Study On Single-number Quantities Of Sound Insulation Evaluation Based On Psychoacoustic Parameters

With the continuous improvement of living standards,people pay more and more attention to the quality of human settlements.The sound insulation performance of buildings is an important factor affecting the livable environment.At the beginning of this century,China issued the standard GB/T 50121-2005’Rating Standard of Sound Insulation in Buildings’,which stipulates that the sound insulation performance of building components is evaluated by weighted sound insulation R_w.Followed by the introduction of GB/T50118-2010’Code for Design of Sound Insulation of Civil Buildings’,there are mandatory provisions for sound insulation and noise reduction of residential buildings,but there are still a lot of sound environment standards but still disturbing the people.This may be related to the fact that the sound insulation evaluation does not conform to the subjective feeling.Therefore,it is an urgent problem to find a single value of sound insulation that can be more consistent with the subjective feeling.In this paper,the air sound insulation of common building components is selected as the research object.Combined with the loudness calculation model,the acoustic parameters such as loudness and psychoacoustic annoyance in sound quality evaluation are used to analyze the sound insulation frequency characteristics of building components and the correlation between sound insulation single value and subjective perception in different frequency bands.The correlation between objective sound insulation evaluation index and subjective loudness and noise annoyance is explored,which provides a basis for studying the single-number quantities of sound insulation evaluation that can fully reflect subjective feelings,so as to solve the problem that the sound insulation performance of buildings meets the requirements of physical indicators but does not meet the psychological feelings of residents.The main research contents and results are as follows:1.This paper investigates civil buildings,selects common building components,calculates the sound insulation frequency characteristics and sound insulation quantity of common building components by using sound insulation prediction theory,and measures the sound insulation performance of components in the laboratory to verify the calculation results.In order to obtain more different sound insulation frequency characteristics,the sound insulation of building exterior walls with dry hanging stone and aluminum curtain walls was also measured in the laboratory.2.Nine kinds of sound insulation single-number quantities with different corrections and different frequency ranges are calculated.In order to obtain more data samples,the air sound insulation of different components is translated by±2d B in this study.Then,a series of sound insulation filters with different sound insulation are set up to simulate the process of outdoor noise source passing through the building components to the interior.The loudness level difference of three kinds of noise sources after different component sound insulation translation is calculated respectively.The correlation between the single value evaluation index of building component sound insulation and subjective loudness is analyzed from the aspects of sound insulation frequency characteristics of building components and frequency spectrum characteristics of noise source signal.The results show that there is no single-number quantity that is fully applicable to evaluate the loudness level difference caused by various noise sources.Compared with R_w,R_w+C and R_w+C_tr series may be more consistent with people’s subjective feelings.The large slope of the straight line fitted by the sound insulation amount means that the uncertainty of sound insulation will be greater.If the low-frequency sound insulation performance fails to improve synchronously with the high-frequency sound insulation performance,the improvement of the single-number quantity of R_w+C_tr will not be ideal,resulting in a larger loudness level difference,that is,the subjective sound insulation effect is not ideal.3.In order to further explore the correlation between objective sound insulation evaluation index and subjective perception,the psychoacoustic annoyance of three kinds of noise sources after different component sound insulation translation is calculated by using the same research method as the loudness level difference,and the correlation between the single-number quantities evaluation index of building component sound insulation and psychoacoustic annoyance is analyzed.The results show that the influence of noise sources with different spectrums on subjective feelings is inconsistent.The white noise with middle and high frequency has a great influence on the loudness difference,and the traffic noise with middle and low frequency has a great influence on the psychoacoustic annoyance.The greater the sound insulation of the building component,the better the noise reduction effect,but the subjective perception of the degree of psychoacoustic annoyance is not necessarily smaller.