In this paper different approaches aimed at investigating the dynamic behaviour of circular tunnels in the transverse direction are presented. The analysed cases refer to a shallow tunnel built in an ideal soft clayey deposit excited by four different acceleration time histories characterised by significantly different frequency content. The adopted approaches include: 1) one-dimensional (1D) numerical analyses performed modelling the soil as a single phase visco-elastic non-linear medium, the results of which are then used to evaluate the input data for selected analytical solutions proposed in the literature (uncoupled approach); 2) 2D fully coupled Finite Element simulations adopting visco-elastic and visco-elasto-plastic constitutive assumptions for the soil and the lining (coupled approach); 3) 2D quasi-static Finite Element simulations adopting the same constitutive hypotheses of the fully coupled dynamic analyses. The three approaches, when a proper calibration of the soil parameters is undertaken, provide comparable results in the case of the visco-elastic assumption for the soil. The different constitutive hypotheses adopted in the 2D Finite Element simulations prove to play a significant role on the seismic-induced loads and curvature of the lining.
Titolo: | Analysis of tunnel behaviour under seismic loads using different numerical approaches |
Autore/i: | A. Amorosi; BOLDINI, DANIELA; G. Elia |
Autore/i Unibo: | |
Anno: | 2011 |
Titolo del libro: | Proceedings of the 5th International Conference on Earthquake Geotechnical Engineering (5ICEGE) |
Pagina iniziale: | 1 |
Pagina finale: | 13 |
Abstract: | In this paper different approaches aimed at investigating the dynamic behaviour of circular tunnels in the transverse direction are presented. The analysed cases refer to a shallow tunnel built in an ideal soft clayey deposit excited by four different acceleration time histories characterised by significantly different frequency content. The adopted approaches include: 1) one-dimensional (1D) numerical analyses performed modelling the soil as a single phase visco-elastic non-linear medium, the results of which are then used to evaluate the input data for selected analytical solutions proposed in the literature (uncoupled approach); 2) 2D fully coupled Finite Element simulations adopting visco-elastic and visco-elasto-plastic constitutive assumptions for the soil and the lining (coupled approach); 3) 2D quasi-static Finite Element simulations adopting the same constitutive hypotheses of the fully coupled dynamic analyses. The three approaches, when a proper calibration of the soil parameters is undertaken, provide comparable results in the case of the visco-elastic assumption for the soil. The different constitutive hypotheses adopted in the 2D Finite Element simulations prove to play a significant role on the seismic-induced loads and curvature of the lining. |
Data prodotto definitivo in UGOV: | 13-giu-2013 |
Appare nelle tipologie: | 4.01 Contributo in Atti di convegno |