Traffic noise exposure of high-rise residential buildings in urban area

Traffic noise distribution characteristics of high-rise buildings along ultra-wide cross section highway with multiple noise reduction measures

Nowadays, ultra-wide cross section highway is a hotspot in construction and brings some unique noise distribution characteristics. In this work, we further investigate noise distribution characteristics of diverse building layouts along ultra-wide cross section highway in Guangdong Province with multiple noise mitigation measures. By the aid of vehicle noise emission model and noise mapping, the influence of high-rise building layouts and shielding in the urban planning on noise mitigation is also considered. Some key findings are summarized as follows: (1) Under the same distance, the noise level of non-frontage building facades is higher than frontage building facades. After taking noise reduction measures, the noise reduction effect of non-street-facing building facades, buildings facing the road, and buildings at a long distance to the road is greater than street-facing building facades, buildings sideways to the road, and buildings at a short distance; (2) the distribution trend of insertion loss (IL) of non-frontage buildings is influenced by the height of the frontage buildings. Specifically, the trend of insertion loss first increases and then decreases as the floor rises when the height of non-frontage buildings is higher than frontage buildings. Comparatively, the trend of insertion loss decreases as the floor rises when the height of non-frontage buildings is equal to frontage buildings; (3) when double noise reduction measures are implemented, the noise distribution trend in buildings is similar to that observed with individual noise reduction measure, where the difference between both is only 0.6 dB(A). Thanks to the high representativeness of the case area, this work can provide some design guidance for the urban planning and the selection of noise reduction measures along the ultra-wide cross section highway.

Characterization of soundscape assessment in outdoor public spaces of urban high-rise residential communitiesa)

Soundscape perceptual models were developed in various contexts. However, as the outdoor public space in high-rise residential communities differs in terms of space planning and management, the soundscape perceptual characteristics are still unclear. In this study, an on-site survey was conducted to obtain the perceptual dimensions of soundscape in outdoor public spaces in urban high-rise residential communities based on evaluations of residents. Meantime, the soundscape of the space in different community layouts were compared. It was found that: (1) Four dimensions of outdoor soundscape in high-rise communities were extracted, namely Relaxation, Communication, Quietness, and Spatiality. The first three dimensions were positively correlated with overall soundscape satisfaction significantly. (2) Relaxation was mostly correlated with dominance of noise; Communication and Quietness were primarily related to sounds from human beings. (3) Lower traffic noise and higher levels of human sounds were perceived in enclosed communities, resulting in higher Relaxation and lower Quietness scores in outdoor public spaces in enclosed communities than non-enclosed ones. These findings evoke insights into the understanding of soundscape assessment in different contexts, and provide implications for sound environment design in urban high-rise communities.

Traffic noise in the bedroom in association with markers of obesity: a cross-sectional study and mediation analysis of the respiratory health in Northern Europe cohort

BACKGROUND

Previous research suggests an association between road traffic noise and obesity, but current evidence is inconclusive. The aim of this study was to assess the association between nocturnal noise exposure and markers of obesity and to assess whether sleep disturbance might be a mediator in this association.

METHODS

We applied data from the Respiratory Health in Northern Europe (RHINE) cohort. We used self-measured waist circumference (WC) and body mass index (BMI) as outcome values. Noise exposure was assessed as perceived traffic noise in the bedroom and/or the bedroom window's location towards the street. We applied adjusted linear, and logistic regression models, evaluated effect modifications and conducted mediation analysis.

RESULTS

Based on fully adjusted models we found that women, who reported very high traffic noise levels in bedroom, had 1.30 (95% CI 0.24-2.37) kg/m² higher BMI and 3.30 (95% CI 0.39-6.20) cm higher WC compared to women, who reported no traffic noise in the bedroom. Women who reported higher exposure to road traffic noise had statistically significant higher odds of being overweight and have abdominal obesity with OR varying from 1.15 to 1.26 compared to women, who reported no traffic noise in the bedroom. For men, the associations were rather opposite, although mostly statistically insignificant. Furthermore, men, who reported much or very much traffic noise in the bedroom, had a statistically significantly lower risk of abdominal obesity. Sleep disturbance fully or partially mediated the association between noise in bedroom and obesity markers among women.

