On December 8, the double-wall steel cofferdam for the pile cap of Pier 77, the first deep-water foundation of the main bridge of the Xijiang River Grand Bridge on the Zhuhai-Zhaoqing High-Speed Railway project, was successfully sealed at the bottom, laying the foundation for subsequent construction of the main tower.

The Xijiang River Grand Bridge is a key project of the Zhuhai-Zhaoqing High-Speed Railway, connecting Yong'an Town and Shapu Town in Dinghu District. The main bridge of the Zhuhai-Zhaoqing High-Speed Railway Xijiang River Grand Bridge, which crosses the Xijiang River, has a total length of 1,307.6 meters, with bridge towers averaging 172 meters in height. It is China's first three-tower composite girder railway cable-stayed bridge. The steel cofferdam for Pier 77, which was sealed at the bottom this time, is located in the main navigation channel of the Xijiang River.

The cofferdam sealed this time is rectangular, 47.1 meters long, 32.1 meters wide and 31.015 meters high, with an area equivalent to three standard basketball courts. The bottom-sealing concrete is 6 meters thick, with a total of more than 6,600 cubic meters of concrete poured.

The Zhuhai-Zhaoqing High-Speed Railway is the first 350 km/h high-speed railway independently invested in, constructed and managed by Guangdong Province. It connects Zhuhai, Jiangmen, Foshan and Zhaoqing, with its main line linking to the planned Pearl River Delta Hub Airport. After the project is completed, the fastest travel time from Zhuhai to Zhaoqing East will be 36 minutes, and major cities in the Pearl River Delta along the line will be connected within one hour.