Bye-Bye to Bertha, the world’s largest tunneling machine

wsdot This time-lapse video captures the difficult and challenging work to disassemble the world’s largest-diameter tunneling machine. For four months, crews cut, hoisted and trucked away 8,000 tons of the machine’s equipment and steel, removing it from inside the tunnel it had built. Up next – finishing the double-deck highway inside and installing all the operating systems to open Seattle’s new SR 99 tunnel by early 2019.

Large Underground Excavated Caverns

Rocscience Inc. The stability of large excavated caverns for underground powerhouses, metro stations and other facilities require careful design as well as precisely sequenced excavation and support installation. The most significant steps in the design and construction process are discussed in this lecture, by Dr. Evert Hoek. See the video on YouTube

The world’s first Variable Density Tunnel Boring Machine

MRTMalaysia Two types of TBMs are being used to excavate the tunnel for the MRT Sungai Buloh-Kajang Line. In the portion of the alignment going through the Kenny Hill Formation, Earth Pressure Balance (EPB) TBMs will be used while the world’s first Variable Density TBMs, which was specially developed jointly by world renowned TBM manufacturer Herrenknecht AG of Germany and MMC Gamuda joint venture, will be used to excavate in the Kuala Lumpur Limestone Formation … Read more

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 Zosen Sakai Works in Osaka, Japan, and the machine’s assembly was completed in Seattle in June 2013. Tunnel boring began on July 30, 2013, with … Read more

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…”.

Meet Crossrail’s giant tunnelling machines

Crossrail Project “Crossrail will use eight tunnel boring machines (TBMs) to construct the new tunnels under London. These huge machines will work 24 hours a day beneath the streets of London, excavating large volumes of ground and erecting the concrete tunnel lining…”.

The longest tunnel in the world

Largest Dams “The Gotthard Base Tunnel (GBT) is a railway tunnel in the heart of the Swiss Alps expected to open in 2016. With a route length of 57 km (35.4 mi) and a total of 151.84 km (94.3 mi) of tunnels, shafts and passages, it is the world’s longest rail tunnel, surpassing the Seikan Tunnel in Japan…”.