Behaviour of tunnels with different geometries under dynamic loading conditions

With the rapidly increasing population around the world, issues such as transportation and the use of underground spaces in urban areas have become increasingly significant. Tunnels are being used more and more for the benefit of humanity in both of these areas. Given the high costs associated with tunnel construction and maintenance, these structures are expected to offer substantial safety during earthquakes and require minimal upkeep once operational. Although it is known that underground structures have much higher earthquake performance than above-ground structures, tunnel damages caused by earthquakes, especially in the last century, have caused us to question our knowledge of tunneling and these situations have been reported in detail. In this thesis, the cumulative studies conducted by taking into account the damages reported on this subject were reviewed. In addition to that, tunnel behavior varies with environmental conditions, shape, and depth are assessed using finite element analysis. In general, it is proven that tunnels perform better with increasing depth and circularization of their shape.