Current state of design and construction for the St. Kanzian tunnel chain / Aktueller Planungs‐ und Ausführungsstand der Tunnelkette St. Kanzian

Abstract

The St. Kanzian tunnel chain lies near the Völkermarkt reservoir and is part of the Mittlern-Althofen approval section of the Koralmbahn line in Carinthia. Of the six tunnels in the St. Kanzian tunnel chain, the 495 m long Kühnsdorf green tunnel (cut-andcover) has already been completed. The construction of the 230 m long Peratschitzen green tunnel (a cut-and-cover noise protection tunnel) and the 620 m long Srejach Tunnel (top-down construction) started in summer 2015. Work should start on the Untersammelsdorf, Stein and Lind Tunnels (all mined tunnels), in spring/summer 2016. The tunnels lie partially in challenging geological conditions (lacustrine sediments), all with shallow overburden, and require special measures for support and ground improvement (bored piles, jet grouting). Particular attention has been paid to later maintenance costs, which have to be considered in the course of the design work.