Can Short Earthquakes Imitate the long Ones? Seismic Analysis of a Fault-Crossing Tunnel via ABAQUS Explicit with Focus on Displacements at Critical Points

Ahmad Iqbal, & Yu Zhang

Submitted September 7, 2025, SCEC Contribution #14302, 2025 SCEC Annual Meeting Poster #TBD

This study examines how fault-crossing tunnels respond to earthquakes of varying durations, focusing on whether short duration seismic windows can effectively simulate the effects of longer duration earthquakes. Specifically, this study compares the three earthquake durations of the same seismic event to determine whether shorter seismic events can produce similar results to longer ones, helping to reduce both computational time and costs without compromising the accuracy of displacement predictions. For this purpose, three identical tunnel models were created in ABAQUS Explicit to simulate different seismic conditions: (1) a 2 second peak acceleration window, (2) a 10 second strong motion window, and (3) the full 90 second earthquake acceleration data of Chi-Chi 1999 earthquake. The results suggest that the 10 second strong motion window, when appropriately selected from a full-length earthquake, closely matches the displacement behavior of the 90 second earthquake, with only minimal differences. This finding indicates that, with careful selection, shorter earthquake durations can serve as reliable approximations for longer seismic events, making them valuable for time efficient seismic analysis. However, for precise structural design and long-term stability assessments, where sustained seismic loading is critical, the full seismic event duration is still recommended. This study demonstrates how computational resources can be saved without sacrificing accuracy in preliminary seismic evaluations in the form of displacements, particularly for fault crossing tunnel models. Future researches may explore dynamic scaling methods and more complex fault geometries to further enhance this study’s applicability.

Key Words
Fault Crossing Tunnel, Seismic Simulation, ABAQUS Explicit, Earthquake Duration

Citation
Iqbal, A., & Zhang, Y. (2025, 09). Can Short Earthquakes Imitate the long Ones? Seismic Analysis of a Fault-Crossing Tunnel via ABAQUS Explicit with Focus on Displacements at Critical Points. Poster Presentation at 2025 SCEC Annual Meeting.

Related Projects & Working Groups
Earthquake Geology