Millimeter-level closure! At 10:58 a.m. on February 9, with the hoisting of the final steel box arch segment into place, the main arch of the 2,611-meter Huihe Grand Bridge—a key node project of the Guzhen-Bengbu Expressway in Bengbu—achieved precise closure with millimeter-level error, laying a solid foundation for the full bridge connection and the 2021 opening of the entire line to traffic. Once complete, the drive from Guzhen to Bengbu will be shortened by 40 minutes, and Guzhen will end its history of having no expressway access.

The Gubang Expressway is one of Anhui Province's three major "expressway access for every county" projects and part of the province's planned "Xuzhou-Guzhen-Bengbu" expressway, running entirely within Bengbu. The project starts in Shihu Township, Guzhen County in the north, crosses the Huihe River, and ends at the Hongji interchange in Huaishang District in the south, connecting with the Ningluo Expressway, with a total length of 35.787 kilometers.

As a key node project of the Gubang Expressway, the Huihe Grand Bridge is 2.611 kilometers long, with a 135-meter main span, and is the first steel box composite girder tied-arch bridge on an expressway in Anhui Province. The bridge's superstructure is a basket-handle arch bridge with a main arch height of 32.75 meters; the approach bridges use 50-meter simply supported steel plate composite girders and 35-meter continuous steel plate composite girders, imposing high overall technical requirements. To implement the concepts of green environmental protection and sustainable development, the main bridge girders and arch are all made of steel structures, with a total weight of about 2,500 tons; the main arch closure segment required assembly and welding in the air more than 50 meters above the water surface, involving high safety risks and great construction difficulty.

Since the first pile foundation was driven for the Huihe Grand Bridge in February 2020, the builders have overcome the impacts of the pandemic, floods and many other factors, mobilized all resources, and worked day and night at the bridge site, advancing the project well and quickly. They deeply practiced the "Anhui Precision, Quality Huidao" construction philosophy, controlling installation error to the millimeter level—just 2 millimeters at the smallest—ensuring that the bridge construction maintained strong momentum and quality amid epidemic prevention and control and surging floods.

With the bridge closure, construction of the entire Gubang Expressway has entered an accelerated phase. As of now, the bridge has completed 88% of its overall progress. During the Spring Festival, more than 500 project builders responded to the call to stay put for the holiday and remain on duty, ensuring completion of bridge deck paving by the end of March and full connection of the bridge.

The Huihe Grand Bridge on the Gubang Expressway achieves millimeter-level closure.