CONCLUSION

Our results suggest that self-reported traffic noise in the bedroom may be associated to being overweight or obese trough sleep disturbance among women, but associations were inconclusive among men.

Statistical and spatio-temporal analyses of noise pollution level and its health impact

Due to rapid urbanization and exponential growth in transportation; traffic noise has become a major area of concern. Noise not only disturbs our day-to-day life but also have severe adverse health effects over humans which further may lead to mortality. This paper focuses on the behavior of noise levels of Lucknow city over a decade and establishes its correlation with impact on human health in terms of annoyance and sleep disturbance. Apart from L_eq, different noise parameters like L₁₀, L₅₀, L₉₀, Traffic Noise Index (TNI), Noise Pollution Index (NPI), and Noise Climate (NC) have also been analyzed to understand the variation of noise. At all the locations, the noise level has been found exceeding their prescribed standards during day time and night time except at Amausi. Out of nine locations, TNI was found to be exceeding at three locations during day time and NPI exceeding at one location. However, during night time both values of TNI and NPL were observed within the limit at all the locations. From the noise map of the city during day time and night time, among all sampling locations, Charbagh has been found to be worst affected by noise pollution. A strong positive correlation has been observed among the total population, vehicular count, and day and night time noise data, which directly contribute to a higher percentage of sleep disturbance and annoyance among residents. Due to the increase in noise levels over a period of time, almost four times the population get affected by high annoyance and almost double the population get affected by sleep disturbance.

Environmental noise and health in low-middle-income-countries: A systematic review of epidemiological evidence

Evidence of the health impacts from environmental noise has largely been drawn from studies in high-income countries, which has then been used to inform development of noise guidelines. It is unclear whether findings in high-income countries can be readily translated into policy contexts in low-middle-income-countries (LMICs). We conducted this systematic review to summarise noise epidemiological studies in LMICs. We conducted a literature search of studies in Medline and Web of Science published during 2009-2021, supplemented with specialist journal hand searches. Screening, data extraction, assessment of risk of bias as well as overall quality and strength of evidence were conducted following established guidelines (e.g. Navigation Guide). 58 studies were identified, 53% of which were from India, China and Bulgaria. Most (92%) were cross-sectional studies. 53% of studies assessed noise exposure based on fixed-site measurements using sound level meters and 17% from propagation-based noise models. Mean noise exposure among all studies ranged from 48 to 120 dB (L_eq), with over half of the studies (52%) reporting the mean between 60 and 80 dB. The most studied health outcome was noise annoyance (43% of studies), followed by cardiovascular (17%) and mental health outcomes (17%). Studies generally reported a positive (i.e. adverse) relationship between noise exposure and annoyance. Some limited evidence based on only two studies showing that long-term noise exposure may be associated with higher prevalence of cardiovascular outcomes in adults. Findings on mental health outcomes were inconsistent across the studies. Overall, 4 studies (6%) had "probably low", 18 (31%) had "probably high" and 36 (62%) had "high" risk of bias. Quality of evidence was rated as 'low' for mental health outcomes and 'very low' for all other outcomes. Strength of evidence for each outcome was assessed as 'inadequate', highlighting high-quality epidemiological studies are urgently needed in LMICs to strengthen the evidence base.

