道路交通噪声预测的研究进展

为评价道路交通噪声影响情况,以美国联邦公路管理局(FHWA)噪声预测模型为主,各国相继开发了基于当地实际情况的道路交通噪声预测模型,中国也以导则和规范等形式相继发布了各种交通噪声预测模型。中国进行噪声环境影响评价中,用得较多的主要有《环境影响评价技术导则声环境》(HJ 2.4—2009)、《公路建设项目环境影响评价规范》(JTG B03—2006)推荐的噪声预测模型,此外也有部分评价工作采用了德国的Cadna A软件。通过对比分析,HJ 2.4—2009的衰减及修正因素在综合考虑FH-WA噪声预测模型及JTG B03—2006基础上更加全面,而JTG B03—2006和Cadna A软件在源强和车速确定方面则均较成熟。有必要根据区域道路特点,选择适合特征区域的道路交通噪声预测模型,并结合实际情况对模型参数进行合理修正,最终形成一些可供区域参考的统一的模型修正参数,积极推动中国的声环境评价工作的发展。     

室内箱式变压器结构声污染及对策

通过对置于住宅楼底层室内箱式变压器引起的结构声污染进行调查实测，在对箱式变压器结构声传播进行声学分析基础上，提出了切实可行的防治对策，经实际工程应用验证，效果较好。对机房正上方住房主卧内降噪量为5.0dB，室内夜间噪声降为30.2dB，各层住户夜间烦恼度普遍从非常烦恼或烦恼降为有点烦恼和不大烦恼。这从噪声污染控制的角度证明了变配电房置于住宅楼等噪声敏感建筑物室内底层甚至更高楼层在技术上是可行性的。同时也为杭州市正在试点推广的箱式变压器置于噪声敏感建筑物底层提供了实践依据。     

基于GIS城市道路交通噪声环境管理系统的构架与实现

详细介绍了基于GIS技术开发城市道路交通噪声环境管理系统的构架与实现.该系统的开发工作主要包括:噪声数据库设计、噪声数据管理、交通噪声的模拟和交通噪声影响统计.系统采用了数据库技术、GIS技术和交通噪声预测模型,综合考虑实际情况,对城市噪声环境进行管理和模拟.从实例结果分析可见,模拟结果能达到实际使用的要求.该系统能为城市规划、城市环境评价提供信息和技术支持.     

Spatio-temporal covariation of urban particle number concentration and ambient noise

Mobile measurements of ambient noise and particle number concentrations were carried out within an urban residential area in Essen, Germany, during summer 2008. A busy major road with a traffic intensity of about 44,000 vehicles per day was situated within the study area. The spatio-temporal distribution of noise and particles was closely coupled to road traffic on the major road. Total particle number concentrations in proximity to the main road were on average between 25,000 cm^?3 and 35,000 cm^?3 while sound levels reached 70–78 dB(A). These estimates were more than double-fold (factor 2.4) in comparison to the urban residential background. At a 50 m distance off the road particle number concentrations were decaying to about 50% of the initial value. The measurements were characterised by close spatial correlation between total particle number concentration and ambient noise with correlation coefficients of up to r = 0.74. However, during one measurement day coupling between both quantities was weak due to higher turbulent mixing within the canopy layer and a change in ambient wind directions. Enhanced dilution of particle emission from road traffic by turbulent mixing and ‘decoupling’ from the influence of road traffic are believed to be responsible.     

Impacts of pavement types on in-vehicle noise and human health

Noise is a major source of pollution that can affect the human physiology and living environment. According to the World Health Organization (WHO), an exposure for longer than 24 hours to noise levels above 70 dB(A) may damage human hearing sensitivity, induce adverse health effects, and cause anxiety to residents nearby roadways. Pavement type with different roughness is one of the associated sources that may contribute to in-vehicle noise. Most previous studies have focused on the impact of pavement type on the surrounding acoustic environment of roadways, and given little attention to in-vehicle noise levels. This paper explores the impacts of different pavement types on in-vehicle noise levels and the associated adverse health effects. An old concrete pavement and a pavement with a thin asphalt overlay were chosen as the test beds. The in-vehicle noise caused by the asphalt and concrete pavements were measured, as well as the drivers’ corresponding heart rates and reported riding comfort. Results show that the overall in-vehicle sound levels are higher than 70 dB(A) even at midnight. The newly overlaid asphalt pavement reduced in-vehicle noise at a driving speed of 96.5 km/hr by approximately 6 dB(A). Further, on the concrete pavement with higher roughness, driver heart rates were significantly higher than on the asphalt pavement. Drivers reported feeling more comfortable when driving on asphalt than on concrete pavement. Further tests on more drivers with different demographic characteristics, along highways with complicated configurations, and an examination of more factors contributing to in-vehicle noise are recommended, in addition to measuring additional physical symptoms of both drivers and passengers.Implications: While there have been many previous noise-related studies, few have addressed in-vehicle noise. Most studies have focused on the noise that residents have complained about, such as neighborhood traffic noise. As yet, there have been no complaints by drivers that their own in-vehicle noise is too loud. Nevertheless, it is a fact that in-vehicle noise can also result in adverse health effects if it exceeds 85 dB(A). Results of this study show that in-vehicle noise was strongly associated with pavement type and roughness; also, driver heart rate patterns presented statistically significant differences on different types of pavement with different roughness.     

