Interaction of Underground Tunnel and Existing Shallow Foundations Affected by Normal Faults

Document Type : Research Note

Authors

1 School of Civil Engineering, Iran University of Science and Technology

2 Department of Civil Engineering, Islamic Azad University, South Tehran Branch

Abstract

In major earthquakes, permanent ground deformations due to the fault movements
cause serious damage to the foundations and structures. Although many of
structural seismic design codes have recommended avoiding the construction of
structures in the adjacent to active faults, it is not always a viable option. For
example, the lifeline facilities such as gas tunnels, water supply tunnels and
transportation tunnels, due to their extensive length, cannot often avoid crossing
active faults. Therefore, it is necessary to evaluate the interaction mechanism
between structures and fault rupture for effective design to reduce the hazards
associated with surface faulting. This study investigates the interactions of
underground tunnel and existing shallow foundation affected by normal fault
using the finite element method. The results show that the existence of a tunnel
changes the fault rupture path and in some cases can increase the foundation
rotation. It causes the occurrence of severe level of damage to the structure and
increases fear about its instability.

Keywords


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