Prediction Model for Railway Noise in Consideration of Sound Reflection on Bridge

Abstract

This paper describes a model for predicting wayside noise close to an overpass on Shinkansen railway line. In the development of the model, sound reflection on the bottom surface of bridge should be taken into consideration. The effect of sound reflection was examined in acoustic experiments with scale models. Then, a mirror image source and a correction value due to the reflection on the finite surface were introduced into the prediction model. It was validated by comparing the measured results with the results simulated by the prediction model. It was found by using the prediction model that the mirror image sources corresponding to the noise generated from the lower part of railway cars and the track have a greater influence on the wayside noise.