| dc.description.abstract | In the fields of geology and geotechnical engineering, the study of faults and tunnels is
important. Particularly in seismically active regions, the presence of fault zones and fractured
geological formations introduces significant uncertainties in tunnel design and construction,
potentially posing serious threats to tunnel stability and safety. The inherent difficulty in
directly observing in situ soil layers and faults, compounded by the limited availability of data,
complicates the analytical process. To simulate various failure mechanisms, civil engineers
often simplify these complex problems and construct numerical or physical models. However,
the preparation of full-scale physical models is time-consuming and economically inefficient,
while numerical simulations require extensive preliminary work based on field investigations
or simplified physical model experiments. Additionally, the experimental process for centrifuge
models is also time-intensive, and the availability of research facilities equipped with
centrifuges is relatively limited.
To address these challenges, this study utilizes 1g fault experiments to simulate the
interaction between faults and tunnels, aiming to understand the impact of faults on tunnel
stability. The results are compared with centrifuge modeling tests to explore the correlation
between the two, thereby assessing the reliability of 1g fault experiments. The research focuses
on observing the interaction between shear zones and tunnels during reverse fault movements,
documenting the extent of the shear zones, tunnel inclination, tunnel displacement, and surface
impact area. This study seeks to provide a more straightforward yet accurate method for
investigating the interaction between faults and tunnels, offering valuable insights for
geological hazard assessment and infrastructure design in practical engineering.
This research, based on centrifuge modeling tests and large-scale 1g fault experiments,
explores the behavior of tunnels at different burial depths in terms of displacement, inclination,
and surface impact area. The study finds that when the burial depth is twice the tunnel height,
the horizontal and vertical displacement results from large-scale 1g fault experiments
overestimate by approximately 20% and 24%, respectively, while the tunnel inclination and
surface impact area are underestimated by 27% and 38%, respectively. Due to the closer
approximation of fault slip rates to real-world conditions in large-scale 1g fault experiments,
the behavior of shear zone development is more representative of actual scenarios. In contrast,
the stress environment in centrifuge model tests is more analogous to real-world conditions,
making the tunnel′s stress behavior, displacement, and inclination more similar to those in
actual situations. Therefore, both testing methods have their respective strengths and
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weaknesses when evaluating the behavior of tunnels affected by faults. Furthermore, reducing
the burial depth of tunnels leads to increased displacement and inclination, as well as an
expanded shear zone and surface impact area, necessitating a more conservative approach to
the placement of shallow-buried tunnels. | en_US |