A tridimensional finite element approach to model a tunnel with shotcrete and precast concrete

Abstract

This paper describes a numerical simulation with 3D finite elements of a tunnel. The viscoplastic law of Perzyna represents the rockmass behavior. The concrete, shotcrete or precast, is modeled as a viscoelastic material through the Maxwell and Kelvin chain models. Finite element simulations are performed by incorporating subroutines for viscoelastic concrete models in the ANSYS code. The method to simulate tunnel excavations is by activating and deactivating elements in sequential steps. In the first part of the paper two validations are performed. The analytical solution and the deformation achieved on the stabilization in the ANSYS code are compared with an unlined tunnel. A lined tunnel, with an elastic and viscoplastic rockmass combined with an elastic lining, is compared with the results of the GEOMEC91 code. In the second part, it is compared the same tunnel with two different concrete lining for two chain models. Finally, it is modeled the Kielder experimental tunnel, which in situ measured data is available.

Coding the “New Implicit Method” in MatLab for preliminary tunnel design

“…BERNAUD [4] validated this numerical code with the experimental values of the Boom clay in Belgium, and for a 230-m deep tunnel the in-situ convergence was about 2.20% and the numerical solution returned a convergence of 2.04% presenting an average difference of 0.16% (between GEO-MEC91 and experimental measures) showing the accuracy of the CEOMEC91 used here as the validation tool of the New Implicit Method (see Figure 6). QUEVEDO [10] and FIORE et al [6] compared the solution of the GEOMEC91 with the numerical solution given by software ANSYS and showed an accuracy of GEOMEC91 used here. The model used by Fiore presented an accuracy…”

Coding the 'New Implicit Method' in Matlab for Preliminary Tunnel Design

“…BERNAUD [4] validated this numerical code with the experimental values of the Boom clay in Belgium, and for a 230-m deep tunnel the in-situ convergence was about 2.20% and the numerical solution returned a convergence of 2.04% presenting an average difference of 0.16% (between GEO-MEC91 and experimental measures) showing the accuracy of the CEOMEC91 used here as the validation tool of the New Implicit Method (see Figure 6). QUEVEDO [10] and FIORE et al [6] compared the solution of the GEOMEC91 with the numerical solution given by software ANSYS and showed an accuracy of GEOMEC91 used here. The model used by Fiore presented an accuracy…”

Influence of the cracking consideration in the displacements of a shallow tunnel lined in steel-reinforced concrete: numerical model

“…The numerical methods allow the use of nonlinear and distinct constitutive models for the soil and the lining, the modeling of complex geometries and the consideration of boundary and loading conditions like those found in the field. Additionally, numerical simulations can reproduce the excavation process and the lining installation by the activation and deactivation method, as done in the studies of Bernaud [9], Fiore et al [10] and Quevedo [4].…”