沥青混合料吸声性能

Sound Absorption Performance of Asphalt Mixture

采用双传声器传递函数法测试骨架密实型橡胶沥青混合料(SDARC-13)、沥青混凝土混合料(AC-13)、玛蹄脂碎石沥青混合料(SMA-13)与开级配抗滑磨耗沥青混合料(OGFC-13)的吸声系数,研究了各沥青混合料级配类型、空隙率、厚度和噪声频率对其吸声性能的影响.结果表明:OGFC-13沥青混合料空隙率大,吸声系数的峰值最大,厚度为6cm的OGFC-13沥青混合料的吸声系数峰值可达0.83,表现出良好的吸声性能;掺入橡胶粉能够提高沥青混合料的吸声性能,SDARC-13沥青混合料的吸声系数峰值高于AC-13和SMA-13沥青混合料;增加沥青混合料厚度会使其吸声系数峰值对应的频率向低频方向移动,说明沥青混合料厚度的增加有利于沥青混合料对低频率噪声的吸收.

The sound absorption coefficients of skeleton dense asphalt mixture(SDARC-13),AC-13,SMA-13 and open graded friction course(OGFC-13)asphalt mixture were tested by dual microphone of transfer function method.The influence of grade distribution type,air voids of asphalt mixture,thickness of specimen and noise frequency on the sound absorption performance of asphalt mixture was investigated.It is shown that the peak value of sound absorption coefficient of OGFC-13 asphalt mixture of large air void is higher than that of other asphalt mixtures.The sound absorption coefficient of OGFC-13 asphalt mixtures of 6 cm thickness can reach a peak of 0.83,showing a good sound absorption performance.The sound absorption coefficient of the SDARC-13 is higher than that of AC-13 and SMA-13.The increase of the thickness of asphalt mixture will move the peak of acoustic absorption coefficient to the low frequency.It indicates that increase of material thickness is beneficial to the absorption of low frequency noise.