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.

CHANGSHA -- China's self-developed tunnel boring machine with the biggest diameter ... which is intended to establish a major trans-river road link under the country's longest river, connecting ...

A 1,600-tonne tunnel boring machine has made it halfway through its journey to build the 3.5 mile (5.6km) Bromford Tunnel between Water Orton and Washwood Heath. Working about 40m (131ft ...