Analysis Of The Current Situation Of Outdoor Acoustic Environment And Research On Optimization Strategies In Old Residential Districts At Xi’an

From the 1970 s to the 1990 s,in order to alleviate the problem of rapid urban population growth and the shortage of per capita housing space,most cities across the country built a large number of residential communities with government agencies,enterprises and institutions as the main body.However,due to the limitations of the construction technology and concept at that time,insufficient attention was paid to the acoustic environment problems in the community.Therefore,as the government vigorously promotes the old reform today,how to improve and create a livable and comfortable outdoor acoustic environment in the old community has become a key issue that needs to be considered at the moment.This paper takes typical old communities in Xi’an as the research object.Based on the collation of the existing research results,the current situation of outdoor acoustic environment in typical old communities in Xi’an is carried out using on-site measurements,questionnaire surveys,and computer noise map simulation.Comprehensive and in-depth analysis,and further propose and verify related optimization noise reduction strategies.The ultimate research goal is to improve the overall outdoor acoustic environment quality of old communities in Xi’an.First,after a comprehensive analysis of the characteristics and commonalities of the old communities in Xi’an,a large-scale analysis of major noise sources and subjective questionnaire surveys were carried out on 12 representative typical old communities.Through the subjective evaluation of the interviewees,the four aspects of social characteristics,behavior characteristics,satisfaction with the surrounding environment,and preferences of different sound sources were analyzed concretely,and the characteristics of the main activity groups and their behavioral logic were discovered.Then,from the perspective of the interviewees,a statistical analysis was carried out on the comfort of the community’s internal environment and the preferences of different types of sound sources.The above survey data all give a sufficient factual basis to explain the problems existing in the outdoor acoustic environment of the community.After that,5 sample old communities were further screened for field data testing and research.According to the actual range of the sample cell,select a different number of monitoring points for testing.It mainly focuses on the actual measurement and analysis of the most common noise sources in the two major types of old communities,road traffic noise and social life noise,and their actual impact on the outdoor acoustic environment of the community.And in-depth study of the time distribution and vertical propagation of various types of noise.It is found that the sound pressure level of each monitoring point in the same community often shows huge differences with time and geographical location,and has clear and clear time and location differentiation attributes,and the noise is distributed on the vertical level of multistorey buildings.The above also showed obvious regularity.Finally,this article is based on the simulation of Cadna/A software to test and verify the effectiveness of various noise reduction optimization measures.The simulation analysis of four external urban road traffic noise optimization measures,namely,distance noise reduction,green belt noise reduction,noise barrier noise reduction,and low-noise pavement,was carried out,and the effectiveness of noise barrier noise reduction and road surface noise reduction was found.Limitations of back-distance noise reduction and green belt noise reduction.In addition,optimization design strategies for internal traffic and social life noise continue to be proposed from the perspective of human control and receiving end protection.Finally,in the interior soundscape enhancement design,the interviewees’ preferences for different sound sources are combined to enrich the hierarchy of the outdoor sound environment.Based on the actual situation of the old communities in Xi’an,this paper explores the optimization strategies of the outdoor acoustic environment in the old districts from different aspects.In the context of the pursuit of sustainable development,it provides a valuable theoretical reference for the improvement of the acoustic environment of the old community.