Laboratory Measurement Of Sound Insulation Loudness Difference Of Building Components

With the continuous development of China's construction industry,the types and construction methods of building partitions are becoming more and more diversified,and the evaluation standard of air sound insulation performance of building components is getting more and more attention.The sound insulation performance of enclosure structure is one of the important issues in the research and design of building acoustics.According to GB / T50121-2005,the weighted sound insulation capacity is used to evaluate the air sound insulation performance of building components.However,it is found that the sound insulation parameters based on sound pressure level difference are different from the sound insulation effect of subjective feeling.Appropriate sound insulation evaluation parameters should be able to fully reflect the change of subjective sound insulation perception of different types of noise after sound insulation.In this paper,the sound insulation loudness level difference,a new parameter for the evaluation of building component's air sound insulation,is studied.The practicability of sound insulation loudness level difference in the evaluation of building component's air sound insulation performance is mainly studied by means of laboratory measurement and subjective sound evaluation test.Firstly,three main loudness models,Steven loudness model,Zwicker loudness model and Moore loudness model,are analyzed in this paper.Based on Zwicker loudness theory,the sound insulation loudness difference model is established as a parameter for evaluating the sound insulation performance of building components to evaluate the sound insulation effect of building components.Then,the measurement method of loudness grade parameter is established in the laboratory.In the air sound insulation experiment of the State Key Laboratory of Subtropical Building Science,South China University of technology,three kinds of common building components,aerated concrete light exterior wall,double-layer glass window component and three-layer glass window component,are taken as the research objects.The loudness level difference of components is measured under three types of sound sources and five levels of sound source chambers.Compared with the weighted sound insulation,the applicability of sound insulation loudness difference in the sound insulation evaluation of building components is studied.Finally,the subjective annoyance degree is evaluated by recording and playback in the laboratory,and the annoyance degree caused by different noise samples is evaluated by usingthe research methods of rating method and paired comparison method.The results show that the sound insulation evaluation parameters based on loudness difference have a higher correlation with the subjective annoyance perception of human ear.The sound insulation evaluation parameter based on loudness level difference is different from the single value evaluation value of weighted sound insulation in China.Weighted sound insulation is an evaluation parameter based on sound pressure level difference.The weighted sound insulation has nothing to do with the type of sound source and the level of noise level,while the difference of sound insulation loudness reflects the decrease of subjective loudness sense of people,and has something to do with the level of sound source and the type of sound source.The sound insulation loudness level difference can reflect the influence of sound insulation frequency characteristics and noise characteristics on the subjective sound insulation effect of components.The sound insulation loudness level difference is more consistent with the subjective perception when evaluating the sound insulation effect of components.