一种路面吸声系数的现场测试方法

为了在不破坏路面结构的条件下得到路面的吸声性能,解决工程建成后的验收和测试问题,进行了阻抗管的结构改造,并搭建了阻抗管路面测试系统;以道路路面为研究主体,研究了密封材料对测试结果的影响;运用传递函数法原理现场测试路面的吸声系数,通过比对现场实测结果与实验室路面样品测试结果,评价阻抗管现场测试系统的可靠性和测试方法的可行性。研究结果表明,用橡皮泥做密封材料时,密封效果较好;路面测试系统现场实测吸声系数曲线基本一致;现场实测吸声系数与路面样品吸声系数差值不超过0.04,属于误差允许范围内,两组吸声系数在800 Hz以上比较吻合,差值小于0.002,在250~630 Hz范围内差值在0.02~0.038之间,且在此频率范围内路面实测吸声系数低于实验室测试结果。

A field test method of pavement absorption coefficient

In order to get the pavement sound absorption coefficient without damaging the pavement structure, and to solve the problem of acceptance and test after the completion of some projects, the impedance tube structure is remolded, and the impedance tube test system is constructed. In the test, the pavement is chosen as the research subject, the influence of sealing material on the test results is studied. The pavement sound absorption coefficient is tested according to the principle of the transfer function. Meanwhile, the feasibility of the measurement method and reliability of the measurement system with impedance tube was evaluated by comparing the field measurement results with the laboratory results. The study results show that there is good sealing effect when the silly putty is used as seal material. The field measured sound absorption coefficient curves look alike. The difference of field measured sound absorption coefficient with the sound absorption coefficient of the sample pavement is less than 0.04 which is in the range of acceptable error, and they match better at the frequency more than 800 Hz, where the difference is less than 0.002. In the 250-630 Hz frequency range 250-630 Hz, the sound absorption coefficient of field measurement is lower than that that tested in laboratory, and the difference is between 0.02~0.038.