Effects of surface texture on tire-pavement noise and skid resistance in long freeway tunnels: From field investigation to technical practice

Abstract

In order to effectively control tire-pavement noise in long freeway tunnels, this study aims to determine suitable low-noise pavement texture. The main indicators evaluated include texture parameters, A-weighted sound pressure level, octave, sideway force coefficient and the actual unit cost of building single texture. Sound signals at the tire-pavement interface are detected by the OBSI system without the influence of other nearby sources, then acquired by Dewesoft system and sent to a laptop computer for post-processing on Coinv DESPET software platform. The continuous friction tester is used to measure sideway force coefficient on each pavement surface at same vehicle speed. All testing efforts are based on previous investigation sections and two specially constructed long freeway tunnel sections with various specific textures. Afterwards, the technique for order preference by similarity to ideal solution, is adopted for the final comprehensive evaluation. The study found that the freeway tunnel is a hostile acoustic environment. The tire-pavement noise inside the tunnel is about 20 dB(A) higher than the external normal sections, whether it is asphalt pavement or cement concrete pavement. In addition, the longitudinal equidistant groove with large center spacing of 25 cm, not only help eliminates the pumping noise but prevents the side sliding of vehicles, is considered to be an effective technique on the premise considering economic cost. Also note that, the section near the tunnel entrance belongs to the transition zone of tire-pavement noise and a bottom area of skid resistance. The transverse unequal spacing groove can yet be regarded as a suitable choice for this section and wet section inside the tunnel. What is more, an interesting finding is that there is no direct correlation between tire-pavement noise and sideway force coefficient, regardless of groove textures. This means that a quieter pavement texture can be obtained without hindering the skid resistance. In this sense, the findings of this study may provide a little practical reference to create a “quiet, safe,” surface texture suitable for the long freeway tunnels.