Field Investigation of Metro Rolling Noise

This paper presents a field study on railway noise measurement in a tight curve and a tangent track of Tehran Metro Network in Iran. Nowadays as railway and metro tracks often pass through densely populated areas, especially in central parts of big cities, noise is usually the most common reason given for objecting to railway developments. As a result, significant progress has been made in noise control over the last decades. More recently, high interest was given to measuring railway noise and understanding the different sources contributions in order to help reducing global external noise. In this research, sections of Tehran Metro Network, which are located near a high resident people density area with a limited but significant traffic, were selected. In these sections, railway noise seemed to have been tolerated in the past, but is today increasingly being considered as a nuisance for the residents. Noise generated by the railway vehicle was recorded by field tests based on the acoustic standard ISO 3095. Measured noise levels in two different test sections including the tangent track and the curve have been evaluated and compared. Furthermore, metro rolling noise has been detected and separated using band-pass filtering.