SEISMIC RESPONSE OF SEGMENTED TUNNEL LINER

Abstract

The use of tunnels has expanded in recent years to facilitate traffic, so dependable assessment of the seismic response of tunnel structures is critical in civil and earthquake engineering. Although tunnels are supported by segmental concrete linings, their behavior under the effect of joints is still ambiguous. Previous researches studied the seismic performance of tunnels assuming they are continuous conduits. They didn’t consider the segmental effect, which would lead to variation in obtained results such as internal forces, tunnel liner deformation, and consequently surrounding soil response. This study aims to investigate the segmental tunnels under seismic loads. The numerical tool used in this analysis is Plaxis 2D version 20.0.1.128 finite element software with the Mohr-Coulomb material model. Results show that the existence of joints in tunnels makes tunnels more flexible. As a result, the settlement values increase, and the maximum bending moment in tunnel lining decreases with great values for the same lining thickness to diameter ratio. As for normal force, existing joints have relatively less effect on normal force values.