Research


The following is a concise overview of the research that the group is involved with. It is organized by topics, but of course there is a necessary overlap among topics. Credit must be given to the students, visitors, and faculty collaborators who have worked with us and have pushed the field forward.

Fracture Mechanics
Discontinuous Media
Autoadaptive Systems
Analytical and Numerical Models
Soil-Structure Interaction
Tunnels
Problem Soils
Extreme Events
Current Projects

Soil-Structure Interaction

The work is conducted at the interface between geotechnical and structural engineering. The interest is on the load-transfer mechanisms between a structure and the surrounding ground, and compatibility of deformations between the ground and the structure.

Projects include the investigation of the failure of the Daikai station in Kobe, damage to concrete piles during earthquakes, and tunneling.

The Daikai station, a cut and cover structure in the subway system in Kobe, collapsed during the Hyogoken-Nambu earthquake of January 17, 1995 in Japan. This is the first well documented underground structure not crossing an active fault that has completely collapsed during an earthquake without liquefaction of the surrounding soil.
View of the Daikai station after reconstruction
Dynamic numerical analyses show that, for a given earthquake, there are two key factors that determine the response of an underground structure: the relative stiffness between the structure and the degraded surrounding ground, and the frictional characteristics of the interface. Similar observations apply to piles. Pile failure due to ground shaking takes place first near the pile head, where bending moments and shear forces are the largest. Other locations where large cracks may occur are near an interface between layers with large differences in stiffness; at the location of the second largest moment; and at cut-off locations of the longitudinal reinforcement.
  • Loukidis, D., Salgado, R., and Bobet, A. (2001). Seismic design of Pile Foundations in Southern Indiana. Proceedings: Fourth International Conference on recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics Symposium in Honor of Professor W.D. Liam Finn. Paper No. 8.09, pp. 1-6.

  • Huo, H., Bobet, A., Fernandez, G., and Ramirez, J. (2003). Seismic Evaluation of the failure of the Daikai Station During the Kobe Earthquake. Proceedings of the 11th International Conference on Soil Dynamics & Earthquake Engineering and 3rd International Conference on Earthquake Geotechnical Engineering, Vol. II, pp. 758-765.

  • Lee, H.S., and Bobet, A. (2005). Laboratory Evaluation of Pullout Capacity of Reinforced Silty Sands in Drained and Undrained Conditions. ASTM Geotechnical Testing Journal, Vol. 28, No. 4, pp. 370-379.

  • Huo, H., Bobet, A., Fernandez, G., and Ramirez, J. (2005). Load Transfer Mechanisms between Underground Structure and Surrounding Ground: Evaluation of the Failure of the Daikai Station. ASCE Journal of Geotechnical and Geoenvironmental Engineering, Vol. 131, No. 12, pp. 1522-1533.

  • Parra-Montesinos, G.J., Bobet, A., and Ramirez, J. (2006). Evaluation of Soil-Structure Interaction And Structural Collapse In Daikai Subway Station During Kobe Earthquake. American Concrete Institute, Structural Journal, Vol. 103, No. 1, pp. 113-122.

  • Huo, H., Bobet, A., Fernandez, G., and Ramirez, J. (2006). Analytical Solution for Deep Rectangular Structures Subjected to Far-Field Shear Stresses. Tunnelling and Underground Space Technology, Vol. 21, No. 6, pp. 613-625.

  • Bobet, A., Fernandez, G., Ramirez, J., and Huo, H. (2006). A practical method for assessment of seismic-induced deformations of underground structures. GeoCongress 06. CD ROM Proceedings, 6 pp.

  • Smith-Pardo, J. and Bobet, A. (2007). Behavior of Rigid Footings under Combined Axial Load and Moment. ASCE Journal of Geotechnical and Geoenvironmental Engineering, Vol. 133, No. 10, pp. 1203-1215.

  • Bobet, A., Fernandez, G., Huo, H., and Ramirez, J. (2008). A Practical Procedure to Estimate Seismic-Induced Deformations of Shallow Rectangular Strutures. Canadian Geotechnical Journal, Vol. 45, No. 7, pp. 923-938.

  • Jung, C.M. and Bobet, A. (2008). Seismic Earth Pressures Behind Retaining Walls: Effects of Rigid-body Motions. ASCE Geotechnical Earthquake Engineering and Soil Dynamics Conference, GSP-181, CD-ROM Proceedings, 11 pp.