Study on prediction in far-field aerodynamic noise of long-marshalling high-speed train

It is still difficult to conduct numerical calculation of the aerodynamic noise of full-scale, long-marshalling, high-speed trains. Based on the Lighthill acoustic analogy theory, the aerodynamic sound source of the high-speed train is equivalent to countless micro-vibrating sound sources. An acoustic radiation model of the dipole sound source of high-speed trains is established, and a method to predict the aerodynamic noise in the far field of long-marshalling high-speed trains is proposed. By this method, combined with numerical simulation technology, the flow field, noise source, and far-field noise characteristics of high-speed trains with different marshalling numbers are studied. The improved delayed detached eddy simulation method is used for flow field calculation, to obtain aerodynamic noise source information regarding the surface of high-speed trains. The numerical calculation method is verified by wind tunnel testing. The results show that the flow field and noise source characteristics of high-speed trains with different marshalling numbers are similar. The greater the length of the train body, the longer the trailing distance of the train wake, and the stronger of a surface noise source the tail car becomes. The spatial distribution characteristics of aerodynamic noise in the far field of high-speed trains do not change significantly with the length of the train body, but the magnitude of the sound pressure level will increase with the increase in length of the train body. The middle car body parts of high-speed trains with different marshalling numbers have similar noise distributions and sound pressure levels. Based on the noise calculation results of the 3-marshalling high-speed train, the far-field noise of the 5-marshalling and 8-marshalling train models is predicted and found to be in good agreement with the far-field noise of the actual train model. The differences in average sound pressure level are 1.01 dBA and 1.74 dBA, respectively.

Noise pollution and effectiveness of policy interventions for its control in Kathmandu, Nepal

In Nepal, much emphasis has been given to the pollution of air, water, and solid waste both in terms of research and policymaking. Noise is an ignored pollutant, yet a growing public health concern in Kathmandu. This study is aimed at making an assessment of noise pollution in Kathmandu and study the effectiveness of the enforcement of noise standards and No Horn Regulation to control noise pollution. The study was conducted in 23 locations of four different zones (high traffic, low traffic, commercial, and residential) where 12 sites were considered for evaluating the effectiveness of No Horn Regulations. Noise level was studied at five different times of the day using a sound level meter to compute maximum, minimum, equivalent, and average noise level. This study concludes that (i) there is noise pollution problem in Kathmandu, (ii) No Horn Regulation is in place but it has not been strictly followed by the drivers and riders and monitored adequately by concerned authorities, and (iii) the regulation has been effective in reducing the noise level significantly. The average noise level of Kathmandu was recorded as 66.8 dB(A) with the highest noise level in High traffic zones, followed by commercial, low traffic, and residential zones. In 65.2% of the sampled sites, the noise level was beyond the permissible limit of WHO and National Sound Quality Standard of Nepal, 2012. Of the total honking events, 48.1% were against the provision of the No Horn Regulation. After the enforcement of the regulation, noise level was reduced significantly by 2.1 dB(A) in high traffic, low traffic, and residential zones. A comprehensive noise strategy with more emphasis on compliance monitoring and regular noise assessment should be formulated to address environmental noise as a major public health issue.

Temporal and seasonal variations of noise pollution in urban zones: a case study in Pakistan

Noise pollution is widely recognized as an important problem and can negatively affect quality of life. This study aimed to examine the temporal and seasonal variations of noise pollution in urban zones of Peshawar, Pakistan. This city is increasingly becoming congested and traffic-related problems are common. Noise levels were assessed in four different seasons at 20 points around the city, including three different zones: commercial, residential, and silent. All the noise indices including equivalent noise level, day and night time noise level, noise climate, and noise pollution level were calculated for all zones. In winter, the Leq values ranged between 52.5 and 73.3 dBA; while in spring, summer, and autumn, it ranged between 56.2 and 88.3 dBA; 46.9 and 88.6 dBA; and 49.2 and 76.6 dBA, respectively. The level of the noise was observed highest in commercial followed by residential and the silent zones. The levels of the noise were beyond the permissible limits in some zones mentioned in the Pakistan National Environmental Quality Standards (Pak-NEQS' 2010). The seasonal variation in Leq revealed that the noise level in 70% of areas increased from winter to spring, 45% from spring to summer, 35% summer to autumn, 30% autumn to winter, 70% winter to summer, and 40% spring to autumn. Temperature, humidity, and wind speed were the main seasonal factors causing the seasonal variations and traffic was the main source of noise pollution identified in the area.

