Numerical Modeling of Tunnel Excavation and Support Using the Deconfinement Method for Static and Seismic Conditions

<p>In this paper, an analysis of the phase construction of a tunnel with support in static and seismic conditions is made. The PLAXIS 2D software package was used for the problem's numerical modelling. A parametric analysis of the excavation using the deconfinement method (1-ß) was made on an actual tunnel with support in the excavation phase and primary lining with sprayed concrete and anchors. From the conducted analysis, it can be concluded that through the so-called method 1-β, i.e., the percentage enabled realisation of the deformations in the excavation, can successfully model the time needed to set up the support and obtain relevant parameters for dimensioning the elements of the lining for different load cases in static and seismic conditions and stages of performance.</p>