Research And Application Of Sound Absorption Performance Of Fine And Porous Asphalt Mixture

With the continuous development of urbanization,traffic noise pollution has been the main problem and continuous challenge of environmental governance of Governments r management departments.Traffic noise will not only cause people’s mood fluctuation,upset and psychological pressure,but also increase the risk of hypertension,cardiovascular disease and some other health disease.Low noise pavement as a new type of environment-friendly pavement to reduce tire/pavement noise from sound source,with the most cost-effective,the least adverse impact on the surrounding environment and other unique advantages under the same noise reduction requirements,has a very high research value.This paper discusses the material and structural characteristics of several low-noise asphalt pavement with significant noise reduction capacity at home and abroad and the main noise reduction methods of tire/pavement noise and summarizes the existing methods of tire/pavement noise detection method.We choose to use fine aggregate to get smooth texture to reduce the vibration noise of the tire and porous structure to increase the sound absorption performance of the mixture,that is,the “fine-grained,porous” research ideas.In order to meet the requirements of sound absorption performance and road performance,the design of target mix ratio is determined by controling the voids ratio of compacted coarse aggregates to make the mixture framework structure,adjusting the key sieve hole pass rate to get target voids,conducting the leakage and raveling loss test to determine the optimum asphaltaggregate ratio.The single factor analysis result of fine and porous asphalt mixture shows that the sound absorption performance of PA10 is better than that of PA07 asphalt mixture.Increasing the voids(or connecting voids)can improve the sound absorption performance of porous asphalt mixture significantly.The peak corresponding frequency of the sound absorption coefficient of the mixture specimen showed a strong correlation with the thickness of the specimen.Multifactor analysis of fine granular porous asphalt mixture by grey theory shows that the peak value of porous asphalt mixture suond absorption coefficient curve is mainly affected by the connected voids,and the voids or connected voids have a great influence on the mean value of the sound absorption coefficient.The conversion of porous asphalt mixture based on the peak of sound absorption coefficient shows that the noise reduction level depends more on the voids of porous asphalt mixture than on the nominal maximum particle size and the thickness of the mixture specimen.Comparing the sound absorption performance of double-layer and singlelayer with equal thickness porous asphalt mixture,it is found that the "two peak phenomenon" will appear in the double-layer porous asphalt mixture with large voids within the test frequency range.And the sound absorption performance of double-layer porous asphalt mixture is significantly lower than that of single-layer mixture with equal thickness.The road performance of PA10 asphalt mixture were excellent with different voids and good frost resistance.The deflection of road surface and the horizontal tensile stress of basement reduced after paving PA10 porous wearing layer.The key construction technology is put forward in the process of paving the test section.The road performance of the mixture and the results of the field test meet the requirements of the specification.and the effect of noise reduction is obvious.