Characteristics analysis of near-field and far-field aerodynamic noise around high-speed railway bridge

The aerodynamic noise around the high-speed railway bridge is studied by the train-bridge-flow field numerical model and theory analysis. With the background of the Beijing-Shanghai high-speed railway line in China, based on the broadband noise sources method and acoustic analogy theory, both the intensity characteristics of near-field aerodynamic noise sources of the train and the spatial distribution characteristics of far-field aerodynamic noise around the bridge are analyzed. The results show that there is the largest sound source energy on the nose tip of the high-speed train; the fluctuating pressure between air and train surface contributes the most to aerodynamic noise; along the longitudinal direction of the bridge, the aerodynamic noise energy near the junction of train tail and body is the strongest; along the transverse direction of the bridge, the aerodynamic noise energy decreases gradually with the distance from the centerline of the railway; along the vertical direction, the aerodynamic noise energy is the strongest at a location of 1.2 m above the top surface of the rail; the train speed, train type, and the height variation of the bridge pier can affect the distribution of far-field aerodynamic noise.

Evaluation of exposure to road traffic noise: Effects of microphone height and urban configuration

Noise pollution is a major environmental problem due to its impact on human health and implications for other spheres of society. Since road traffic is the main source of noise pollution, the use of measurement methodologies to accurately determine the environmental noise levels to which the façades of buildings in cities are exposed is an important issue. This paper presents an experimental study in urban environments that uses different configurations to evaluate the influence of the position of the microphone and the parking lanes on the levels of road traffic noise to which the population is exposed. In urban settings in which sound waves propagate without obstacles between the lanes of traffic and the receivers, broadband results for the differences between noise levels measured by microphones placed at heights of 4.0 and 1.5 m showed a significant increase with an increase in the distance between the microphone and sound source of between -0.8 and 0.9 dBA over a range from 2 to 8 m. This difference between the two microphones was greater at points where a lane of parked vehicles was located between the road traffic lanes and the receivers were placed near the façades of building. At the same heights, the broadband difference in sound levels ranged from 2.7 to 4.5 dBA. This acoustic shielding effect due to the presence of parked vehicles started to be relevant in the 250 Hz band and increased progressively with frequency. Taking into account these experimental results and the recommendations in the European Noise Directive, it would be important to apply corrections to sound indicators for road traffic noise that are related to the height of the microphone. Making a distinction between urban configurations with and without lines of parked vehicles between the microphone and the road traffic lanes would be advisable.

How does transit-oriented developments (TODs) deviate noise pollution of buildings? A comparative study of TODs and non-TODs

Scholarly debates on the unique features of transit-oriented developments (TODs) have surged over the last decade. Studies have examined their amenities and disamenities; however, lacking is exploring the relationship between TOD sound levels and buildings. Understanding this relationship has implications for communities and the urban form from environmental pollution aspects. This study explores the implications of sound on TOD buildings in the Dallas-Fort Worth metropolitan area by comparing them with non-TODs, specifically the relationship between buildings and street characteristics, and sound, as well as the potential effects of this relationship on TOD residents. Data include sound pressure levels through TOD buildings and streets compared with non-TOD buildings and streets. Using a two-level hierarchical linear model (HLM) help examine such characteristics at both micro and macro levels. The findings show that buildings located within TODs are exposed to higher sound levels with 1.4 dB(A) difference. The study provides insights into the relationship between sound, environmental pollution, building science, and transportation-featured elements of the built environment.

