Experiences With The Use Of The Conventional Mined Excavation Method In The Santiago Metro – Chile

The Santiago Metro is the largest rapid transit system in South America with 140 km of routes currently in operation. Most of the metro network was developed using the conventional mined excavation method, which was applied for the construction of running tunnels and stations often under shallow overburden conditions and densely built-up urban areas. This paper presents a brief snapshot of the historical evolution of the conventional mined tunnelling methods used for the Santiago Metro underground works, outlining relevant lessons learned along the way and how these cumulative experiences have enabled a continuous improvement and optimisation of design concepts and construction methodologies used for subsequent projects.