At 5 a.m. on December 25, as the last truckload of concrete was slowly pumped in, the main line bridge of the Yong'an Multi-Track Extra-Large Bridge, constructed by the Guinan HSR Section 6 project of China Railway 11th Bureau Group, was successfully poured and completed, marking the full connection of the main line bridges in this section.

It is understood that the Yong'an Multi-Track Extra-Large Bridge is an important connection point between the two extra-long high-risk tunnels at Yongshun and Du'an on the Guinan HSR, as well as Yong'an Township Station, and is also a key and difficult control project in this section. As a multi-track extra-large bridge in a karst landform area, the bridge has an extremely thick overburden layer, locally reaching 60 to 80 meters; its cave encounter rate is 44%, and some bridge piers have bead-like karst development, making pile foundation hole formation extremely difficult. The project adopted reverse circulation drilling rigs to drill to a depth of about 50 meters before switching to percussion drilling; after repeated flushing and filling, all pile foundation construction was completed over two and a half years.

The Yong'an Multi-Track Extra-Large Bridge is 805.4 meters long and has 23 spans in total, with 291 designed pile foundations, the longest of which is 94.5 meters. As a station bridge, its girder structure is complex, with cast-in-place single-track simply supported girders, double-track simply supported girders, single-track continuous girders, double-track continuous girders, and multi-track continuous girders arranged in an interlaced manner, making construction extremely difficult. In response, the project department scientifically formulated support construction management measures, comprehensively optimized resource allocation before construction started, increased investment in manpower, materials, and mechanized equipment, and carried out simultaneous construction operations across five work faces; during the process, it vigorously conducted support construction safety inspections, strictly implemented the "chief engineer, department head, and management team leader inspection reporting system" for key procedures, and tracked measurement data throughout the pouring process to ensure support safety and quality assurance.

Since the beginning of this year, Section 6 has organized construction scientifically and successively overcome multiple key and difficult points, smoothly achieving full bridge connection and laying a solid foundation for the completion of the entire section's tasks on schedule and track laying.

Up to now, the main works of the Yong'an Multi-Track Extra-Large Bridge, Xiangfu Bridge, and Anhua Bridge under the responsibility of the Guinan HSR Section 6 project department have all been completed.

The Guinan HSR runs through northwestern Guangxi and southeastern Guizhou. It is the first high-speed railway in Guangxi designed for a speed of 350 kilometers per hour, and is also an important part of the new north-south land corridor connecting the "Belt and Road." It is of great significance for Guangxi to advance the construction of the New Western Land-Sea Corridor and accelerate the establishment of a new open development pattern of "southward connection, northward linkage, eastward integration, and westward cooperation." The entire line is expected to open to traffic by the end of 2023, when travel time from Nanning to Guiyang will be shortened to more than two hours.