Assessing the perceived impact of exploration and production of hydrocarbons on households perspective of environmental regulation in Ghana

This paper seeks to critically study the perceived impacts of the exploration of hydrocarbons in selected coastal communities in the Western region, the oil and gas industry benefits to local communities, and to determine whether hydrocarbon development is a means for sustainable development. The study uses both quantitative and qualitative approaches using a questionnaire survey, key informant interview, and focus group discussion tools to understand the impact of oil and gas exploration and production in selected affected communities along the coast of Ghana. The activities of oil production and exploration impact negatively on communities; it also leads to a sharp increase in food prices thereby increasing their costs of living. The activity has also caused a decline in fish catch levels which happens to be the main economic activity as a result of exclusion zones created by oil companies which limited the extent fishermen can go fishing. In terms of infrastructure, the three communities are lacking, 77% of respondents from Princess Town hold the view that there is no motorable road linking their community in the next town and 60% from Aketakyi also hold the same view. Infrastructure such as roads, schools, water provision, and clinics are woefully provided in these communities.

     

快速高架复合道路近场交通噪声垂向分布

采用Cadna/A环境噪声模拟软件建立了高架复合道路的基本模型,根据6种基本模拟情况进行了声场模拟,并把模拟结果与实测结果进行对比分析。结果表明,高架道路结构本身对地面道路、高架道路分别形成的声场有明显的遮挡作用,但对高架复合道路所形成的声场遮挡作用不明显;对于高架复合道路垂向声场,在低层段地面道路的影响大于高架道路,而在高层段高架道路的影响起决定作用;高架复合道路较地面道路的垂向声场最大值增加2.5 dB(A),位置上移6m;在高架道路上设置声屏障有一定降噪效果,但在高架复合道路的上层设置声屏障降噪效果不理想。     

Traffic and Meteorological Impacts on Near-Road Air Quality: Summary of Methods and Trends from the Raleigh Near-Road Study

Abstract

A growing number of epidemiological studies conducted worldwide suggest an increase in the occurrence of adverse health effects in populations living, working, or going to school near major roadways. A study was designed to assess traffic emissions impacts on air quality and particle toxicity near a heavily traveled highway. In an attempt to describe the complex mixture of pollutants and atmospheric transport mechanisms affecting pollutant dispersion in this near-highway environment, several real-time and time-integrated sampling devices measured air quality concentrations at multiple distances and heights from the road. Pollutants analyzed included U.S. Environmental Protection Agency (EPA)-regulated gases, particulate matter (coarse, fine, and ultrafine), and air toxics. Pollutant measurements were synchronized with real-time traffic and meteorological monitoring devices to provide continuous and integrated assessments of the variation of near-road air pollutant concentrations and particle toxicity with changing traffic and environmental conditions, as well as distance from the road. Measurement results demonstrated the temporal and spatial impact of traffic emissions on near-road air quality. The distribution of mobile source emitted gas and particulate pollutants under all wind and traffic conditions indicated a higher proportion of elevated concentrations near the road, suggesting elevated exposures for populations spending significant amounts of time in this microenvironment. Diurnal variations in pollutant concentrations also demonstrated the impact of traffic activity and meteorology on near-road air quality. Time-resolved measurements of multiple pollutants demonstrated that traffic emissions produced a complex mixture of criteria and air toxic pollutants in this microenvironment. These results provide a foundation for future assessments of these data to identify the relationship of traffic activity and meteorology on air quality concentrations and population exposures.     

