Ground motion amplification by twin circular tunnels for obliquely incident seismic waves: effects of saturated poroelastic soil parameters
File(s)
Accepted version
Author(s)
Zhu, Jun
Kontoe, Stavroula
Li, Xiaojun
Liang, Jianwen
Chen, Su
Type
Journal Article
Abstract
Underground structures can significantly affect the ground motion and further influence the seismic design of aboveground structures around them. Although this issue has been well recognised and studied, it is not thoroughly addressed as a large number of factors are involved. This paper focuses on ground motion amplification induced by twin circular tunnels embedded in saturated poroelastic soil. The saturated poroelastic soil is modelled as a two-phase medium to consider parameters characterising the fluid phase. Three-dimensional scattering features of the twin tunnels for obliquely incident seismic waves are numerically investigated by a 2.5D finite element and boundary element hybrid model. It is shown that the presence of the twin tunnels can lead to significant modifications of the free-field motion, in terms of its magnitude and distribution. The three-dimensional oblique incidence scenario presents a more general perspective on the ground motion amplification. Moreover, the effects of saturated poroelastic soil parameters on the ground motion amplification, including soil permeability, groundwater levels, and the degree of saturation, are parametrically investigated. The differences in ground motion amplification patterns between the saturated poroelastic and dry poroelastic soil scenarios are notable, highlighting the effects of parameters characterising the fluid phase.
Date Issued
2024-11-01
Date Acceptance
2024-08-29
Citation
Soil Dynamics and Earthquake Engineering, 2024, 186
ISSN
0267-7261
Publisher
Elsevier
Journal / Book Title
Soil Dynamics and Earthquake Engineering
Volume
186
Copyright Statement
Copyright © 2024 Published by Elsevier Ltd. This is the author’s accepted manuscript made available under a CC-BY licence in accordance with Imperial’s Research Publications Open Access policy (www.imperial.ac.uk/oa-policy)
License URL
Subjects
CAVITIES
Degree of saturation
DYNAMIC STRESS-CONCENTRATION
ELASTIC-WAVES
Engineering
Engineering, Geological
Geology
Geosciences, Multidisciplinary
Ground motion amplification
Groundwater level
LAYERED HALF-SPACE
LINED TUNNELS
Obliquely incident seismic waves
Physical Sciences
PLANE
POROUS-MEDIA
SCATTERING
Science & Technology
SITE RESPONSE
Soil permeability
Technology
Twin tunnels
UNDERGROUND TUNNEL
Publication Status
Published
Article Number
108953
Date Publish Online
2024-09-03