On June 7, the pile foundation reinforcement project of the Longmen Yellow River Grand Bridge on the Houma-Yumen section of the G5 Beijing-Kunming Expressway completed the concrete pouring of the last pile foundation, marking the full and on-schedule completion of the special maintenance project for the Longmen Yellow River Grand Bridge.

The pile foundation reinforcement project is an important component of the special maintenance project for the Longmen Yellow River Grand Bridge. This project is the first pile foundation reinforcement project for a Yellow River bridge in Shanxi Province, and also the first application of UHPC (ultra-high performance concrete) in the field of bridge pile foundation reinforcement. The smooth implementation of the project has accumulated detailed experimental data and transferable construction experience for similar bridge pile foundation reinforcement projects across the province.

During construction, the project team overcame multiple interwoven challenges, including great difficulty in multi-party coordination, a limited effective construction window, and the adverse conditions of being located in the Yellow River channel with complex water conditions and the arrival of the flood season. The participating units scientifically coordinated the construction plan, optimized the operation scheme, and innovatively adopted the four-character working method of "probe, bypass, dredge, and tow," successfully solving the problem of water-land material transportation. In response to the risks of in-water construction, the site employed multiple techniques such as immersed-tube dewatering within the cofferdam, shallow excavation at the cofferdam bottom, and deep pressing of the bottom formwork, effectively lowering the cofferdam water level. While greatly improving operational efficiency, this achieved throughout the "five zeros" goal for in-water construction: zero accidents, zero hidden dangers, zero emergencies, zero violations, and zero errors.

Up to now, all three works included in the special maintenance project for the Longmen Yellow River Grand Bridge—repair and protection of the PE sheathing of the bridge's stay cables, repair of routine bridge defects, and UHPC reinforcement of pile foundations—have been completed. In addition, the research topic "Key Technology for Local Reinforcement of Thin-Layer UHPC for Underwater Damage to Bridge Substructure," jointly carried out by Shanxi Communications Holding Yuncheng Company and Shanxi Transportation New Technology Development Co., Ltd. based on this project, has been preliminarily completed. Going forward, the application value of the new technology will continue to be explored, efforts will be made to promote the transformation and utilization of results, and continuous support will be provided for the quality upgrading of bridge maintenance technology.

(Source: Yuncheng Daily)