Speaker
Description
Ground-borne vibration induced by railway traffic is a growing concern in densely populated urban environments. Railway-induced ground-borne noise and vibration prediction tools are valuable assets when implementing or upgrading railway systems, as well as when constructing new civil structures near existing operational lines. Railway-induced vibration simulations are typically computationally expensive due to several factors, including the unbounded and heterogeneous nature of the soil, the moving dynamic loads generated by wheel-rail interaction, and the dynamic coupling between the different subsystems involved. To reduce computational effort, it is commonly assumed that no significant dynamic coupling exists between the track (or track–tunnel) system and the building of interest. However, in situations where the proximity between the tracks and buildings is small, this assumption may no longer be valid. To address this issue, this paper proposes an efficient methodology to simulate the response of strongly coupled track-soil-building or track-tunnel-soil-building systems based on the blocked force concept. The proposed approach consists of first determining the blocked forces at the building-soil interface using a model of the track-soil or track-tunnel-soil system excited by the moving train-track dynamic and quasi-static loads. These forces are then applied to the corresponding track-soil-building or track-tunnel-soil-building system to compute the building vibration response. By avoiding the explicit modelling of moving loads in this second stage of the methodology, the computational procedure is significantly simplified. The methodology is verified with other numerical schemes to ensure its correctness and a measure of its computational efficiency benefits is given.