Impact Of Traffic Noise Research Articles

How to get high-rise residential design to respond road traffic noise

Rapid urbanization causes acute contradictions of road traffic noise on residents' health. Although many works have been done in this field, specific investigations of how to get a design of residential area to correspond road traffic noise is still limited, especially in a high population dense area. This paper, therefore, focused on high-rise residential blocks, researching relations between design variables and distribution of road traffic noise. In the study, a typical high population dense city, Shenzhen was employed as study case. Based on noise map simulation, design element, block layout, design of individual buildings was proved important in traffic noise impact. The results discovered that the noise reduction effect is relatively significant when the building setback is within 30 - 40 meters of setback curb. To minimize traffic noise impact, flexible layout of board point perimeter type might play an important role. Lowering building heights with increasing the number of building rows, two-story podiums around high-rise buildings, and the addition of balcony railing plate could result in significant noise reductions. Focusing on design elements, this work developed an overall evaluation to improve acoustic environment of high-rise residentials based on noise map simulation, and provided significant contributions in responding road traffic noise.

Application of Cadna/A software to the prediction of traffic noise on residential envelope sound insulation

The primary issue influencing residential structures' interior sound insulation environments is urban traffic noise. When choosing sound insulation for residential windows and doors, it is essential to consider the influence of road traffic noise. In conjunction with the examples, a three-dimensional simulation prediction model is created early on using Cadna/A software, and it is configured in accordance with the measured data of the road environmental noise to predict the sound pressure level of the outer surface of the residential building's enclosure structure at various locations and floors. This serves as a foundation for choosing the residential building's interior sound-insulated windows and doors as well as for the building's construction. In order to confirm that interior doors and windows are structurally sound-insulated, sound insulation measurements of typical residential sample buildings are made later in the building process.It offers some reference value for using Cadna/A in the assessment and forecasting of traffic noise's impact on the soundproofing of residential building envelopes.

Noise reduction design of new residential buildings along urban roads-taking a residential district in Foshan as an example

Taking a residential district in Foshan along the city road as an example, the impact of urban road traffic noise on it is studied. Firstly, the data is monitored in the noise field, then three-dimensional simulation models of residential buildings and road distribution are established in Cadna/A software, and noise simulation prediction is carried out according to the actual situation and relevant norms and standards. The predicted noise values of the exterior surface of residential buildings are obtained, which has exceeded the permissible interior noise level for residential buildings. By comparing the application effects of noise reduction measures in buildings, the noise reduction design scheme of new residential buildings along urban roads is finally proposed: the sound insulation doors and windows that meet the requirements are adopted. After the completion of the house, the indoor background noise and the sound insulation performance of the doors and windows are measured. The measured results show that the selection of sound insulation doors and windows is suitable and the indoor noise environment meets the design requirements of noise reduction. The results are helpful to provide technical reference for the noise reduction design and renovation of other residential buildings along urban roads.

An investigation into the audio-visual characteristics of restorative spaces using VR

The beneficial effect of nature on stress recovery is a topic of general importance, given that population growth, urbanization and thus noise-induced health impacts are likely to increase in the future. But what makes a recreational space 'restorative'? In this contribution, we present findings from a laboratory experiment using VR environments, on the contributions of different audio-visual characteristics of restorative spaces. Self-reported restorative potential and acoustic quality were assessed in a repeated measures design, varying visual setting (forest, lake, urban built space), soundscape (natural, anthropogenic), and sound pressure level (low, medium, high). First results indicate an additive effect of "naturalness": Restorative potential of spaces with both, natural visuals and natural sounds, was highest, but decreased significantly, when (a) moderate road traffic noise (LAeq ≤ 52 dB) was present, or (b) the visual environment was a non-green urban space. Urban spaces with anthropogenic soundscapes were rated with the lowest restorative potential. While increasing sound pressure levels within an anthropogenic soundscape decreased restorative potential, no such association was found for natural soundscapes. These results simultaneously highlight the beneficial effects of nature and the detrimental impact of road traffic noise on restoration.

