Research overview
Using the Second Jiaozhou Bay Subsea Tunnel in Qingdao, which crosses the Cangkou fault, this study combines deterministic ground-motion simulation with the modified domain reduction method (MDRM) to investigate how the tunnel–fault intersection angle affects seismic deformation modes.
For a prescribed source and regional-site model, the six discrete alignments show different, non-monotonic patterns of normal and shear strain. The 42° case has relatively high normal strain and the lowest shear strain; the 57° case has the highest equivalent strain. Changes in alignment and the associated spatial sampling of ground motion primarily alter the combination of normal and shear strains, rather than producing a monotonic increase in overall strain with angle.