  • Jung, C.M., Bobet, A., and Fernandez, G. (2010). Analytical solution for the response of a flexible retaining structure with an elastic backfill. International Journal for Analytical and Numerical Methods in Geomechanis. Vol. 34, pp. 1387-1408.

  • Bobet, A. (2009). La Falla de la Estacion de Daikai. IV Congreso Iberoamericano de Ingeniería Civil.Foundation of Civil Engineers of Venezuela (FUNDAVIC), Merida, Venezuela. Paper A.1.

  • Bobet, A. (2011). Considerations for Seismic design of Cut and Cover Structures. Geotecnia, Sociedad Mexicana de Ingenieria Geotecnica, A.C., June-August 2011 Issue, pp. 18-25.

  • Bobet, A. (2012). Comportamiento Sismico de Tuneles. Revista Internacional de Desastres Naturales, Accidentes e Infraestructura Civil, Vol. 12, No. 1, pp. 69-75.

  • Guo, J., Chen, J. and Bobet, A. (2013). Influence of a Subway Station on the Inter-story Drift Ratio of Adjacent Surface Structures. Tunnelling and Underground Space Technology, Vol. 35, pp. 8-19.

  • Sandoval, E. and Bobet, A. (2015). Undrained seismic response of underground structures. 6th International Conference on Earthquake Geotechnical Engineering, 1-4 November 2015. Christchurch, New Zealand.

  • Bobet, A. (2016). Respuesta Sismica de Tuneles. 18 Convencion Cientifica de Ingenieria y Arquitectura, La Habana, Cuba, 21-25 November, 2016, paper No. 3CIIC37, 11 pp.

  • Yan, X., Yuan, J., Yuan, Y., Bobet, A., and Yu, H. (2016). Multi-point Shaking Table Test Design for Long Tunnels under Non-uniform Seismic Loading. Tunnelling and Underground Space Technology, Vol. 59, pp. 114-126.

  • Yu, H., Chen, J., Bobet, A., and Yuan, Y. (2016). Damage observation and assessment of the Longxi tunnel during the Wenchuan earthquake. Tunnelling and Underground Space Technology, Vol. 54, pp. 102-116.

  • Sandoval, E. and Bobet, A. (2017). Effect of frequency and flexibility ratio on the seismic response of deep tunnels. Underground Space, Vol. 2, No. 2, pp. 125-133.

  • Yu, H., Yuan, Y. and Bobet, A. (2017). Seismic Analysis of Long Tunnels: A review of simplified and unified methods. Underground Space, Vol. 2, No. 2, pp. 73-87.

  • Bobet, A. and Yu, H. (2017). Seismic Distortions of a Deep Circular Tunnel in Elastic Slightly Anisotropic Ground. Underground Space, Vol. 2, No.2, pp134-147.

  • Yu, H., Zhang, Z., Chen, J., Bobet, A., Zhao, M. and Yuan, Y. (2018). Analytical solution for longitudinal seismic response of tunnel liners with sharp stiffness transition. Tunnelling and Underground Space Technology, Vol. 77, pp. 103-114.

  • Yu, H., Yan. X., Bobet, A., Yuan, Y., Xu, G., and Su, Q. (2018). Multi-point shaking table test of a long tunnel subjected to non-uniform seismic loadings. Bulletin of Earthquake Engineering, Vol. 16, No. 2, pp. 1041-1059.

  • Sandoval, E. and Bobet, A. (2019). Drained and Undrained Seismic Response of Underground Structures. WTC2019, 2019 World Tunnel Congress, Naples, Italy, May 3-9, accepted.

  • Chen, J., Yuan, Y., Bobet, A. and Yu, H. (2019). Shaking table tests of transition tunnel connecting TBM and drill-and-blast tunnels. Tunnelling and Underground Space Technology, Vol. 96, Article 103197 , https://doi.org/10.1016/j.tust.2019.103197

  • Sandoval, E. and Bobet, A. (2019). Respuesta Sismica de Estructuras Subterraneas / Seismic Response of Underground Structures. IX Congreso Nacional de Ingenieria Sismica, Santiago de Cali, Colombia, May 29-31, accepted.

