On April 1, the drilling construction of the pile foundations for both main piers of the main bridge of the Changsha Xiangjiang Railway Grand Bridge was fully completed, marking a breakthrough in this key control project of the Changsha-Ganzhou High-Speed Railway and opening up a favorable situation for subsequent construction. Sunward's rotary drilling rigs SWDM800 and SWDM600, with their outstanding performance, contributed to the efficient and high-quality completion of Pier 138 of the Changsha Xiangjiang Railway Grand Bridge, making them well-deserved "meritorious equipment."

Tackling the "hard bone": drilling deep holes in granite

The main bridge of the Changsha Xiangjiang Railway Grand Bridge has a total length of 768.1 meters and crosses the main navigation channel of the right branch of the Xiangjiang River in a single span. It is the longest-span bridge on the entire Changsha-Ganzhou High-Speed Railway and a key node of the Yuxia Corridor of the national "Eight Vertical and Eight Horizontal" high-speed railway network. Once the project is completed, the train travel time from Changsha to Ganzhou will be reduced from about 4 hours to as fast as 1.5 hours, which is of great significance to the coordinated development of Hunan and Jiangxi provinces and the improvement of the regional road network.

However, the bridge construction was no easy path. The main bridge lies on a straight alignment, and the horizontal distance between the center of the left line and the center of the existing second line of the Shichang Railway is only about 33.67 meters, posing extremely high construction organization difficulty and safety risks. Of particular note is Pier 138 of the main bridge—it is located in the Xiangjiang River, where the overburden is extremely shallow, with only a layer of sand and gravel beneath the riverbed and hard granite formations below. Compared with Pier 137 on the other side, this imposed higher standards on construction precision and process control. At the same time, the Xiangjiang River water area has strict environmental protection requirements, placing high demands on mud treatment and noise control.

Perfect completion in 69 days: Sunward equipment demonstrates its "hardcore" character

Faced with such a "hard bone," the project owner, after multiple comparisons and selections, ultimately chose Sunward's SWDM800 and SWDM600 super-largerotary drilling rigsto participate in the drilling construction of Pier 138 of the main bridge. These two "giants" are designed specifically for deep, large-diameter pile foundation construction in super projects such as super-high-rise buildings, long-span bridges, and high-speed railways and expressways. In actual operation, the high torque and high crowd force of the SWDM800 and SWDM600 cut into granite with strength up to 140 MPa like "steel sharp teeth," crushing it efficiently; the industry's first high-inertia rotary platform braking force enhancement technology and the Sunward Xiangyun intelligent control system provided real-time monitoring, ensuring the precise formation of large-diameter pile holes with a pile depth of 52 meters and a pile diameter of 2.8 meters; after 69 days of continuous effort, the work was successfully completed. This speed won valuable time for subsequent procedures.

"In the main bridge project of the Changsha Xiangjiang Railway Grand Bridge, Sunward's equipment demonstrated Sunward's strength!" said Mr. Jia, the project manager, at the site. He particularly noted that the geological conditions at Pier 138 are very complex, and Sunward's equipment not only "could chew through" high-strength granite but also offered good stability, providing key technical support for the project's progress on schedule.

From major domestic projects such as the Hangzhou Bay Bridge and the Yanji Yangtze River Bridge to "Belt and Road" projects such as the Tarlac-Bamban Bridge in the Philippines, Sunward's super-largerotary drilling rigswith outstanding advantages such as high reliability and high efficiency have repeatedly set construction records under complex geological conditions. The perfect completion of the main pier pile foundation project of the Changsha Xiangjiang Railway Grand Bridge once again confirms Sunward's leading position in the comprehensive field of underground engineering. As the construction of the Changsha-Ganzhou High-Speed Railway advances in full swing, Sunward will continue to contribute "Sunward strength" to the strategy of building a strong transportation country with innovative products and professional services.

Source: Sunward