After 60 continuous hours of concrete pouring, the construction of the world's largest caisson for a highway project, the Hannan Yangtze River Bridge's south anchorage caisson, was completed in Wuhan, Central China's Hubei province, last week, according to its builders.

This milestone marks the completion of the first stage of heightening for the caisson, leading up to the next phase of sinking. The project is funded by Wuhan Urban Development Group and constructed by Road & Bridge International Co Ltd, a subsidiary of State-owned China Communications Construction Co.

The Hannan Yangtze River Bridge is set to be the 13th bridge over the Yangtze River in Wuhan and a crucial part of the city's metropolitan area ring expressway. The bridge design features a main span of 1,600 meters with a dual-tower, single-span steel box girder suspension design, according to a statement from Road & Bridge International.

It is designed to be the largest span, dual-main-cable, eight-lane suspension bridge in Hubei province, accommodating speeds of up to 120 kilometers per hour.

Facing challenges such as massive concrete volume, prolonged continuous work, large construction area, high safety risks and temperature fluctuations, the construction team adopted innovative solutions, according to the statement.

These included a self-developed foundation reinforcement technique for alluvial soil and an efficient cantilever formwork system, as well as a smart monitoring system to ensure structural safety and stability during construction.

As a key transportation infrastructure project, the Hannan Yangtze River Bridge will enhance regional transportation networks, optimize Yangtze River crossings, and boost integrated development in the Wuhan Metropolitan Area upon completion, said Road & Bridge International.