The construction of a 20-km tunnel that travels some 6,900-ft below ground has finally restarted after being broken down for several months after being damaged by a rock burst. The Los Olmos tunneling project will bring rain forest water to thirsty coastal Peruvian residents by means of a water supply tunnel under the Andes Mountains. I first posted about the project in 2008, but it was about 4-months ago that ENR reported that the TBM was seriously damaged by rock bursts and the parts were not available to fix it. The rock bursts continue, and now it appears that the project is over 2-years behind the original schedule, breaking through in Spring of 2012 with tunnel completion following 6-months behind. [Source: ENR: Engineering News Record. Image: Odebrecht]
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New Tunnel Project In Peru Through Andes
From ENR:
In the mountains of Peru a tunnel-boring machine named “Pacha Mama†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)