ENR reports that a Tunnel Boring Machine or TBM is stuck for the second time in two weeks on Pittsburgh’s light rail expansion project dubbed the North Shore Connector Project. As we described in a previous post, the project will consist primarily of a tunnel underneath the Allegheny River. The drilling began the week of March 3 and has been progressing at a rate of 30-ft/day or 5-ft/day faster than the original goals. Read on for a location map of the project, or download the Google Earth KMZ file showing the project area. (File photo of TBM)
In the mountains of Peru a tunnel-boring machine named â€œPacha Mamaâ€ is grinding through the heart of the Andes under rock as deep as 6,890 ft. It is carving away at a 20.2-kilometer-long tunnel through the South American Continental Divide to deliver water to arid coastal farmland.
This is a really interesting project, known as the Los Olmos project, and a nice little article. Normally for a civil tunnel project you drill geotechnical holes beforehand to know what kind of material you’re dealing with. In this case, because of the depth, they don’t have that luxury, so all decisions will be made on the fly. The depth of the tunnel creates some very challenging rock mechanics and logistics problems as well! (Illustration by Odebrecht)