Current levels of noise in an urban environment

This paper test sound absorption coefficient of different air voids specimen in reverberation chamber and low noise pavement field testing, which gets main frequency band range of pavement noise is 315~5000Hz, noise arrives at the peak of about 500Hz; the relationship of microphone height and sound pressure level is not obvious; the porous asphalt mixture which air voids is more than 20% has the upper sound absorption coefficient at the frequency of 400~1000Hz, and its noise reduction effect is obvious; There is a linear relationship between the air voids and the maximum absorption coefficient of asphalt mixture, increasing air voids can cause larger absorption coefficient; sound-absorbing property of the low noise asphalt pavement is one of the dominant mechanism of mitigation traffic noise.

Research on Correlation between Urban Low-Noise Pavement Air Voids and Sound Absorption Coefficient

This article describes the present legal measures in Great Britain against noise, the legal powers of local planning authorities to control noise, and the principles of physical planning against noise. The maximum permitted sound levels in urban and rural areas are mentioned together with their effect on airports, aircraft, traffic and traffic management methods of insulating buildings and houses, and their effectiveness in noise reduction are tabulated. /TRRL/

G H VulKan

Papers

The control of noise