Dynamic response of a double-deck circular tunnel embedded in a full-space

• Published in: Tunnelling and underground space technology Vol. 59; pp. 146 - 156
• Main Authors: Clot, Arnau, Arcos, Robert, Romeu, Jordi, Pàmies, Teresa
• Format: Journal Article Publication
• Language: English
• Published: Elsevier Ltd 01.10.2016
• Subjects: Coupling subsystems; Double-deck tunnel; Enginyeria mecànica; Mecànica dels sòls; Soil mechanics; Tunnels; Túnels; Underground vibrations; Viscoelastic full-space; Àrees temàtiques de la UPC; Underground vibrations; Double-deck tunnel; Coupling subsystems; Viscoelastic full-space
• ISSN: 0886-7798; 1878-4364
• DOI: 10.1016/j.tust.2016.07.004

•A model for obtaining the dynamic response of a double-deck circular tunnel is developed.•The response of the tunnel is compared to the one of a simple tunnel, finding significant differences between them.•The dynamic behavior of the interior floor clearly affects the floor-tunnel coupling forces. A three-dimensional dynamic model for calculating the ground-borne vibrations generated by harmonic loads applied on the interior floor of a double-deck circular tunnel is developed. The response of the system is obtained coupling the interior floor subsystem and the tunnel-soil subsystem in the wavenumber-frequency domain. The interior floor is modeled as a thin plate of infinite length in the train circulation direction and the tunnel-soil system is described using the Pipe in Pipe model. Some numerical instabilities of the resulting expressions are overcome by using analytic approximations. The results show that the dynamic behavior of the interior floor clearly influences the magnitude of the coupling loads acting on the tunnel structure. The soil response to a harmonic load acting on the double-deck tunnel is compared to the one obtained for the case of a simple tunnel finding significant differences between them for the whole range of frequencies studied. The proposed model extends the prediction of train-induced vibrations using computationally efficient models to this type of tunnel structure.