Comprehensive evaluation of sound absorption performance in porous concrete pavement with crushed stone base course

This study comprehensively evaluates the sound absorption performance of porous concrete pavements with crushed stone base layers of varying thicknesses and particle sizes. The noise reduction potential of pavement structures was assessed using the standing wave tube method, and overall sound absorption was quantified via the full-frequency domain average sound absorption coefficient. Results indicate that the presence of a crushed stone base layer substantially enhances sound absorption, with thicker bases providing greater improvements. While particle size and surface layer type also influence absorption, their effects are markedly smaller than that of base course thickness. These findings suggest that optimizing base layer thickness, combined with high-porosity or fine-aggregate surface layers, can effectively improve the acoustic performance of porous concrete pavements, providing practical guidance for noise mitigation in road design.