The world's largest-diameter underwater shield tunnel has been completed in China.
According to Interesting Engineering, the capital of Shandong Province in East China, Jinan, has made a world record for the largest tunnel using the largest available tunnel boring machine (TBM) on Earth.
The Shanhe shield machine digs the tunnel at an advanced rate of 52.5 to 59 ft (16 to 18 m), which is also a new world record for 17-meter-class shield construction.
The construction of the tunnel started on September 1, 2024. The underwater part of the tunnel is completed in a record-breaking 110 days, while the rest of the work is in process.
The workers have constructed a two-mile section beneath the Yellow River, featuring a 55.8-foot diameter and 500 pipe rings.
The tunnel project led by China Railway 14th Bureau Group aims to improve travel between the south and north sides of the Yellow River. The two-way tunnel will have three lanes in each direction designed for speeds up to 37.2 mph.
The Jinan Huanggang Road Yellow River Crossing Tunnel is scheduled to be completed in late 2025, which will be a new record.
