Sound Absorption Property of Cement Block Containing Rice Husk Ash

Abstract

This paper presents the study of sound absorption properties of two types of cement blocks, i.e., the cement block containing rice husk ash (RHA) and the RHA cement block when installed with glass wool insulation. Rice husk ash is a by-product of the process of burning rice husk to generate electricity. RHA was mixed with Portland cement Type 1 at 20% by weight of binder. The water-to-binder ratio was 0.6, and the binder-to-fine aggregate (sand) ratio was 1:2.75 by weight. The sound absorption properties of the RHA cement blocks was then compared with the reference cement blocks widely used in the construction industry. It was found that RHA can effectively enhance the sound absorption performance of cement blocks. The sound absorption coefficients of RHA-based cement blocks were significantly higher than those of the reference cement blocks, especially at frequencies higher than 6,000 Hz. Furthermore, installation of glass wool insulator could also increase the sound absorption coefficient, in particular at lower frequency range up to 4,000 Hz. In summary, the use of RHA to replace Portland cement at 20% by weight of binder is applicable for the manufacture of cement blocks and helps improve the sound absorption property of the blocks.