Noise Sensitivity Analysis of a Two-Stage Baseplate Fastening System

A study is presented into the sensitivity of rolling noise to design changes in a two-stage baseplate rail fastening system. The focus is on the influence on the rolling noise of three parameters of the fastening system: the stiffnesses of the railpad and the baseplate pad and the thickness of the baseplate that determines its mass and sound radiation ratio. The TWINS model is adapted by introducing the baseplate vibration and sound radiation using results from an experimentally verified 2.5D finite element model. Based on the simulations, an optimum railpad stiffness is identified of around 500 MN/m, based on a baseplate pad stiffness value of 80 MN/m. The thickness of the baseplate has only a small effect on the total rolling noise.