  • Sandoval, E.A. and Bobet, A. (2019). Comportamiento sismico de tuneles bajo carga drenada y no drenada. Primer Congreso Internacional de Ingenieria Vial, Universidad del Cauca, Popayan, Colombia, October 2-4, 2019. Accepted.

  • Sandoval, E.A. and Bobet, A. (2019). Undrained Seismic Response of Tunnels. IS-Cambridge 2020: 10th International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground: 29 and 30 June 2020. Cambridge, UK. Accepted.

  • Sandoval, E and Bobet, A. (2020). Seismic response of underground structures under undrained loading with excess pore pressures accumulation. Tunnelling and Underground Space Technology, https://doi.org/10.1016/j.tust.2019.103255.

  • Tsinidis, G., de Silva, F., Anastasopoulos, I., Bilotta, E., Bobet, A., Hashash, Y., He, Ch., Kampas, G., Knappett, J., Madabhushi, G., Nikitas, N., Pitilakis, K., Silvestri, F., Viggiani, G. and Fuentes, R. (2020). Seismic behaviour of tunnels: from experiments to analysis. Tunnelling and Underground Space Technology, Vol. 99, https://doi.org/10.1016/j.tust.2020.103334.

  • Sandoval, E. and Bobet, A. (2020). The undrained seismic response of the Daikai Station. Tunnelling and Underground Space Technology, Vol. 103, https://doi.org/10.1016/j.tust.2020.103474.

  • Sandoval, E. and Bobet, A. (2020). Effect of input frequency on the seismic response of deep circular tunnels. Soil Dynamics and Earthquake Engineering, Vol. 139, https://doi.org/10.1016/j.soildyn.2020.106421.

  • Savigamin, Ch. and Bobet, A. (2021). Seismic response of a deep circular tunnel subjected to axial shear and axial bending. Tunnelling and Underground Space Technology, Vol 112, https://doi.org/10.1016/j.tust.2021.103863.

  • Chen, G., Yu, H. and Bobet, A. (2022). Analytical solution for seismic response of deep tunnels with arbitrary cross-section shape in saturated orthotropic rock. Rock Mechanics and Rock Engineering, accepted.

  • Vitali, O., Celestino, T. and Bobet, A. (2020). Analytical solution for a deep circular tunnel in anisotropic ground and anisotropic geostatic stresses. Rock Mechanics and Rock Engineering, Vol. 53, pp. 3859-3884. https://doi.org/10.1007/s00603-020-02157-5.

  • Vitali, O., Celestino, T. and Bobet, A. (2021). New modeling approach for tunnels under complex ground and loading conditions. Soils and Rocks, Vol 44, No. 1, pp. 1-8, doi: https://doi.org/10.28927/SR.2021.052120.

  • Savigamin, Ch. and Bobet, A. (2021). Seismic response of a deep circular tunnel subjected to axial shear and axial bending. Tunnelling and Underground Space Technology, Vol. 112, https://doi.org/10.1016/j.tust.2021.103863.

  • Vitali, O., Celestino, T. and Bobet, A. (2021). 3D face effects of tunnels misaligned with the principal directions of material and stress anisotropy. Tunnelling and Underground Space Technology, Vol. 122, https://authors.elsevier.com/c/1eMjA39eM4EPf5.

  • Vitali, O., Celestino, T. and Bobet, A. (2021). Construction strategies for a NATM tunnel in Sao Paulo, Brazil, in residual soil. Underground Space, Vol. 7, No. 1, pp. 1-18. https://doi.org/10.1016/j.undsp.2021.04.002.

  • Vitali, O., Celestino, T. and Bobet, A. (2021). Behavior of tunnels excavated with dip and against the dip. Underground Space, Vol. 6, No. 6, pp. 709-717. https://doi.org/10.1016/j.undsp.2021.04.001.

  • Chen, G., Yu, H. and Bobet, A. (2022). Analytical solution for seismic response of deep tunnels with arbitrary cross-section shape in saturated orthotropic rock. Rock Mechanics and Rock Engineering, Vol. 55, pp. 5863-5878. https://doi.org/10.1007/s00603-022-02935-3.

  • Bobet, A. (2023). Static and Seismic Response of Deep Spherical Cavities. Rock Mechanics and Rock Engineering, Vol. 56, pp. 9135-9148, https://doi.org/10.1007/s00603-023-03540-8.

