Reliability analysis of traffic noise estimates in Hong Kong

This paper examines the reliability of traffic noise measurement techniques and the noise estimates in Hong Kong. A simulation model making use of the Monte Carlo technique is devised to incorporate the uncertainty in traffic noise estimates in Hong Kong. Traffic flow, traffic speed and traffic composition (in terms of percentage of heavy vehicles) are identified as the key factors influencing the generation of traffic noise. The new equations for estimating the noise descriptors L10, Leq, L50 and L90 were calibrated on the basis of the Hong Kong survey results. The effects of the key factors on traffic noise estimates can be assessed. The probability distribution for each of the key factors is derived with the use of the survey data. The variation on the key factors is due to the sampling error in the survey. The reliability of the traffic noise estimates is obtained from the combined probability distributions of the key factors. The reliability analysis gives the traffic noise estimates with a particular probability or vice versa.