Effect of pore characteristics on the sound absorption of pervious concretes
Paulo Chagas Rodrigues, Nállyton Tiago de Sales Braga, Euler Santos Arruda, Luciana de Nazaré Pinheiro Cordeiro, Gustavo da Silva Vieira de Melo
Abstract
The objective of this paper is to evaluate how the properties of pores affect the sound absorption of pervious concretes. To this end, nine mixtures of pervious concrete were prepared with pebbles as coarse aggregate, controlling cement consumption and water/cement ratio to vary the porosity properties of the mixtures. The specimens were tested in a reduced-scale reverberation room to determine the sound absorption coefficient for diffuse incidence. As a result, correlations were obtained between the properties of internal pores and the sound absorption at medium and high frequencies, while the properties of superficial pores were related to the absorption at lower frequencies. An optimum value of w/c ratio of 0.32 and cement paste content of 0.27 and 0.29 were found to improve the sound absorption of pervious concrete.