Tunneling


View from a drone inside a tunnel executed by Bertha

wsdot View from a drone inside the SR 99 tunnel, executed by Bertha. Bertha, also known as Big Bertha, is a 57-foot-diameter (17.4 m) tunnel boring machine built specifically for the Washington State Department of Transportation’s (WSDOT) Alaskan Way Viaduct replacement tunnel project in Seattle.[1] It was made by Hitachi […]


Pipe jacking with open shield

The election of this type of perforation is influenced in great way of the type of ground and surface area of influence. Is absolutely necessary not to have groundwater levels and the ground has to be cohesive. This boring technic is inadvisable in free ground without cohesion, hard ground or […]


How a Tunnel-Boring Machine Drills Underground

“Video courtesy of CDM/HMM Joint Venture – For engineering enthusiasts and anyone who’s interested in the mechanics of siphon construction, this animation shows exactly how the 110-ton, 300-foot-long tunnel boring machine will drill a distance of nearly two miles, 100 feet beneath the New York Harbor seabed…”.