Noise reduction of road surfaces with horizontal grinding

Many low-noise road types make use of the surface property to reduce the tyre-road noise by incorporating specific texture designs. However, the initial road texture of these surfaces deteriorates over the years, which progressively reduces the noise-attenuating effect. Furthermore, other types of road surfaces achieve their noise reduction in higher frequency bands by introducing porosity; this, however, often increases surface roughness, resulting in elevated noise levels in lower frequency bands. To address these issues, multiple research studies have investigated the potential improvement of the acoustic properties of surface layers by horizontal grinding of the texture to restore or improve noise-reducing effects. To achieve the desired acoustic effect, it is necessary to determine the optimal grinding intensity. This highly depends on the initial texture of the surface and must be determined individually for each road segment. Without a targeted approach, random grinding can lead to unsatisfactory results. The role of the acoustics specialist is essential to design (by acoustic simulation) the target texture based on the initial road condition (texture measurement) and monitor the achieved texture during the grinding process to ensure quality. Incorporating this process of texture design and control is essential to achieve optimal noise reduction.