Three Decades of Service, Now Reborn for the Road Ahead
Three Decades of Service, Now Reborn for the Road Ahead
— Maintenance Project of Kunming Yuantong Bridge Successfully Completed
Recently, the maintenance project of Yuantong Bridge, jointly designed by Yunnan Institute and the Third Institute, has been successfully completed, officially restoring traffic. As a critical transportation link connecting multiple districts of Kunming’s urban core, Yuantong Bridge—having witnessed 33 years of the "City of Spring’s" evolution—has now achieved a significant rebirth .
During implementation, Yunnan Institute and the Third Institute formed a joint project team, collaborating closely with design representatives stationed on-site to ensure safe, orderly, high-standard, and high-quality bridge maintenance . Their technical expertise and service earned unanimous praise from all participating parties, enhancing the institute’s brand in Kunming and laying a solid foundation for deeper local market engagement.
The Yuantong Bridge maintenance project was not merely a repair task but a tribute to Kunming’s urban history. Every tightened bolt and replaced cable carries aspirations for the city’s future, embodies the unique craftsmanship of the institute’s bridge designers, and demonstrates its commitment to the southwestern market.
Project Overview
Yuantong Bridge, completed in 1991, has served for 33 years. It is Kunming’s first single-pylon, single-cable-plane cable-stayed bridge and a landmark spanning the Panlong River . The bridge adopts a single-pylon, single-cable-plane system with integrated pylon, girder, and pier. The pylon is concrete, the main girder a reinforced concrete box girder, and the stay cables are arranged symmetrically in a harp pattern. Eleven cable pairs form one cable plane, with two cables per pair, totaling 44 stay cables . The bridge spans 253.75 meters with a deck width of 24.5 meters.
Over the past decade, four inspections revealed six major defects:
Stay cables: Deteriorating cable force due to prolonged service .
Main girder: Multiple cracks, increasing annually.
Expansion joints: Blocked and damaged.
Deck pavement: Poor condition with transverse penetrating cracks.
Drainage holes: Partially blocked by sediment.
Aesthetic degradation: Coating peeling on the pylon, water seepage, and whitish stains on surfaces.
The maintenance addressed these issues through:
Sealing cracks.
Replacing expansion joints at both ends.
Reinforcing severely damaged base layers and repaving the asphalt surface.
Clearing drainage holes.
Implementing landscape enhancements.
