On May 10, with the successful insertion of the final closure segment, the steel pipe arch ribs of the Lami River Bridge, constructed by Guizhou Transportation Construction Group, were smoothly closed. The bridge is the widest asymmetric concrete-filled steel tube arch bridge among expressways under construction in China, laying a solid foundation for the full opening of the Guiping Expressway (Guiyang–Pingtang).

The Lami River Bridge is located in Zhemi Town, Pingtang County, crossing the Hongshui River system of the Pearl River Basin. It is a major difficult and controlling project of the Guiping Expressway. The bridge is a two-way six-lane half-through and through asymmetric steel pipe arch bridge, with a total length of 206 meters, a main span of 176 meters, a deck about 106 meters above the water surface, and a width of 40.8 meters. The entire bridge has 18 arch rib hoisting segments and 7 cross braces, with a maximum hoisting weight of 104 tons.

It is understood that the arch abutments on both banks of the Lami River Bridge are located on steep mountains. Facing bottleneck problems such as site constraints, heavy arch rib segments, large lifting and swing angles, high friction coefficient of the cable saddle slideway lateral movement, and high hoisting precision, the project department actively strengthened process supervision, strictly controlled construction techniques, refined installation steps, and focused on overcoming key technical problems.

"Because there are no hoisting conditions below the Lami River Bridge, the arch ribs were hoisted from on the bridge, and the cable towers were arranged independently upstream and downstream. The arch transport vehicle was blocked by the tower frame, so the arch ribs could not be transported directly to the vertical lifting area of the cable hoisting system; instead, 'swing shifting' was needed to swing the arch ribs into the vertical lifting area of the cable hoisting system. Therefore, during arch rib hoisting, the project department for the first time adopted a single-side asymmetric hoisting technique. Through the innovative technique of 'load lateral movement + swing shifting,' collisions between hoisting and buckle cables were effectively avoided, solving the problems of limited site space and excessive arch rib load," Kuang Huajiang, project manager of the Guiping 18 bid section of the Road and Bridge Group under Guizhou Transportation Construction Group, told reporters.

In addition, the project department also used Beidou sensors and the Beidou satellite positioning system to conduct intelligent monitoring through a data acquisition and transmission system, precisely carrying out dynamic real-time monitoring of key parameters such as buckle and back cable forces, load-bearing, lifting, and traction cable forces. Based on the monitoring data, the elevation difference and spacing of the arch rib closure opening were adjusted to ensure 'zero error' precise closure.

After the Guiping Expressway is completed, the drive from Guiyang to Guangxi will be shortened from the original 3.5 hours to 2.5 hours. It will become another new sea outlet corridor in the greater southwestern region and is of great significance for promoting the economic and social integration and development of Sichuan, Guizhou, and Guangxi.