Calculation of noise from railway bridges and viaducts: Experimental validation of a rapid calculation model

The noise emitted by a railway bridge or viaduct under traffic can, in principle, be calculated using finite element techniques that take account of the specific geometry of the bridge, but for high frequencies, where the modal density is large, this can be very computationally intensive. This means that the benefits of performing large parametric design studies are often overshadowed by the time taken to complete them. Here, a rapid calculation model is described for the vibration power transfer from the rail into the bridge that is coupled with the SEA method for vibration power propagation and noise radiation. This relies less on the exact geometry of the bridge and more on its general characteristics. The model has recently been developed to represent the coupling between the rail and bridge at low frequencies and the mobility of the support girder at high frequencies with greater detail. It is used here to evaluate the noise and vibration of a concrete–steel composite viaduct. The predictions are then compared with real experimental noise and vibration data taken from the viaduct under traffic.