Browsing by Subject "case history"

Now showing 1 - 1 of 1

Access status: Open Access ,
Tunneling through highly squeezing ground - a case history
(Wydawnictwa AGH, 2005) Pöttler, Rudolf; Starjakob, Franz; Spöndlin, Daniel
The adaptability of the New Austrian Tunneling Method in design and construction has been proven once more at the Strenger Tunnel, where highly squeezing rock mass caused considerably high deformations and loadings of the primary and secondary lining. By adjusting the support measures especially rock bolting and yielding steel elements installed in slots of the shotcrete lining large deformations up to 0.5 m due to progressive fracturing could be successfully mastered. Calculations using FE-models have been found to be helpful for decision making on site and therefore should increasingly by used in future. Calculations also showed that asymmetric rock mass behavior is not necessarily decisive for the loading of the inner concrete lining in case of extensive fracture processes. Thereby the general practice used in Austria to employ an unreinforced concrete lining was verified. For this decision it was considered that the shotcrete lining which undergoes repair works at the most critical sections will not completely fail but keep apart of its load bearing capacity with respect to normal forces.