AVALIAÇÃO DO DESEMPENHO ACÚSTICO DE LAJE NERVURADA COM DIFERENTES COMPOSIÇÕES DE PISOS

Abstract

The development of constructive systems aiming acoustic performance consists in one of the major challenges for the Brazilian civil construction sector. Inefficiencies during the building process are originated, in several cases, from the lack of technical data which qualify the constructive materials, which have been presented to the civil construction market in bigger numbers and also with different characteristics. Among the materials which influence the acoustic performance of a building, it is possible to evaluate the crawlspace systems. In this context, concrete waffle slab are used expressively in the current scenario. Specifically regarding this system, there is lack of validation of its acoustic performance, considering different topping and using plasterboard downgrade, which may be used as components in its constitution. Hence, it was evaluated the performance of a concrete waffle slab whose cavities were filled with EPS regarding the weighed impact sound pressure level (Ln,w) and its sound reduction index (Rw). All the slabs presented a base typology, which corresponds to a concrete waffle slab with filling of the cavities in EPS (with dimensions of 70x70x20 cm) slab mesh thickness of 5 cm and rib of 20 cm, totalizing 25 cm. On the remaining typologies it was used materials and elements as increments in order to assess the acoustic performance. To validate these systems, tests were performed in reverberating acoustic chambers for vertical airborne sound, built following the parameters of ISO 10140-5:2010, at itt Performance, from UNISINOS. It was noted that through the utilization of plasterboard downgrade alongside the application of acoustic covering under the mortar screed, it was obtained a weighed impact pressure level reduction of 43 dB and also an increase in the acoustic insulation of 24 dB, comparing the different typologies.