Predicting real indoor soundscapes based on auditory and non-auditory factors across different loudness ranges with linear and nonlinear models

Studies on the indoor sound environment have mainly focused on the impact of traffic, neighbor, or ventilation noise on health, annoyance, or sound quality. When conducting such studies in the laboratory, acoustic stimuli are often tailored to the research question, which presumably do not reflect the variation in the acoustic environment at home. Thus, we re-analyzed soundscape data gathered by participants at their homes several times a day. Since the recorded soundscapes differed notably between participants (and their dwellings) in terms of loudness, we investigated if cross-validated linear regression and Random Forest models predicting the soundscape dimensions based on four loudness quartile subsets achieve higher prediction performance compared to models using the full volume range. Our results, which are based on the explanation of the variance in the targets, the correlation between the targets and acoustic and perceptual predictors, and the predictor importance, suggest the use of Random Forest models based on the entire loudness range. In our analysis of predictor importance, Pleasantness was understandably dominated by perceptual measures, whereas Eventfulness was driven through acoustic and psychoacoustic predictors. Interestingly, all models based on quiet soundscapes behaved differently, which provides scope for investigating the underlying causes in future.

Investigation on enhancement of noise reduction of partially open windows and balconies through mock-up test

Application of Acoustic Windows and Acoustic Balconies is a recent trend in Hong Kong to mitigate road traffic noise impact. In severe situations, enhancement is needed for the mitigation measures to provide additional improvement in acoustic performance. The performances of several common enhancements including micro-perforated absorber panels, perforated absorption panels, and balcony sidewalls are investigated through 1:1 mock-up test. The mock-up test aimed to mimic the actual situation, by referencing the spatial relationship between line sources and receivers. International standards are followed in the mock-up test, including ISO 16283-3: 2016 for microphone setting-out and BS EN 1793-3 for normalized traffic noise spectrum. Based on the mock-up test results, the research revealed that the enhancements' performance changes with line source orientation and suggested the optimum usage of enhancements.

Study on territory-wide application of low noise road surface in Hong Kong

Hong Kong is one of the metropolitan cities in the world, with highly concentrated road network system and densely populated developments. At times, it is inevitable to build residential buildings near noisy roads, and traffic noise is one of the environmental problems affecting the locals. The Government strives to pre-empt traffic noise issue through planning new road projects or new residential developments. Concerning traffic noise from existing roads, the Government has implemented noise mitigation measures, for instance, to resurface existing roads with Low Noise Road Surface (LNRS) materials, retrofitting of noise barrier or enclosure, to alleviate traffic noise impact. Moreover, the Government is continuously developing and trialing different LNRS materials such as Polymer Modified Stone Mastic Asphalt (PMSMA6) on roads in Hong Kong, which aims for wider application of LNRS. To explore the feasibility and effectiveness of the wider application of LNRS on local roads, the Government has recently conducted a territory-wide study on the application of LNRS on local roads in Hong Kong. This paper attempts to share the common local road characteristics of applying LNRS material and the latest technical findings, such as the effect on population exposure, of the territory-wide study in Hong Kong.

A framework for the acoustic simulation of passing vehicles using variable length delay lines

The sound produced by vehicles driving on roadways constitutes one of the dominant noise sources in urban areas. The impact of traffic noise on human activities and the related investigation on modeling, assessment, and abatement strategies fueled the research on the simulation of the sound produced by individual passing vehicles. Simulators enable in fact to promote a perceptual assessment of the nature of traffic noise and of the impact of single road agents on the overall soundscape. In this work, we present TrafficSoundSim, an open-source framework for the acoustic simulation of vehicles transiting on a road. We first discuss the generation of the sound signal produced by a vehicle, represented as a combination of road/tire interaction noise and engine noise. We then introduce a propagation model based on the use of variable length delay lines, allowing to simulate acoustic propagation and Doppler effect. The proposed simulator incorporates the effect of air absorption and ground reflection, modeled via complex-valued reflection coefficients dependent on the road surface impedance, as well as a model of the directivity of sound sources representing the passing vehicles. The source signal generation and the propagation stages are decoupled, and all effects are implemented using finite impulse response filters. Moreover, no recorded data is required to run the simulation, making the framework flexible and independent on data availability. Finally, to validate the framework capability to accurately simulate passing vehicles, a comparison between synthetic and recorded pass-by events is presented. The validation shows that sounds generated with the proposed method achieve a good match with recorded events in terms of power spectral density and psychoacoustics metrics as well as a perceptually plausible result.

