investigation of the impact of soil models and computational model width on the behavior of underground structures under earthquake effects: a case study of the underground section of urban railway line no. 3, Nhon - Hanoi station

Abstract

The analysis of underground structures subjected to seismic loading is a critical concern, particularly in densely populated urban areas like Hanoi. This research explores the influence of model width in Plaxis simulations, demonstrating that increasing the calculation model's width results in stabilized displacement at the crown of the left tunnel when the boundary distance is nine times the tunnel diameter. This ensures computational efficiency and convergence of results. Furthermore, the study assesses geotechnical models, with the HS Small model outperforming the HS model due to its superior capability to simulate soil behavior under small-strain conditions, reducing inaccuracies and delivering enhanced precision. The research, conducted on Hanoi Metro Line 3 (Nhổn – Hanoi Station), aims to identify and implement the most effective numerical modeling approach to ensure safe and sustainable underground construction in seismically active regions.