Integrating analytical solutions and finite element modeling for seismic assessment of tunnel and functional...

Tunnels are critical components of transportation infrastructure, particularly in seismically active regions where their performance governs network functionality and resilience. This study presents a unified analytical-numerical framework to evaluate the seismic response, damage behavior, and post-earthquake functionality of tunnels across four regions: Al Sharqiyah (Oman), North Gyeongsang (South Korea), the Himalayan region and Sichuan (China). The methodology integrates analytical solutions with finite element simulations (MIDAS GTS NX software) to capture soil-structure interaction (SSI) effects under varying seismic conditions. Tunnel performance is assessed using deformation parameters, damage index, fragility curves, and functionality indicators such as capacity loss and serviceability reduction. Results show a transition from deformation-controlled behavior in low seismic regions to brittle and fault-driven responses in high seismic zones. Numerical models predict higher deformation demands compared to analytical solutions. The proposed framework enables performance-based tunnel design and supports resilient infrastructure development under diverse seismic environments.