Effect of Plantings on Radiation of Highway Noise

The body of information presented in this paper is directed to those individuals concerned with the location of highways relative to either existing or planned residential communities. The paper treats in depth the expected attenuation of automobile and particularly diesel tractor-trailer generated hoise by the interposition of extensive and dense planting of trees and shrubs between the highway and the community. The results of research, by the author and others cited in the paper, gives clear indication that a belt of dense man-made growth of tall trees and underbrush can give as much as 5 to 8 dB truck/car noise reduction per 100 ft of planting depth. Natural growth of deep forests were measured to give from 3 to 5 dB attenuation per 100 ft of planting depth. Planting depth of at least 100 ft is required to give reliable results, with tree heights of 40-50 ft desirable and densities of 50-70 ft visibility needed for good effect.

The paper provides considerable experimental verification by an analysis of the current literature. The types of noise sources in cars and trucks are briefly treated as are community reactions to noise from such sources. The dBA is used as the accepted measure for characterizing truck and automobile noise. Both spherical and cylindrical radiation of sound are discussed for low density and high density traffic, respectively.

The paper concludes with an example of attenuation of a typical truck noise by spherical and cylindrical radiation for low- and high-density traffic and a 200-ft deep planting of dense, mature forest. It is concluded that a mature belt of either coniferous or deciduous forest with underbrush can produce barely acceptable noise levels in the community which is separated by such a noise barrier from a heavily traveled highway.     

Prediction of Traffic Noise: A Screening Technique

Abstract

Traffic noise is ubiquitous in many communities and is an important environmental concern, especially for persons located near major roadways. Several different methods are available to estimate noise levels resulting from roadway traffic. These include computational, graphical, and computer modeling techniques.

The prediction methodology presented here is a simplified technique that can be used for estimating noise resulting from traffic and for screening traffic noise impacts. This Traffic Noise Screening (TNS) approach consists of a series of traffic noise level prediction graphs developed for different roadway configurations. The graphs are based on the results from using the Federal Highway Administration (FHWA) STAMINA2.0 computerized noise prediction model for various scenarios. Data inputs to the TNS approach include roadway geometries, traffic volumes, vehicle travel speed, and centerline distance to the receptors.

The TNS graphs allow easy estimation of traffic noise levels for use in predicting traffic-related noise impacts. This TNS approach is not intended as a substitute for detailed modeling, such as with STAMINA2.0, but as a screening tool to aid in determining when detailed modeling may be necessary. If screening results indicate that noise estimates are significant, or if the scenario is rather complex, then additional, more detailed modeling can be performed.     

Methods of investigating urban wind fields—physical models

For evaluation of environmental problems in urban areas, models are needed. Physical models and mathematical models are the tools of the trade. Both types of models have advantages and limitations. The emphasis here is on boundary layer wind tunnels, which are well suited for the study of many urban climate situations. The boundary layer flow along the floor of a meteorological wind tunnel is a real flow which approximately represents a scaled down version of the atmospheric boundary layer under conditions of neutral stratification. Therefore, important practical problems involving urban atmospheric conditions can be studied in such wind tunnels by means of geometrically similar models of the urban area. Such problems involve wind forces on structures, pedestrian comfort, and diffusion processes from point sources, such as chimneys, tunnel exhausts and gaseous spills, or from line sources, such as traffic lines. The investigation of these processes in a wind tunnel must be seen, however, as one link only in a chain of actions.     

Lagrangian Dispersion Modeling of Vehicular Emissions from a Highway in Complex Terrain

Abstract

Transit traffic through the Austrian Alps is of major concern in government policy. Pollutant burdens resulting from such traffic are discussed widely in Austrian politics and have already led to measures to restrict traffic on transit routes. In the course of an environmental assessment study, comprehensive measurements were performed. These included air quality observations using passive samplers, a differential optical absorption spectroscopy system, a mobile and a fixed air quality monitoring station, and meteorological observations. As was evident from several previous studies, dispersion modeling in such areas of complex terrain and, moreover, with frequent calm wind conditions, is difficult to handle. Further, in the case presented here, different pollutant sources had to be treated simultaneously (e.g., road networks, exhaust chimneys from road tunnels, and road tunnel portals). No appropriate system for modeling all these factors has so far appeared in the literature. A prognostic wind field model coupled with a Lagrangian dispersion model is thus presented here and is designed to treat all these factors. A comparison of the modeling system with results from passive samplers and from a fixed air quality monitoring station proved the ability of the model to provide reasonable figures for concentration distributions along the A10.     

