More Than Just Concrete: Acoustically Efficient Porous Concrete with Different Aggregate Shape and Gradation

Abstract

The interest in the use of resistant acoustic materials has put further attention on the use of porous concrete in the building industry. This work investigates the acoustic properties of four different mix designs of porous concrete obtained with two types of aggregates, that is, normal weight and lightweight aggregates. The assessment of the sound-absorbing performances has been conducted in the small-scale reverberation room (SSRR) at Politecnico di Torino (Italy), in agreement with the procedure indicated in the ISO 354 Standard. For each concrete type, three panel thicknesses, i.e., 20 mm, 40 mm, and 60 mm, were tested. Moreover, different mounting conditions were investigated, considering the combination of single panels in multiple layers, adding an air gap between the panel and the backing, and inserting a layer of rock wool in the air gap itself. The results show weighted absorption coefficients (αw) in the range of 0.30 to 0.75 depending on the thickness and mounting conditions. These encouraging values make these materials useful for efficient practical applications in indoor and outdoor environments.

Acoustic Performance of Porous Mortar and Potential Use for Traffic Noise Mitigation: A Review

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Acoustic Properties of Absorbing Materials

“…Since the mechanism influencing the acoustic performance of aerogel-impregnated blankets is still unclear and there is a lack of studies attempting to explain the measured absorption properties with a valid mathematical model, this paper contributed to this knowledge gap through a simulation that predicts the measured complex acoustic reflection coefficient of aerogel blankets with different filling ratios. The fourth contribution to the Special Issue, by Shtrepi et al [4], is an experimental characterization of the sound absorption performances of "normal weight" and "lightweight" porous concrete aggregates. For each concrete type, three panel thicknesses were tested.…”

Sound-Absorbing Acoustic Concretes: A Review

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