Seismic vulnerability of shallow tunnels subjected to far-field long-period ground motions
5
Issued Date
2024-01-01
Resource Type
ISSN
02677261
Scopus ID
2-s2.0-85175257612
Journal Title
Soil Dynamics and Earthquake Engineering
Volume
176
Rights Holder(s)
SCOPUS
Bibliographic Citation
Soil Dynamics and Earthquake Engineering Vol.176 (2024)
Suggested Citation
Cabangon L.T., Elia G., Rouainia M., Keawsawasvong S., Ornthammarath T. Seismic vulnerability of shallow tunnels subjected to far-field long-period ground motions. Soil Dynamics and Earthquake Engineering Vol.176 (2024). doi:10.1016/j.soildyn.2023.108313 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/90961
Title
Seismic vulnerability of shallow tunnels subjected to far-field long-period ground motions
Author's Affiliation
Other Contributor(s)
Abstract
Extensive documentation and research have highlighted the destructive impact of near-field earthquakes on underground structures, while the effects of far-field earthquakes remain relatively less explored. In regions such as Bangkok and Singapore, where active seismic faults are located at a significant distance, the influence of far-field motions on tunnels tends to be ignored. However, far-field earthquakes are generally less destructive than near-field motions due to their low peak ground acceleration, peak ground velocity, and Arias intensity, resulting in lower energy. Conversely, far-field earthquakes tend to have a longer duration than near-field and a higher probability of containing long-period waves, which can lead to higher responses in the low-frequency region of the response spectrum. When these far-field ground motions are applied to thick layers of soft natural clays, a common geological feature in Bangkok, they can undergo significant amplification in the long-period range, resulting in large soil displacements and shear strains. Consequently, this induces significant forces in the tunnel lining comparable to those generated by near-field earthquakes. This paper presents a comprehensive study of this rarely investigated topic, using advanced numerical simulations to analyse the seismic behaviour of a shallow circular tunnel in Bangkok soft clays subjected to long-period earthquakes. The results show that far-field earthquakes have the potential to generate forces in the tunnel lining that are equally destructive as those induced by near-field motions. Therefore, these far-field effects should be accounted for in the seismic design of tunnels.