Environmental implications associated with porous asphaltic concrete : part I and II

English version of 2 contributions to the Wegbouwkundige werkdagen 1992, part 3, p. 1177-1200: Milieu-implicaties ZOAB I and II. Part I deals with questions that have been raised as to whether the use of porous asphaltic concrete (pac) in pavements has affected the production and dispersion of pollutants. Emission of exhaust fumes, leaching behaviour, wear products from vehicles and pavements, water and dirt retention, impact of road cleaning, winter maintenance, and the use of weedkillers on hard shoulders are discussed. Comparisons are made with dense asphaltic concrete (dac). Part II discusses the Pass-by methods, a measuring method for the determination of noise levels of motor vehicles. It is stated that the use of this method can lead to the wrong conclusions. Possibilities are drafted with which the Pass-by method can be improved: measuring on contiguous road sections, use of designated test vehicles, and acoustic trailer measurements. Tests and tests results are described. Comparisons are made between various types of pavement.