Builders of the 2,440-kilometer Beijing-Kunming High-Speed Railway Corridor, one of the nation's "eight verticals and eight horizontals" in the HSR network, made a new breakthrough after they finished cement pouring on top of a main pier of the Tuojiang super bridge in Sichuan province.

The Tuojiang Super Bridge will stand on two main piers, No 40 and No 41, with a total length of 2,613.3 meters. Cement pouring was completed on Sunday for the two blocks on the No 41 pier on the south bank of Tuojiang River, an upper tributary of the Yangtze River, the country's longest river.

After more than 10 hours of intense work, builders from China Railway No 4 Engineering Group Co Ltd (CREC4) celebrated their successful work on the two blocks, ushering in the official construction of the overhanging beam of the super bridge.

CREC4 staffer Zhang Furong said the main span will be composed of three sections of 124 meters north of the No 40 pier on the north bank of the river, 240 meters between the two main piers and another 124 meters south of the No 41 pier.

The Tuojiang super bridge is the most difficult bridge to construct for the Chongqing-Kunming section. It is located in the suburbs of Luzhou and its double-column V-shaped bridge tower on its two main piers is the first of its kind to be built in China, Zhang said.

CREC4 is building the super bridge, whose main span in three sections is also the longest continuous beam on the Chongqing-Kunming section, he said, adding the bridge, which began construction early last year, will end construction by January next year.

Yin Ze, chief engineer of the project from CREC4, said the two blocks on pier 41 standing some 75 meters up from the ground, are difficult to handle. A huge amount of cement was needed, with high prestressing demand in addition to difficulties in tying off the steel bars.

The concrete volume covering some 2,000 square meters and running up to 13 meters in height is immense, he said. It required extremely high-stress performance and installation accuracy in the overall load-bearing brackets.