Changes in the acoustic properties of road porous surface with time

The low-noise surfaces such as porous asphalt have become
more frequently used to reduce traffic noise. This method of noise control may
be effective where reductions of the order of a few decibels are required, and
may provide a more economic solution compared to other forms of noise control,
such as noise barriers. The main disadvantage of the porous pavement is its
decreasing acoustic effectiveness over time, caused by dirt blocking the pores
on a road surface. The paper presents the acoustic effectiveness of the two
types of porous road pavements after a few years of use.