Effect of Aggregate Size and Gradation on the Ceramsite Sound-Absorbing Materials

Abstract

In this paper, the effect of ceramsite aggregate size and gradation on the sound absorption and mechanical properties of the materials were studied and the relationship between material’s pore structure and its sound absorption were discussed. It can be found from the results that the sound absorption and mechanical properties of the ceramsite sound-absorbing materials increase with the content of the fine ceramsite increased due to the decrease of the median pore diameter of the ceramsite sound-absorbing materials where the improvement of the sound absorption at the high frequency band is more significant suggesting that fine pores have a better sound-absorbing effect for high-frequency noise. Higher effective porosity doesn’t mean better sound absorption, because materials with coarse pores have shorter internal routes for sound waves and less friction during sound waves passing through pores, which conversely decreases the material’s sound absorption. Ceramsite with higher internal porosity and more uniform pore diameter distribution can produce materials with better sound absorption.