The Alto Maipo project consists of a hydroelectric plant which includes five high mountain intakes, 70 kilometers of tunnels at an average depth of 800 meters, two cavern power plants - Alfalfal II and Las Lajas- with a combined capacity of 531 MW and 17 kilometers of high voltage lines.
The relevant civil works consider 70 kilometers of tunnels excavated in solid rock, at an average depth of 800 meters. Its size is defined by the flow rate to be transported and the minimum dimensions required for the operation of the excavation machinery. The tunnels will conduct the water under pressure and at low speed, losing very little energy until it reaches the machine caverns.
Due to the mountain range area rock bursting problems have been registered. The require fortification in order to protect both human lives and the machinery necessary for the development of a tunnel.
For safety reasons MINAX® 80/4 rock mesh have been implemented: In order to provide the necessary energy absorption capacity in case of rock bursting that could occur due to the geological conditions of the tunnels of the Alto Maipo project.
At the same time, in order to optimize the fortification operation and safeguard the integrity of the workers, the MESHA® device has been implemented. The nailing is carried out fully mechanized.