Evaluation of efficiency of Under Sleeper Pad by focusing on dynamic behavior of track

Abstract

Since resilient sleepers were applied to the railway lines, solid rubber has been mainly used for under sleeper pad (USP). Recently, cellular rubber is newly used for the material of USP. The authors focused on dynamic viscoelasticity of the USP and evaluated effect of that on track dynamic response and ballast settlements by using numerical simulations. The simulation results show that the viscoelasticity of USP doesn’t effect on reducing the sleeper bottom loading but ballast vibration acceleration. Then those results show that the ballast settlement decrease accompanied with the increasing of the viscoelasticity of USP.