Hybrid Method for Analysis of Segmented Shotcrete Tunnel Linings

Abstract

When driving tunnels according to the New Austrian Tunneling Method. (NATM), shotcrete is applied onto the newly excavated areas of the tunnel surface. Large deformations occurring when driving tunnels under squeezing rock conditions lead to the destruction of a conventional shotcrete lining. As a remedy, segmented shotcrete linings characterized by an increased compliance have successfully been installed. In this paper a hybrid method for the analysis of such segmented tunnel linings is presented. It combines in situ displacement measurements with a thermochemomechanical material law for shotcrete. The application of this method to the Semmering pilot tunnel provides new insights into the load-carrying behavior of segmented tunnel linings.