A Quantitative Approach to the Traffic Air Quality Problem: The Traffic Air Quality Index

Abstract

The Traffic Air Quality (TAQ) model is a simple tool to estimate traffic fine particulate emissions on roadways (g/km) and can be used for both real-time analysis and for localized conformity analysis (“hot-spot” analysis for nonattainment areas) as defined by 40 CFR 93.123. This paper is a follow-up to a study published earlier regarding the development of the TAQ model. This paper shows how local air quality levels can be a factor in traffic management in nonattainment areas. Similar to the industrial source quotas measured in tons per year, it is proposed that road segments are to be assigned emission quotas (or TAQ indices) measured in pollutant mass emitted per road length (g/km) above which traffic-measures have to be taken to reduce the fine-particulates emissions on such road links. The TAQ model as well as traffic-rerouting measures along with the Intelligent Transportation System (ITS) protocols can be used to have a real-time control of the traffic conditions along expressways to maintain the fine-particulates emissions below the quota assigned per road link and consequently improving the over all local air quality in nonattainment areas.     

高架道路声屏障的降噪效果

详细介绍了德国RLS 90道路交通噪声预测模型,运用RLS 90模型对具有典型道路参数的高架道路试验段在不同距离、不同高度下进行了辐射噪声和声屏障降噪效果特性的预测计算,并进行了实际测量.结果表明,高架道路对低于其路面高度的近距离区域有显著的噪声遮蔽作用,对于高架道路,声屏障对路面高度附近的区域降噪效果最佳,4 m高声屏障的最大降噪效果达10 dB.结果还表明,采用RLS 90模型得到的高架道路噪声级和声屏障降噪效果计算值和实测数据吻合良好.     

道路交通噪声预测模式预测结果的比较

为了分析实际环境影响评价中常用的各种公路交通噪声预测模型预测结果之间存在的差异,并验证各预测方式与实测值之间的相符性,通过对选取的高速公路和市政快速公路采用各种预测模型计算比较,并用实际监测值对各模型预测结果进行验证,结果发现,不同的预测方式会造成预测结果之间昼间4～9 dB、夜间5～10 dB的差异,采用2006版规范计算车速和单车噪声源强,距离衰减考虑车流量大小的预测方式得到的预测结果与实测值最为接近。     

Characteristics of colloids and their affinity for heavy metals in road runoff with different traffic in Beijing,China

The characteristics of colloids in urban road runoff with different traffic in Beijing, China, such as concentration, particle size, chemical property, and affinity for heavy metals were determined. The concentration of colloids was high, and an evident first flush effect was found in the runoff of road with heavy traffic. A large portion of colloids were distributed in the range of 1–10 μm. Traffic activity, rainfall intensity, and time of sample collection would not change the size distribution of colloids in the road runoff. The chemical property of colloids in the road runoff would be influenced by the soil erosion nearby green space, causing the content of organic colloids was high. The correlation coefficient between the concentration of colloids in colloidal fractions and the concentration of heavy metals (Cu, Zn, Cd, Pb, Fe, and Mn) in the road runoff with different traffic decreased with the same sequence from 0.02–0.2 μm, 0.2–0.45 μm, 0.45–1 μm, to 1–10 μm, suggesting that the heavy metals had stronger affinity for the colloids with small size. The concentration of Cu, Pb, and Zn exhibited significant correlations with the concentration of organic colloids in the road runoff. More aggregated spherical particles were found in the TEM image of the road runoff with heavy traffic. Zeta potentials and RMV data showed that the colloids with smaller size and the colloids in the road runoff with lighter traffic were much more stable.

     

Model calculation of environmentally friendly traffic flows in a rapidly growing urban centre in India

The paper highlights the application of an integrated decision support system for calculation of environmental friendly traffic flows in urban networks under different management strategies. Each proposed alternative is evaluated using a GIS and GPS environment that may, on a local basis, affect the environmental burden and contribute to pollution load in the region. For each link of the network an environmental capacity is calculated, taking into consideration the hydrodynamic theory based traffic flow dependent on the length of the road network and the average traffic volume and speed. The studied management options include: modifying the existing road network; road widening activities; bus bay relocation; construction of RUB/ROBs; rescheduling the work activities; parking management. The integrated transportation decision support system offers entirely new way of using the GIS, GPS and field survey data for model calculation of pollution load from road traffic to devise environmentally friendly traffic flows.     

Outdoor-Indoor Levels of Six Air Pollutants

Comparisons were made of the levels of six air pollutants—total oxidant, per-oxyacetyl nitrate (PAN), nitric oxide, nitrogen dioxide, carbon monoxide, and particulate matter—outside and inside 11 buildings in the South Coast Basin of California during summer and fall.

