Influence of Soil Properties and Model Parameters on Vibrations Induced by Underground Railways for Deep Stratified Alluvial Deposits

Thin-layer method (TLM) is presented and applied to model the ground vibrations induced by underground railways located in deep stratified soft-soil deposits. The numerical model is calibrated by vibration levels recorded from arrays of accelerometers placed both in the railway tunnel and on the ground surface in Shanghai metro. Then a parametric study is performed to investigate the effect of dynamic soil properties on the vibration levels calculated using TLM. These properties include the soil material damping and Poisson ratio. Lastly, the study is focused on the influence of model parameters, such as model dimensions. Vibration levels and transfer functions on ground surface is calculated using different parameters for comparison. Calculation results illustrate that both the dynamic soil properties and model parameters have noticeable influence on modeling free-field vibrations from underground railways.