This architectural drawing is Excavation stages of tunnel in detailing. The aim of the excavation cycle is to break up the rock with explosives, giving the required cross-sectional shape while the tunnel advances proportionally to the length of the drilling in the tunnel face. In this way, with successive cycles, the infrastructure is built gradually until the tunnel has been completed. In this drawing different stages of excavation of tunnel are given. For more details and information download the drawing file.
