A Methodology for the Assessment of Underground Railway-Induced Vibrations Based on Radiated Energy Flow Computed by Means of a 2.5D FEM-BEM Approach

摘要

In this paper, a comprehensive numerical approach formulated in the two-and-a-half dimensional domain (2.5D) for modelling track/tunnel/soil systems in the context of ground-borne railway-induced vibration problems considering a full-space model of the soil is proposed. The approach consists of a coupled finite element-boundary element method (FEM-BEM) of the tunnel/soil system, a semi-analytical model of the track, a multibody model for the vehicle and a model for the vibration propagation in the soil based on semi-analytical solutions of a cylindrical cavity in a full-space. Since this methodology uses finite elements (FE) to model the tunnel structure, its modelling detail is higher than previously developed methodologies dedicated to computing the vibration energy flow radiated by underground railway infrastructures, as they are based on semi-analytical modelling of the tunnel structure. An application of the methodology for studying the efficiency of using one accelerometer for assessing vibration mitigation measures is presented.