Soundscape Design in an Urban Natural Park

Urban natural parks represent a remarkable concept that evokes the coexistence of human habitation with a wild environment, and the associated interactions between human and natural territories. In this context, urban noise infringes upon the natural soundscape, leading to various consequences for both realms. This study seeks to characterize the impact of anthropic noise levels on biodiversity in the urban natural Văcărești Park (Bucharest, Romania), utilizing on-site measurements and software simulation techniques. The study seeks to develop a method for evaluating integrative strategies to mitigate the impact of traffic noise on wildlife in an urban wild park, without addressing the specific effects of noise on the perception and communication of individual species. By calibrating field measurements with laboratory results, a more reliable data set will be used to identify areas where the biophonic environment is impacted by anthropogenic noise. Since human-generated noise in an urban natural park predominantly originates from road traffic and industrial sites, managing traffic noise and its propagation pathways could substantially improve the park’s soundscape. Additionally, this study will apply software simulations for noise reduction strategies, such as vegetation planting and earthen embankments, to obtain suitable solutions and propose plausible and effective actions to authorities for improving the biophonic environment. This research could also serve as the basis for long-term monitoring, allowing for the assessment of the evolution and impact of implemented measures over time.

Traffic Projections in Noise Analysis

Traffic volumes are an integral part of any highway traffic noise analysis. The defining procedure for federal regulation for highway transportation noise analysis is 23 CFR 772. Section 23 CFR 772.9 Traffic Noise Prediction (d) states "In predicting noise levels and assessing noise impacts, traffic characteristics that would yield the worst traffic noise impact for the design year shall be used." States have the discretion to determine how to interpret what traffic metrics they use in their federally approved noise analyses. For example, some states use Level of Service (LOS) traffic volumes, while others use peak hour or design hour volume. Some states use an in-depth method to determine loudest hour which incorporates traffic volumes for a twenty four hour period and their corresponding operating speed per hour. This paper will discuss the time and effort associated with each procedure. Case studies will be presented to determine which of these traffic metrics best matches the current traffic counts.

Measurement and prediction of road traffic noise at different floor levels of buildings in a mid-sized Indian city

It is widely accepted that residents of high-rise buildings located beside roads are inevitably exposed to significant levels of noise pollution due to traffic operation. This study aims to unveil crucial insights into the dynamic fluctuations of noise levels within the vertical dimensions of high-rise buildings nestled amidst the bustling streets of mid-sized Indian cities where heterogeneous traffic is under operation. Two cycles of data were collected on all floors for hourly duration on the façade line for two high-rise buildings. Traffic volume, speed, distance of the building from centre of the carriageway and honking were used to develop models for Leq and L10 using Artificial Neural Network (ANN). The R2 values obtained for Leq and L10 were 0.93 and 0.90, respectively indicating the efficacy of the models in predicting noise level at all floors. Results show that the sound level rises to a certain height of the building and then begins to decrease. Floor level 3, 4, 5 and 6 (height approx. 8.4–21 m) had the maximum noise level compared to the other floors, while the 1st and floor level above 10 were quieter floors. Frequency analysis reveals that buildings closer to roadways experience dominant honking noise, particularly at 3.15 kHz, whereas traffic noise prevails at frequencies up to 200 Hz. This work has the novelty of addressing the impact of heterogeneous traffic noise at various floor levels of Varanasi mid-sized city which has narrow carriageway. Such a traffic has prominence of honking which is modelled perhaps for the first time. The outcome of this research has importance in urban planning and formulating legislations.

Assessing Traffic Noise and Its Impact on High-Rise Apartment Buildings Adjacent to an Urban Expressway: A Case Study in Chengdu, China

With rapid urbanization, traffic growth has accelerated in some cities in China. Due to strict urban construction land utilization policies, many high-rise apartment buildings have been constructed adjacent to expressways. To better understand the impact of urban traffic noise on the residents of high residential buildings adjacent to expressways and the differences in noise impacts on different floors, on-site noise monitoring and questionnaires for building residents have been conducted. The characteristics of traffic noise were analyzed based on the measured data, and factors, including time periods and building floors, were considered. According to the results of the questionnaire survey, 56.06% of the male respondents and 54.55% of the female respondents think that the impact of traffic noise on high-rise buildings is “high” or “very high”; 50.53% of the respondents who were in “good” or “very good” condition thought that the traffic noise has a “significant impact” or “very significant impact” on their sleep and daily life. In addition, 25% of respondents living on floors 4–10 and 62.5% of respondents living on floors 11–20 considered the traffic noise to have a “significant impact” or “very significant impact” on their sleep and daily life. The on-site noise monitoring results show that the noise levels (LAeq) outside the windows of the studied buildings remain significantly elevated, with daytime noise on working days ranging from 56 to 70 dB(A), and on weekends ranging from 50 to 65 dB(A). During the four time periods on weekdays from 7 a.m. to 9 a.m., 11 a.m. to 1 p.m., 5 p.m. to 7 p.m., and 10 p.m. to 12 a.m., the average LAeq levels on floors 11–20 are higher than those on floors 4–10 by 4.04 dB(A), 4.92 dB(A), 4.06 dB(A), and 2.67 dB(A), respectively. Similarly, during these time periods on weekends, the levels on floors 11–20 are higher than those on floors 4–10 by 4.96 dB(A), 6.32 dB(A), 5.28 dB(A), and 5.24 dB(A), respectively. This indicates that floors 4–10 of the building experience relatively lower noise levels, while floors 11–20 are subjected to comparatively higher levels of noise disturbance.

