The effect of two-dimensional and three-dimensional modeling on the seismic response of tunnels in the jointed rock mass by pseudo-static analysis

Note that the relative stability of these structures against seismic loads is not a reason for this insignificance. Today, most seismic analyses are performed with the help of two-dimensional numerical methods due to their convenience. However, in some projects, three-dimensional tunnel analysis, especially in jointed rocks, to select a more accurate support system can be a crucial step in successfully and optimally implementing tunneling projects and rock mass stabilization around the tunnel. Of course, in some other cases, the two-dimensional analysis is sufficient. Therefore, in this study, two-dimensional and three-dimensional analyses of tunnels in the seismic state have been compared. First, the jointless rock mass is modeled in static and seismic states. Then, step by step, the displacement around the tunnel in two-dimensional and three-dimensional states is weakened by weakening the rock mass. The results show that in strong and joint-less rock masses, there is no significant difference in the results of two-dimensional and three-dimensional analysis, which is the case for both static and seismic analysis, and most of the results of two-dimensional modeling. More than. However, as the rock mass becomes weaker, the difference in displacements in two-dimensional and three-dimensional states becomes noticeable, especially in seismic analysis.