The impact of China's traffic noise spectrum on the Single-number-quantities (SNQs) evaluation of airborne sound insulation in the new era

The ISO 717-1 specified the weighted sound reduction index calculation method of airborne sound insulation, also includes two spectrum adaptation terms C and Ctr, to take into account different spectra of environmental and living noises. The reference spectrum for Ctr is A-weighted urban traffic noise, and it is meant for noise sources such as traffic noise (urban road traffic, railway traffic at low speeds, propeller driven aircraft), disco music, and factory emission noise (low and medium frequency noise emissions).It should be noted that the spectra Ctr applied in ISO 717-1 was adopted from the Nordtest Method NT ACOU 061 (Nordtest, 1987).The means of transportation are undergoing great changes, and the characteristics of traffic noises are also changing significantly. Therefore, in order to better resolve the disputes caused by sound insulation and traffic noise in China, it is necessary to explore whether the existing evaluation standards are still applicable to various types of traffic noise. In this paper, the urban traffic noises in China have been measured and analyzed, a new spectrum adaptation terms for airborne sound insulation evaluation was established, and applied to the calculation of sound insulation of several common building components, and its applicability was discussed.