-Speed Railway, was completed with concrete pouring, marking phased progress in the construction of the grand bridge.

　　The Luoze River Grand Bridge is 524.9 meters long and is designed as a double-deck single-track bridge with left and right lines. Its main span crosses the Luoze River, and the terrain on both banks is steep with complex geological conditions. The pile cap of Pier No. 2 of the Luoze River Grand Bridge poured this time is designed to be 43.7 meters long, 21.3 meters wide and 6 meters high, making it the largest pile cap on the Chongqing-Kunming High-Speed Railway line. It was poured with C40 concrete, and the pouring volume, including the first 2-meter section of the pier shaft, exceeded 6,000 cubic meters.

　　To prevent cracks in the pile cap concrete caused by excessive hydration heat, the project department carried out calculation and analysis of hydration heat using software, installed temperature measuring elements and circulating cooling water pipes inside the concrete, and used an intelligent temperature control box to monitor the internal and external temperatures of the concrete in real time. By controlling the inlet temperature, flow rate and circulation duration of the cooling water, the temperature difference between the inside and outside of the concrete was precisely regulated to ensure the construction quality of the pile cap.

　　According to reports, the construction organization of this pile cap was difficult and required high technical standards. All participating personnel of the China Railway Major Bridge Engineering Group's Chongqing-Kunming project department braved difficulties and pressed ahead, adhered to technology first, and focused on optimizing the construction organization plan. The first section of the pier shaft and the pile cap were poured simultaneously in one operation to accelerate construction progress. At the same time, resources such as personnel, machinery and materials were rationally allocated for continuous 24-hour operations to speed up the construction of the pile cap and pier shaft. During pouring, safety, quality and environmental protection were strictly controlled, striving to make it a new model for high-speed railways in western China.