Comparative Study of Acoustic Performance of Concrete Blocks with Different Compressive Strengths

Acoustic quality has become an increasingly important requirement in Brazilian construction, especially after the introduction of performance standards such as ABNT NBR 15575: 2021. However, few studies have specifically compared the acoustic performance of concrete blocks with similar characteristics, considering the variation in compressive strength, which impacts properties such as density, porosity, and rigidity, directly influencing the material's ability to isolate or transmit sound. To address this gap, a study was conducted in 2022 at a residential development in Guarulhos, SP. In situ measurements were taken of airborne sound insulation between units, specifically focusing on situations where one of the rooms is a bedroom. The measurements were conducted in 9 internal vertical partition systems made of 14x19x39 cm concrete blocks, with compressive strengths ranging from 6 to 20 MPa. The analysis considered factors such as workmanship quality, block material, and finishing. The results revealed significant variations in acoustic performance among blocks with different compressive strengths. It is hypothesized that inconsistencies in workmanship quality may have influenced these differences. This study contributes to a deeper understanding of the acoustic behavior of concrete blocks, and future research will seek to compare these empirical findings with performance predictions from computational simulation software.