  • Chen, G., Yu, H. and Bobet, A. (2023). Analytical solution for seismic response of deep tunnels with arbitrary cross-section and voids behind the liner. Rock Mechanics and Rock Engineering, https://doi.org/10.1007/s00603-023-03323-1.

  • Bobet, A., Yu, H. and Tiwari, N. (2023). Seismic Response of Shallow Circular Openings to Rayleigh Waves. Tunnelling and Underground Space Technology, Vol. 135, https://doi.org/10.1016/j.tust.2023.105036.

  • Chen, G., Yu, H. and Bobet, A. (2023). Analytical solution for seismic response of deep tunnels near a fault zone subjected to SH waves. Rock Mechanics and Rock Engineering, https://doi.org/10.1007/s00603-023-03530-w.

  • Savigamin, Ch. and Bobet, A. (2023). Seismic response of deep circular tunnels subjected to P-waves. Soil Dynamics and Earthquake Engineering, https://doi.org/10.1016/j.soildyn.2023.108338.

  • Savigamin, Ch. and Bobet, A. (2024). Seismic response of deep circular tunnels subjected to S-waves: Axial bending. Underground Space, Vol. 17, pp. 267-279, https://doi.org/10.1016/j.undsp.2023.11.013.

  • Vitali, F.P.M., Vitali, O.P.M., Bobet, A. and Celestino, T.B. (2024). Technical Note: Modeling Optimization for Highly Nonlinear Shallow Tunnel Analyses. Soils and Rocks, Vol. 47, No. 1, 7 pp. https://doi.org/10.28927/SR.2024.000923.

  • Vitali, F.P.M., Vitali, O.P.M., Celestino, T.B. and Bobet, A. (2024). Numerical Analysis of Relative Density Effects on Shallow TBM Tunnel Excavation: Ground Behavior and Principal Strains at Surface in Greenfield Conditions. Tunnelling and Underground Space Technology, Vol. 154, https://doi.org/10.1016/j.tust.2024.106104.

  • Sandoval, E. and Bobet, A. (2024). Effect of Input Frequency on the Seismic Response of Deep Tunnels. 18th World Conference on Earthquake Engineering, WCEE2024, Milan, Italy.

  • Sandoval, E. and Bobet, A. (2024). Seismic Response of Tunnels with Saturated Nonlinear Ground. 18th World Conference on Earthquake Engineering, WCEE2024, Milan, Italy.

  • Tiwari, N., Ahmad, Md.A. and Bobet, A. (2024). Seismic Response of Unsupported Shallow Circular Openings to Rayleigh Waves. 18th World Conference on Earthquake Engineering, WCEE2024, Milan, Italy.

  • Ahmad, Md Asad and Bobet, A. (2024). Effect of Flexibility Ratio on Shallow Circular Tunnels Subjected to Love Waves. ASCE Geo-congress 2025 – Geotechnical Frontiers. Accepted.

  • Ahmad, Md Asad and Bobet, A. (2024). Mechanically Stabilized Earth Walls with Intersecting Horizontal Obstruction, Transportation Research Board. Paper TRBAM-25-00907. Accepted.

  • Ahmad, Md Asad and Bobet, A. (2024). Mechanically Stabilized Earth Walls with a Horizontal Obstruction. ASCE Geo-congress 2025 – Geotechnical Frontiers. Accepted.

  • Vitali, F.P.M., Vitali, O.P.M., Celestino, T. and Bobet, A. (2025). Influence of Boundary Conditions on Centrifuge Tunnel Tests. ASCE Geo-Congress 2026. Submitted.

  • Sandoval, E. and Bobet, A. (2025). Seismic response of deep rectangular tunnels considering nonlinear ground and excess pore pressures accumulation. Tunnelling and Underground Space Technology, Vol. 164, https://doi.org/10.1016/j.tust.2025.106757.

  • Ahmad, Md Asad and Bobet, A. (2024). Mechanically Stabilized Earth Walls with Intersecting Horizontal Obstruction, Transportation Research Board. Paper TRBAM-25-00907. Accepted.

  • Ahmad, Md Asad and Bobet, A. (2024). Mechanically Stabilized Earth Walls with a Horizontal Obstruction. ASCE Geo-congress 2025 – Geotechnical Frontiers. Accepted.