Total oxidant levels inside depend upon how much outside air is being brought in and the residence time in the structure. With rapid intake and circulation, levels inside may be two-thirds those outside. With little intake and slow circulation, amounts inside decay to near zero. PAN is more persistent in buildings because it is more stable than ozone but also decays to low levels over an extended period. Oxides of nitrogen and CO are much more stable than oxidant or PAN and when carried into buildings remain until diluted or exhausted.

Particulate matter levels indoors depend largely upon velocity of air movement. Indoor areas where foot traffic was light or which had low ventilation rates had reduced amounts of particulate. Electrostatic precipitators were much more effective than coarse primary filters used in many buildings for removing particulate matter.     

Traffic and meteorological impacts on near-road air quality: summary of methods and trends from the Raleigh Near-Road Study

A growing number of epidemiological studies conducted worldwide suggest an increase in the occurrence of adverse health effects in populations living, working, or going to school near major roadways. A study was designed to assess traffic emissions impacts on air quality and particle toxicity near a heavily traveled highway. In an attempt to describe the complex mixture of pollutants and atmospheric transport mechanisms affecting pollutant dispersion in this near-highway environment, several real-time and time-integrated sampling devices measured air quality concentrations at multiple distances and heights from the road. Pollutants analyzed included U.S. Environmental Protection Agency (EPA)-regulated gases, particulate matter (coarse, fine, and ultrafine), and air toxics. Pollutant measurements were synchronized with real-time traffic and meteorological monitoring devices to provide continuous and integrated assessments of the variation of near-road air pollutant concentrations and particle toxicity with changing traffic and environmental conditions, as well as distance from the road. Measurement results demonstrated the temporal and spatial impact of traffic emissions on near-road air quality. The distribution of mobile source emitted gas and particulate pollutants under all wind and traffic conditions indicated a higher proportion of elevated concentrations near the road, suggesting elevated exposures for populations spending significant amounts of time in this microenvironment. Diurnal variations in pollutant concentrations also demonstrated the impact of traffic activity and meteorology on near-road air quality. Time-resolved measurements of multiple pollutants demonstrated that traffic emissions produced a complex mixture of criteria and air toxic pollutants in this microenvironment. These results provide a foundation for future assessments of these data to identify the relationship of traffic activity and meteorology on air quality concentrations and population exposures.     

Modeling vehicle interior noise exposure dose on freeways: Considering weaving segment designs and engine operation

Vehicle interior noise functions at the dominant frequencies of 500 Hz below and around 800 Hz, which fall into the bands that may impair hearing. Recent studies demonstrated that freeway commuters are chronically exposed to vehicle interior noise, bearing the risk of hearing impairment. The interior noise evaluation process is mostly conducted in a laboratory environment. The test results and the developed noise models may underestimate or ignore the noise effects from dynamic traffic and road conditions and configuration. However, the interior noise is highly associated with vehicle maneuvering. The vehicle maneuvering on a freeway weaving segment is more complex because of its nature of conflicting areas. This research is intended to explore the risk of the interior noise exposure on freeway weaving segments for freeway commuters and to improve the interior noise estimation by constructing a decision tree learning–based noise exposure dose (NED) model, considering weaving segment designs and engine operation. On-road driving tests were conducted on 12 subjects on State Highway 288 in Houston, Texas. On-board Diagnosis (OBD) II, a smartphone-based roughness app, and a digital sound meter were used to collect vehicle maneuvering and engine information, International Roughness Index, and interior noise levels, respectively. Eleven variables were obtainable from the driving tests, including the length and type of a weaving segment, serving as predictors. The importance of the predictors was estimated by their out-of-bag–permuted predictor delta errors. The hazardous exposure level of the interior noise on weaving segments was quantified to hazard quotient, NED, and daily noise exposure level, respectively. Results showed that the risk of hearing impairment on freeway is acceptable; the interior noise level is the most sensitive to the pavement roughness and is subject to freeway configuration and traffic conditions. The constructed NED model shows high predictive power (R = 0.93, normalized root-mean-square error [NRMSE] < 6.7%).

Implications: Vehicle interior noise is usually ignored in the public, and its modeling and evaluation are generally conducted in a laboratory environment, regardless of the interior noise effects from dynamic traffic, road conditions, and road configuration. This study quantified the interior exposure dose on freeway weaving segments, which provides freeway commuters with a sense of interior noise exposure risk. In addition, a bagged decision tree–based interior noise exposure dose model was constructed, considering vehicle maneuvering, vehicle engine operational information, pavement roughness, and weaving segment configuration. The constructed model could significantly improve the interior noise estimation for road engineers and vehicle manufactures.