On March 17, 2026, with the completion of the last cast-in-place lane slab pouring Jinan Urban Construction Group Co., Ltd.、China Railway 14th Bureau Group Co., Ltd. The upper lane slab of the Yellow River Tunnel on Huanggang Road in Jinan, which was constructed, has been fully completed, marking the official achievement of double-layer connection of the world's largest diameter underwater shield tunnel.

As a key project in Jinan to implement the national strategy of ecological protection and high-quality development in the Yellow River Basin, the Huanggang Road Yellow River Tunnel has a total length of about 5.75 kilometers, including a shield section of about 3.3 kilometers, which is excavated using the Shanhe shield machine with a diameter of 17.5 meters. The tunnel adopts a single hole double-layer design, with a total of six lanes on the upper and lower layers, and a designed speed of 60 kilometers per hour. It is the first single hole double-layer shield tunnel in China to pass through the Yellow River.

After the completion of the shield tunnel, the construction of the internal secondary structure will proceed synchronously. The upper lane board is located in the middle of the tunnel, dividing the single hole space into two layers. It is not only the load-bearing structure for upper level vehicle traffic, but also provides support for subsequent processes such as pipeline laying and ventilation equipment installation. The lane slab adopts cast-in-place concrete technology, with a large construction scale and high technical requirements.

To overcome construction difficulties, the project team innovatively utilized 12 hydraulic integral walking trolleys, and achieved integrated operations of template assembly, displacement, positioning, and concrete pouring through modular design and autonomous walking system. Multiple trolleys synchronously carry out segmented construction, forming a flow operation mode for steel bar binding, formwork installation, pouring and curing, greatly improving construction efficiency. Keywords: Huanggang Road, Yellow River Tunnel, Double layer Connection, Single hole Double layer

After the completion and opening of the tunnel, it will effectively connect the main urban area of Jinan with the starting area for the conversion of old and new kinetic energy, and the commuting time between the two sides will be reduced from 40 minutes to 4 minutes. This is of great significance for enhancing the primacy and radiating driving capacity of Jinan as the provincial capital city, deepening the implementation of the Yellow River national strategy, and promoting Jinan's transition from the Daming Lake era to the Yellow River era.Editor/Gong Ziwei