At midnight on January 16, with the completion of the final pour of concrete, the Shiliang River double-track super major bridge on the Chongqing–Qianjiang section of the Chongqing–Hunan High-Speed Railway was successfully joined across its full length.

Yang Yitai, head of bridge engineering for the Chongqing–Qianjiang Railway at China Railway Eryuan Engineering Group (CREEC), explained that the construction conditions for the Shiliang River double-track super major bridge are highly complex, as it successively crosses the G65 Baotou–Maoming Expressway, National Highway G353, Provincial Highway S411, the Wulong District industrial park road, and the Shiliang River, while connecting the Chenjiazuiyuan Tunnel and the Guihuayuan Tunnel at either end.

The bridge has a total length of 936.05 meters, comprising 18 spans and 19 piers and abutments. To reduce the maintenance and repair costs of continuously welded track and to avoid installing rail expansion joints for ballastless track, the design team, after multiple rounds of verification, adopted a 2×120-meter prestressed reinforced concrete T-frame continuous girder for Pier No. 4 of the main bridge. This is currently the largest-span prestressed reinforced concrete T-frame continuous girder under construction for a high-speed railway in China. At the same time, the main pier adopts a hollow pier with no longitudinal batter and transverse batter, standing 113.4 meters high, which is also the tallest pier on the entire line.

Shi Lei, project manager of the Chongqing–Qianjiang Section 8 bid of China Railway Seventh Group, explained that since pile foundation construction began in August 2020 for the Shiliang River double-track super major bridge, construction personnel have overcome the difficulty of forming pile holes in complex geology. In response to the unique local geological conditions, they selected, through comprehensive comparative analysis, a drilling method combining "percussion drilling + rotary drilling," which greatly improved construction efficiency while ensuring hole-forming quality and safeguarding pile quality.

"To ensure the construction quality of the mass concrete for the pile cap, we installed an intelligent temperature monitoring system before concrete pouring to monitor temperature changes in real time and carry out curing operations promptly," Shi Lei said. In response to the challenges of construction safety and curing for the 113.4-meter-high pier, construction personnel adopted the currently advanced domestic hydraulic climbing formwork technology, strengthened safety protection measures for the working platform, reduced the handling and turnover of formwork, and introduced an intelligent spray curing system for the pier body that automatically controls the curing cycle, thereby ensuring project quality.

It is understood that the T-frame continuous girder of Pier No. 4 is the controlling works of the entire bridge, with a height of 129.635 meters from the ground to the bridge deck. Safety monitoring during the cantilever form traveler construction of the large-span continuous girder is a key focus of the bridge construction. During construction, technical personnel used science and technology to ensure safety by installing sensors on the main load-bearing parts of the form traveler and transmitting different types of signals to acquisition modules, building an intelligent safety monitoring system for acquisition, communication, monitoring, and early warning. At the same time, real-time monitoring via a mobile phone APP ensured the safety of the continuous girder form traveler construction.

Yang Zhiyong, commander of the Wulong Headquarters of the Chongqing–Qianjiang Railway Co., Ltd., explained that in response to the characteristics of the Shiliang River double-track super major bridge, such as its high piers and large spans, the construction unit established the "Hongyue" Employee Innovation Studio. Research projects were initiated on key construction technologies for high-speed railway T-shaped rigid frame bridges with high piers and large spans, covering issues such as mass concrete construction, BIM technology application, high-pier concrete pouring, cantilever construction and traveling state control of form travelers, safety monitoring of form traveler movement, reasonable concrete pouring techniques for Block No. 0, and later-stage bridge settlement. Scientific research activities were also carried out on intelligent control techniques and methods for movable scaffolding system simply supported girder construction based on BIM technology. To date, the project has completed summaries of 2 research topics, obtained 9 invention patent certificates and 6 utility model patent certificates, been granted 3 provincial- and ministerial-level construction methods, published 4 papers, and obtained 1 overseas patent.

The Chongqing–Qianjiang section of the Chongqing–Hunan High-Speed Railway is an important component of the Xiamen–Chongqing corridor within the "eight vertical and eight horizontal" high-speed railway network in China's Medium- and Long-Term Railway Network Plan. Once the project is completed, travel time from Qianjiang to the central urban area will be shortened from the current 4 hours to less than 1 hour, greatly improving travel conditions for residents along the line. By then, it will further strengthen mutual connections between the areas along the line and economically developed regions such as the West Coast Economic Zone of the Taiwan Strait and the urban agglomerations of the middle reaches of the Yangtze River. It is of great significance for integrating tourism resources along the line, accelerating the development of the "greater tourism economy" in the areas along the line, and promoting the rapid socioeconomic development of the region.