A photo taken on May 5 shows the girder erection construction site of the Chengdu-Chongqing Middle Line High-speed Railway. Photo: Xinhua

　　The Chengdu-Chongqing Middle Line High-speed Railway, a major transportation link in Southwest China, saw the successful completion of its full box girder erection work on Tuesday, as the final 32-meter-long box girder, weighing about 700 tons, was steadily installed onto the piers of the Jialing River Grand Bridge. This step lays a solid foundation for the project"s early opening and operation, the People"s Daily reported.

　　The construction of the line reflects the improvement of infrastructure and engineering capabilities in China"s central and western regions, a Chinese industry analyst said, noting that it is expected to strengthen regional connectivity, promote the integration of tourism and economic development, and further enhance the level of openness and the urban radiating capacity of inland areas.

　　The Chengdu-Chongqing Middle Line High-speed Railway line starts from Chongqing North Railway Station, runs westward through multiple areas including the Liangjiang New Area, Shapingba district, Dazu district, and city of Ziyang in Sichuan Province, and connects to Chengdu Station. The main line has a total length of 292 kilometers, with a designed speed of 350 kilometers per hour, and certain sections have provisions for speed upgrades.

　　Box girders are the key load-bearing components of a bridge, carrying all loads from the bridge deck and forming the stable main support structure of the high-speed railway bridge once ballastless track construction and track laying are completed, the report said, citing Wang Gang, a manager for the Chengdu-Chongqing Middle Line High-speed Railway project at the China Railway 12th Bureau Group.