@article {Park:2019:0736-2935:6302,
title = "Estimation of normal incidence sound absorption coefficient of porous asphalt mixture by its porosity and the new particle distribution index",
journal = "INTER-NOISE and NOISE-CON Congress and Conference Proceedings",
parent_itemid = "infobike://ince/incecp",
publishercode ="ince",
year = "2019",
volume = "259",
number = "3",
publication date ="2019-09-30T00:00:00",
pages = "6302-6312",
itemtype = "ARTICLE",
issn = "0736-2935",
url = "https://ince.publisher.ingentaconnect.com/content/ince/incecp/2019/00000259/00000003/art00034",
author = "Park, Hee Jin and Iwaiwai, Shigeo",
abstract = "Porous asphalt pavement with a surface layer made by porous asphalt mixture (PAM) is widely prevalent to reduce tire/road noise. It is important to recognize an acoustic absorption effect of the surface layer ( PAM medium without its direct measurement at the design stage before construction
of the pavement . The acoustic absorption effect of PAM medium is usually evaluated by the normal incidence sound absorption coefficient (NISAC). In this paper, firstly, approximate expressions which are transcribed the phenomenological absorber model derived by Hamet et al with the porosity
of PAM medium as a variable is derived for evaluating the NISAC of PAM medium. Then, it is shown that the NISAC of PAM medium can be estimated by only two factors, the targetry porosity and the thickness of PAM medium without its direct measurement. Secondly, the PDI is calculated by geometry
of the particle size distribution compatible with the targetry porosity and the is obtained by the ratio of the area of the NISA C zone of PAM medium to the area of the complete absorption coefficient zone in the figure of the relationship between frequency and the NISAC in the certain frequency
period are proposed f or th e quantitative evaluation of the NISAC of PAM medium From the result of considerations of the relationship between the PDI and the , it i s clear that the NISAC of PAM medium can quantitative ly evaluate by the PDI and the at the design stage.",
}