Numerical method for seismic analysis of submerged floating tunnels

Abstract

The purpose of this study is to develop the formulation for 3D hydroelastic analysis of tension leg type submerged floating tunnel (SFT) under seismic ground motion and evaluate numerical solutions for the dynamic response of SFT in time domain. In order to consider fluid-structure interaction, we linearize the Morison equation and apply in terms of hydrodynamic force from relative motion between structure and ground motion. We demonstrate the numerical procedure to solve the problem by finite element discretization of the equation of motion. Continuum mechanics based 3-D beam element is applied to the tunnel modeling. Then, we conduct numerical analysis to the several kilometers SFT model and discuss the structure dynamic response of numerical results.