Comparative evaluation of soundscapes in human activities spatial contexts of pedestrian spaces adjacent to arterial roads

Pedestrian spaces adjacent to arterial roads are characterized by the dominance of traffic noise alongside various human activities. Research on the impact of traffic noise on the soundscape evaluation of pedestrian spaces has not considered human activities spatial contexts. To address this research gap, the present study constructed auditory environments for pedestrian spaces in the contexts of commuting, residential, and commercial activities. A total of seven auditory environments were subjected to laboratory auditory evaluations, including perceived dominance of sound source, acoustic comfort, and perceived affective quality of the soundscape. The results indicated that in pedestrian spaces with constant traffic noise, the presence of significant human activity sounds led to a decreased perceived dominance of traffic noise and an increased acoustic comfort, despite the higher acoustic energy. Thus, pedestrian spaces with a variety of human activity received better soundscape evaluations. The elements that reflected the human activities spatial contexts, including the types and intensity of human activities, played a crucial role in soundscape evaluations. Better acoustic comfort was reported in pedestrian spaces characterized by low-intensity residential activities and high-intensity commercial activities. Additionally, pedestrian spaces with more intense activities offered an actively engaging soundscape. The findings can provide reference for a more accurate evaluation of the soundscape in pedestrian spaces and guide the soundscape design of pedestrian environments.

Traffic noise transmitted indoors

In numerous countries, traffic noise is widely acknowledged as a highly disturbing form of pollution. Given that individuals spend a substantial portion of their day indoors, the impact of traffic noise perceived indoors is of considerable significance. To establish appropriate sound insulation requirements for buildings, it is essential to correlate subjective annoyance with objective ratings. This paper aims to present the regulations implemented by various countries and present preliminary findings from ongoing studies that involve listening tests using either measured or simulated traffic noise in indoor environments.

Impact of Traffic Noise and Apartment Building Features on the Quality of Life in Matsue City

Traffic noise has a significant impact on the health and quality of life of urban residents. Despite this, there has been limited research on the effects of vehicle-generated noise from roads and parking lots near buildings. This study aimed to examine the impact of traffic and parking noise on residents living in apartments along 11 roads in Matsue City, Japan. To achieve this, the residents' reactions to noise were investigated in relation to the distance of their apartments from main roads and parking lots, as well as the building design. Noise exposures were measured on the road shoulders in front of the properties for 24 hours, and short-term recordings were taken at various reference locations within the buildings. A questionnaire was distributed to 60 households residing in the targeted properties. The results showed that the residents living in apartments along the main roads, which exceeded the noise level limit recommended by the latest World Health Organization (WHO) environmental noise guidelines, expressed annoyance with the traffic noise. The study highlights that the noise issue cannot be solely determined by comparing it to the environmental standards recommended by prefectural standards. The findings suggest the need to review whether the current environmental standards are appropriate for each region.

Prediction and Analysis of Noise Impact and Noise Reduction Scheme Effect for Complex Road Types

In order to improve urban traffic efficiency, complex road types are increasingly common in cities. At the same time, it also increases the impact of noise. As an important noise reduction measure, noise barrier measures are widely used in traffic noise control. The prediction of noise reduction scheme in advance is conducive to the scientific and reasonable setting of noise barrier measures. In this paper, based on the impact of traffic noise from elevated roads on a residential building, the noise prediction software is used to simulate the scene, and the model is calibrated with the field measured data, and the noise contribution of elevated road and ground road to sensitive targets is quantitatively analyzed. On this basis, the noise reduction effects of different types of noise barrier measures, such as vertical, bending, semi-closed and fully-closed, on sensitive targets are analyzed. The effect of different additional length on noise reduction is further analyzed. The simulation analysis also focuses on the key buildings and floors that are seriously affected by road noise, providing sufficient technical support for the implementation of the subsequent overall noise reduction project.

