Mutual influence of parallel tunnels in an elastic medium in the epicentral zone of an earthquake

Abstract

When analyzing the interaction of parallel metro running tunnels in dynamic problems involving wave loading, it is necessary to limit the computational domain using artificial boundaries. This requires the formulation of boundary conditions that ensure transparency for both incoming external waves and internal waves reflected from structural elements. In this paper, exact non-reflecting boundary conditions are proposed. Based on the developed mathematical model, the behavior of tunnel linings under the action of longitudinal and shear waves in the epicentral zone of an earthquake is investigated. The numerical implementation is carried out using the finite element method and the Bathe time integration method. The influence of the distance between circular reinforced concrete linings under longitudinal and shear wave loading is studied. The calculation results demonstrate the high efficiency of the proposed transparent boundary conditions, which makes it possible to reliably investigate wave–structure interaction processes in underground structures under plane strain conditions.