A Numerical Study on the Behavior of NATM Tunnels under Seismic Loading

Abstract

The necessity of tunnels is becoming more and more essential in the modern world because of their various purposes and independence of the surface life despite their shape. This paper aims at examining the behavior of a seismically loaded NATM tunnel buried in well graded gravel. The maximum displacement due to overburden pressure was obtained which was 30.38 mm as well as the vertical and lateral displacements of a maximum 53 mm and 17 mm, respectively. The peak ground acceleration (PGA) is found to be normal when comparing it with the PGA map of Iraq. Lastly, the Fourier amplitude spectrum was represented in order to show its relationship with the ground input energy.