Signal setting design to reduce noise emissions in a connected environment

To meet the zero-pollution target on noise by 2030, it is necessary to develop mobility management policies that directly act on noise exposure. This paper proposes traffic signal optimisation in an environment with fully connected vehicles (CVs), combining noise pollution minimisation with total travel time minimisation to improve traffic flow. Traffic signal optimisation was tested on a network with signalised interacting junctions, comparing different approaches and scenarios based on short-range communication between the infrastructure and CVs approaching the junctions. The results show that the proposed traffic control method may be adopted to effectively reduce the impact of traffic noise and improve traffic performance.

Contributions of residential traffic noise to depression and mental wellbeing in Hong Kong: A prospective cohort study

Prior studies on the association between traffic noise and mental health have been mostly conducted in settings with lower population densities. However, evidence is lacking in high population-density settings where traffic noise is more pervasive and varies by topography and the vertical elevation of the residential unit. This study aimed to assess the mental health impact of residential traffic noise in one of the world's most urbanised populations. Data were analysed from 13,401 participants aged ≥15 years in a prospective cohort in Hong Kong from 2009 to 2014. Residential traffic noise level was estimated using 3D-geocoding and validated models that accounted for sound propagation in a highly vertical landscape. The 24-h day-night exposure to traffic noise, denoted as Ldn, was estimated with a 10-dB(A) penalty for night hours. Probable depression and mental wellbeing were assessed using the Patient Health Questionnaire-9 and the Short Form Health Questionnaire SF-12v2, respectively. Mixed effect regressions with random intercepts were used to examine the association between traffic noise and mental health outcomes. Residential road traffic noise (for each increment of 10 A-weighted decibels [dB(A)] 24-h average exposure) was associated with probable depression (odds ratio (OR) = 1.17, 95% CI: 1.05, 1.31), and poorer mental wellbeing (mean difference = −0.19, 95% CI: 0.31, −0.06), adjusting for sociodemographics, smoking, body mass index, self-reported health, proximity to green space, and neighbourhood characteristics (average household income, population density, and Gini coefficient). The results were robust to further adjustment for air pollution. In stratified analyses, residential traffic noise was associated with probable depression and poorer mental wellbeing among students and individuals aged 15–34 years. Residential traffic noise was associated with probable depression and poorer mental wellbeing in a highly urbanised setting. As traffic noise is increasing in urban settings, the public health impact of noise pollution could be substantial.

Analysis of the impact of low-frequency traffic noise in two South American cities

Traffic noise is one of the most important sources of annoyance in South American cities. The obsolescence of vehicles and the lack of controls are two of the main causes of this noisy traffic. Since the legislation considers it as a typical source of urban noise, the metric to analyze traffic noise is the A-weighted dB (so-called dBA); therefore, it is not easy to analyze its real impact on human health because low-frequency sound levels are strongly reduced by A-weighting. This article presents the results of a field study carried out in Lima (Peru) and Montevideo (Uruguay) to analyze the impact of traffic noise focused the lowest frequencies, in the range defined by ISO (1/3 octave bands between 16 and 200 Hz), and the WHO recommendation using the whole audible frequencies. The data for Lima were taken in places where a specific acoustic EIS has been required, while the Montevideo´s one were for its noise map. The spectra were processed looking for a representative low-frequency traffic noise metric, so the values of (C–A) obtained byWHO recommendation and ISO recommendation are compared. The expected impact on human health is much more worrisome when low-frequencyrange are explicitly considered.

An assessment of the effectiveness of acoustic treatments for balconies and open spaces as required by Queensland State Assessment and Referral Agency

This study examines the effectiveness of acoustic treatments required to fulfill “Queensland State Assessment and Referral Agency (SARA)” conditions for balconies or private open spaces in apartment units above the ground floor. SARA SDAP State Code 1 Performance and Acceptable Outcome PO42 mandates developers to use a combination of continuous, solid, gap-free structures or balustrades and highly acoustically absorbent material treatments for such locations. The study explores the relevance of SARA conditions to balconies and highlights the absence of specific statistical noise level criteria for upper-floor private open spaces affected by traffic noise from state-controlled roads in Queensland. Furthermore, the Code requires these measures for balconies “adjacent” to state-controlled roads, which DTMR defined to be within 100 m of a state transport corridor and/or infrastructure. To investigate these aspects, computational noise modeling was undertaken to predict and assess the impact of road traffic noise on balconies, considering factors such as diffraction, reflection, and direct noise propagation paths. The study also analyzes the potential benefits of acoustic treatments, which were found to be dependent on sight angles to and distances from state-controlled road. In certain cases, minimal acoustic benefits are observed. It is recommended that there is a shift from prescriptive acoustic requirements to performance-based and building-specific requirements within the SARA framework.