The upper deck of the tunnel, which is located on Huanggang Road, was finished with the pouring of the final cast-in-place roadway slab, reported the Global Times, the state-owned Chinese newspaper.
The tunnel is China's first single-bore, double-deck shield tunnel to pass beneath the Yellow River, an engineer involved in the project told the Global Times. Spanning 5.75 kilometers (around 3.6 miles), the tunnel accommodates six lanes across two levels, with a speed limit of 60 kilometers per hour (around 37 miles per hour).
About 3.3 kilometers (around 2 miles) of the tunnel were constructed using the shield tunneling method, deploying a 17.5-meter diameter (around 57 feet) tunnel-boring machine (TBM), according to Xinhua.