Nonlinear Seismic Response of Tunnels in Longitudinally Inhomogeneous Strata Subjected to Obliquely Incident SV Waves

Xiaole Jiang¹, Jingqi Huang^2,*, Xu Zhao^1,*, Wenlong Ouyang³, Xianghui Zhao⁴
1 Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education, Beijing University of Technology, Beijing, China
2 Beijing Key Laboratory of Urban Underground Space Engineering, School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing, China
3 China Resources Land (Wuhan) Co., Ltd., Wuhan, China
4 Xinjiang Academy of Transportation Sciences Co., Ltd., Urumgi, China
* Corresponding Author: Jingqi Huang. Email: email ; Xu Zhao. Email: email
(This article belongs to the Special Issue: Multiscale, Multifield, and Continuum-Discontinuum Analysis in Geomechanics )

Computer Modeling in Engineering & Sciences https://doi.org/10.32604/cmes.2026.078230

Received 26 December 2025; Accepted 16 February 2026; Published online 04 March 2026

Download PDF

Abstract

To address the complex seismic response of long tunnels longitudinally crossing heterogeneous geological formations, this study proposes a three-dimensional SV-wave oblique-incidence input method that accounts for the initial disturbance of the wave field induced by geological heterogeneity. The method transforms equivalent two-dimensional free-field responses into equivalent nodal forces applied at the boundaries of a 3D numerical model. A longitudinally heterogeneous “hard-soft-hard” site and tunnel system is established, in which the surrounding rock is modeled using the Mohr-Coulomb constitutive law, while the concrete lining is described by the concrete damaged plasticity model. The deformation patterns and failure mechanisms of the site-tunnel system under SV-wave excitation are systematically investigated. The results indicate that seismic damage under SV-wave loading is mainly concentrated in the soft-rock region. Failure of the soft surrounding rock induces pronounced sliding of the overlying hard rock, and the tunnel suffers severe damage due to the combined effects of soft-rock failure and strong ground shaking. Parametric analyses further show that smaller impedance ratios, larger soft-rock widths, and larger incidence angles significantly intensify the seismic response of the tunnel. The findings of this study provide valuable insights for the seismic design of tunnels crossing longitudinally heterogeneous geological formations.