Determination of mechanical properties and water susceptibility of low-noise road surfaces

Abstract

Nowadays, there is a need to reduce noise pollution due to the tyre-pavement interaction, especially in densely-populated areas, such as the Netherlands, where noise pollution is a major concern. A solution to this problem is the development of pavement surfaces with improved noise reduction characteristics. Previous attempts to develop low-noise pavement surfaces were not successful, mainly due to their poor mechanical performance and low durability. In this research the mechanical performance of three different low-noise pavement surface materials is investigated. The study was part of the Ultrastil Wegdek (USW) project in the Netherlands. The materials were evaluated with respect to their moisture susceptibility, stiffness, cohesive strength and bonding with the underlying layer. For three different low-noise road surfaces (LNRS), the stiffness was evaluated by means of dynamic modulus tests. Furthermore, indirect and direct tensile tests were carried out after long- and short-term moisture conditioning to estimate strength degradation. The interlayer bond strength was determined using uniaxial tension tests at dry and wet conditions. To evaluate the bond characteristics, also two-layer porous asphalt systems were tested as reference materials. The results show high difference in their properties as a result of the mixture composition. Especially, considering the effect of moisture is of paramount importance for these highly open-graded mixtures.