Assessment of noise pollution and associated subjective health complaints and psychological symptoms: analysis through structure equation model

Road traffic noise is affecting the exposed population through its detrimental effects. This study was conducted in urban zones of Peshawar, Khyber Pakhtunkhwa, Pakistan, to analyze causal relationship between noise and subjective health complaints with a special focus on psychological symptoms. A 12-h (LAeq) noise survey conducted at different locations (n = 57) indicated a noise range of 46.3-86.3 dB (A). A questionnaire survey was conducted from local residents (n = 500), students (n = 500), policemen (n = 500), shopkeepers (n = 500), and drivers (n = 500) exposed to road traffic noise and analyzed through structure equation modeling (SEM). Different models were prepared and a modified model obtained the acceptable model fit, i.e., chi-square 0.093, χ²/df 1.286, comparative fit index 0.986, goodness of fit index 0.966, normed fit index 0.943, Tucker-Lewis index 0.977, and root mean square error of approximation 0.034. The modified model gives not only the information about direct but also indirect effects of noise on the exposed population. Adding on, the model clearly indicates that sensitivity to noise has strong relationship with subjective health complaints (headache, exhaustion, and psychological symptoms such as annoyance, difficulty concentrating, ill temper, and anxiety) than profession, age, location, and gender. Duration of exposure to road traffic noise has an important role in increasing the frequency of subjective health issues. The model is important in depicting that sensitivity to noise may produce subjective health complaints (standardized parameter estimates of 0.12 and 0.29) but the mediator has much stronger positive path estimates (0.59). The modified model sought to discover and explicate the underlying mechanism of an observed relationship existing between the selected dependent and an independent variable through the identification of the mediator variables.

An emotional artificial neural network for prediction of vehicular traffic noise

Road traffic is a leading source of environmental noise pollution in large cities, which greatly affects the health and well-being of people. A reliable method for the prediction of road traffic noise is required for monitoring and assessment of traffic noise exposure. This study presents the first application of the Emotional Artificial Neural Network (EANN), as a new generation of neural network method for modeling the road traffic noise in Nicosia, North Cyprus. The efficiency of the EANN model was validated in comparison with the classical feed-forward neural network (FFNN) using two different scenarios with different input combinations. In the first scenario, vehicular classification (the number of cars, medium vehicles, heavy vehicles) and average speed were considered as the models' inputs. In the second scenario, the total traffic and percentage of heavy vehicles were used instead of the classification where the input parameters were total traffic volume, average speed and percentage of heavy vehicles. Application of the EANN model in the prediction of road traffic noise could improve the efficiency of the FFNN, MLR and empirical models at the verification stage up to 14%, 35% and 37%, respectively. Classifying the traffic volume into sub-classes (in scenario 1) before feeding them into the models improved the performance of the EANN and FFNN models at the verification stage by 8% and 12%, respectively. Sensitivity analysis of the input parameters indicated that total traffic volume is the most relevant factor influencing road traffic noise in the study area followed by the number of cars, medium vehicles, heavy vehicles, average speed and percentage of heavy vehicles, respectively.

Evaluation of Building Construction-Induced Noise and Vibration Impact on Residents

Environmental noise and vibration induced by building construction are increasingly prominent in daily life. If the noise and vibration level exceeds the corresponding standard limits stipulated by the country, humans’ normal life, working, or studying efficiency would be interfered. This paper aims to explore how residents respond to noise and vibration mainly induced by the building construction. The noise and vibration measurements, as well as a questionnaire survey, were conducted. Through analysis and comparisons, it is shown that the noise impacts were concentrated in the area near the construction site. For the noise and vibration transmission within the building, the noise levels were amplified in the lower floors and gradually attenuated with floors, and the vibration levels decayed with the floors. The noise impact was much greater than the vibration impact. Building construction was found to be one of the most annoying noise and vibration sources, while the subway operation has little impact on residents according to either subjective or objective evaluation. The ratio of noise and vibration dissatisfaction was less than that of annoyance, which demonstrated that the residents’ psychological capacity was high toward the impact of noise and vibration. The proposed dose-response relationship can apply in a similar community environment. Once the noise levels within the building obtained, the residents’ noise annoyance can then be estimated.