ABSTRACT
Underground structures, including tunnel, tend to receive lower seismic impact rather than on surface structures. However, seismic waves from earthquakes shouldn’t be underestimated because they can still damage a well-designed underground structure on certain scale. Seismic waves, including their propagation, can be quite complex since they directly relate to uncertainty. Seismic-related research is developing periodically, but research specifically observing the impact on different propagation directions is still uncommon. Therefore, a finite difference method commercial program was used in this research to observe the impact on tunnels by analyzing the bending moment and normal force on segmental tunnel linings due to various propagation directions. Moreover, the study examined the outcomes of applying various joint stiffness ratios from 0.1 to 1.0 with 0.1 intervals. The findings prove that using less stiff joints is desirable for tunnels subjected to dynamic loads because they allow certain displacement for the structure, which reduces the bending moment caused by the seismic effect. It has also been proven that diverse effects on tunnels may arise from different propagation directions, with 2-directional waves causing damage to the tunnel structure the most.
