Finite Element Analysis for Noise-Reducing of Double-Layer Porous Asphalt Pavement

In order to reduce the harm caused by traffic noise, porous asphalt pavement was widely used in the world. For single-layer porous asphalt pavement easy blocking, double-layer porous asphalt pavement structure was brought out. With the top-layer has smaller porosity, bottom-layer porosity slight greater, this structure has formed an effective dispersed space for noise absorption. The top-layer has a filter effect on large particles. Dust falling into the surface pore was water out due to the bottom-layer porosity was greater. So the double-layer porous asphalt pavement has self-cleaning effect on pore clogging. The numerical simulation for acoustic absorption properties of porous asphalt pavement structure was made with application of finite element method and acoustic-solid coupling model by large-scale commercial software ABAQUS. The noise-reducing feature was analyzed for the double-layer porous asphalt pavement in porosity and thickness combinations and then structural parameters suitable for double-layer porous pavement was proposed. The result indicated that double-layer porous asphalt pavement has better sound absorption for top-layer porosity of 10%, bottom-layer porosity of 25%, top-layer thickness of 2cm and bottom-layer thickness of 4cm.