Here's how the tunnel boring machine, or TBM, works: As the 200-ton TBM moves forward, a round cutter head studded with titanium teeth grinds into the tunnel face and splits large chunks off the rock.

VIRGINIA BEACH, Va. — After multiple delays, including a 9-month delay involving a century-old anchor, the Chesapeake Bay Bridge-Tunnel (CBBT) expansion achieved a major milestone as its tunnel boring ...

China has completed the production of its largest tunnel-boring machine ... The machine is 476 feet long and weighs about ...

China's largest shield tunneling machine cutter head, with a record-breaking diameter of 16.64 meters, descended at the construction site of the Haitai Yangtze River Tunnel in East China's Jiangsu ...