Tunnel boring machine (TBM) tunnels are increasingly used in the construction of transport infrastructure, allowing for reduction of the environmental impact and cost and time of construction. Despite these advantages, TBM tunnels still face major challenges such as further cost reduction, the structural safety under earthquakes, and the improvement of safety during operation in the case of traffic tunnels (rail and road tunnels). To overcome these challenges, three innovative and very cost-effective concepts for the construction of TBM tunnels were recently developed by the author: the tunnel of improved seismic behavior (TISB) concept for improving structural safety of tunnels on soft ground in seismic areas and the tunnel multi-floor (TMF) and tunnel multi-gallery (TMG) concepts for road and rail tunnels, respectively, which allow an even greater cost reduction and improvement of safety in operation. In this paper these concepts are presented as well as their application in some specific cases, emphasizing the obtained added value.
Part of the book: Tunnel Engineering