ABSTRACT

The choice of a suitable lining concept is elementary in conventional tunnelling under squeezing ground conditions. The use of yielding elements to create a targeted flexibility of the shotcrete lining is state of the art. The defined flexibility results in an overall different kinematic load-bearing capacity of the shotcrete lining. The functional relationship between the time-dependent material behaviour of the shotcrete and the load-dependent deformation behaviour of the yielding elements is decisive for the optimization of the lining concept. The aim of the work is to analyse the relationships between the yielding elements and the system behaviour of the shotcrete lining. With a three-dimensional numerical model, the kinematic behaviour of the overall system is analysed, with a focus on the interaction between ground, shotcrete lining and yielding elements. The influence of different ground and system parameters on the load acting on the ductile shotcrete lining is investigated.