ACOUSTIC PERFORMANCE OF TRAFFIC NOISE BARRIERS. A STATE OF THE ART REVIEW

For many years barriers have been erected alongside major roads to screen residential areas from high levels of traffic noise. A very wide range of materials have been used including wood, steel, aluminium, concrete and acrylic sheeting. Some of these designs have absorptive facings on the traffic side which reduce reflected sound and are claimed to improve screening. Barriers over 8 m in height have been used for some applications and novel capped barriers, angled barriers and vegetative barriers have been tested. This review summarizes the available information on the acoustic performance of various types of barrier and discusses the scope for cost effective application. The paper highlights the problem of meteorological factors which may influence the results of field measurements and recommends the need for further testing under carefully monitored conditions. The use of computer programs to aid the design of cost effective barriers is also described. (A) This paper was presented at Eurosymposium, Delegation traffic noise in urban areas, May 1992, Nantes, France.