On August 17, the “Shanhe” shield machine, with a cutting diameter of 17.5 meters, successfully broke through at the Huanggang Road Yellow River Tunnel in Jinan, the capital of East China’s Shandong Province, marking the completion of the world’s largest diameter underwater shield tunnel.
Constructed by China Railway 14th Bureau Group Corporation Limited under China Railway Construction Corporation Limited, the project represents a milestone in China’s underwater tunnel engineering.
The Huanggang Road Yellow River Tunnel spans approximately 5.75 kilometers and is designed for speeds of up to 60 km/h. It is China’s first single-bore, double-deck shield tunnel crossing the Yellow River. The project team developed and applied dual-line hydraulic rock-grinding devices to overcome challenges posed by difficult geology, achieving a continuous 3.3-kilometer excavation under the river without replacing the cutterhead.
Panoramic view of the Huanggang Road Yellow River Tunnel [Photo/sasac.gov.cn]
The “Shanhe” shield machine excavates an area of 240 square meters — larger than half a standard basketball court. Each ring of excavation generates 1,200 cubic meters of slurry, presenting significant handling challenges. The team pioneered a combined “flocculation + thickening + filter-press” process, improving slurry treatment efficiency, enabling full recycling of tailwater, and achieving zero external discharge.
A view of the Huanggang Road Yellow River Tunnel [Photo/sasac.gov.cn]
The project team has tackled 28 major technical challenges, achieving a record daily advance of 18 meters and a monthly progress of 426 meters. The complete technical system for 17-meter-class shield tunneling established by the team enhances China’s capability in constructing ultra-large-diameter shield tunnels and further solidifies the country’s leading position in this field.
(Executive editor: Wang Ruoting)
