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.     

废旧混凝土用作水泥稳定基层的实验研究

随着城市建设的发展,城市道路改建时产生的大量的废弃混凝土块的有效利用成了一个亟待解决的问题。结合宜昌市东山大道改建项目,将废弃的混凝土面板加工形成再生集料用作水泥稳定碎石基层,达到节约资源和保护环境的目的。实验分析了再生集料的颗粒级配、压碎值、针片状颗粒含量、表观密度和吸水率等工程性质指标,同时对水泥稳定再生碎石的级配、最佳水泥掺量进行了设计,并对水泥稳定再生碎石的无侧限抗压强度指标进行了研究。研究表明,废旧混凝土经加工形成的再生集料具有良好的路用性能,其颗粒级配、压碎值以及主要指标均达到了路面基层材料的要求;掺3%、5%和7%水泥稳定再生集料7 d浸水抗压强度均达到路面基层的要求,水泥稳定再生集料用作路面基层是可行的;掺3%水泥稳定的再生集料可以用在公路的底基层,掺5%及7%水泥稳定的再生集料可以分别用作路面下基层和上基层。     

Experimental studies of the dilution of vehicle exhaust pollutants by environment-protecting pervious pavement

This study determines whether environment-protecting pervious pavement can dilute pollutants immediately after emissions from vehicle. The turbulence-driven dry-deposition process is too slow to be considered in this aspect. The pavement used is the JW pavement (according to its inventors name), a high-load-bearing water-permeable pavement with patents in over 100 countries, which has already been used for more than 8 years in Taiwan and is well suited to replacing conventional road pavement, making the potential implementation of the study results feasible. The design of this study included two sets of experiments. Variation of the air pollutant concentrations within a fenced area over the JW pavement with one vehicle discharging emissions into was monitored and compared with results over a non-JW pavement. The ambient wind speed was low during the first experiment, and the results obtained were highly credible. It was found that the JW pavement diluted vehicle pollutant emissions near the ground surface by 40%-87% within 5 min of emission; whereas the data at 2 m height suggested that about 58%-97% of pollutants were trapped underneath the pavement 20 min after emission. Those quantitative estimations may be off by +/- 10%, if errors in emissions and measurements were considered. SO2 and CO2 underwent the most significant reduction. Very likely, pollutants were forced to move underneath due to the special design of the pavement. During the second experiment, ambient wind speeds were high and the results obtained had less credibility, but they did not disprove the pollutant dilution capacity of the JW pavement. In order to track the fate of pollutants, parts of the pavement were removed to reveal a micro version of wetland underneath, which could possibly hold the responsibility of absorbing and decomposing pollutants to forms harmless to the environment and human health.     

Evaluating exposure of pedestrians to airborne contaminants associated with non-potable water use for pavement cleaning

Climate change and increasing demography press local authorities to look after affordable water resources and replacement of drinking water for city necessities like street and pavement cleaning by more available raw water. Though, the substitution of drinking by non-drinking resources demands the evaluation of sanitary hazards. This article aims therefore to evaluate the contribution of cleaning water to the overall exposure of city dwellers in case of wet pavement cleaning using crossed physical, chemical and biological approaches. The result of tracer experiments with fluorescein show that liquid water content of the cleaning aerosol produced is about 0.24 g m^?3, rending possible a fast estimation of exposure levels. In situ analysis of the aerosol particles indicates a significant increase in particle number concentration and particle diameter, though without change in particle composition. The conventional bacterial analysis using total coliforms as tracer suggests that an important part of the contamination is issued from the pavement. The qPCR results show a more than 20-fold increase of background genome concentration for Escherichia coli and 10-fold increase for Enterococcus but a negligible contribution of the cleaning water. The fluorescence analysis of the cleaning aerosol confirms the above findings identifying pavement surface as the major contributor to aerosol organic load. The physical, chemical and microbiological approaches used make it possible to describe accurately the cleaning bioaerosol and to identify the existence of significantly higher levels of all parameters studied during the wet pavement cleaning. Though, the low level of contamination and the very short time of passage of pedestrian in the zone do not suggest a significant risk for the city dwellers. As the cleaning workers remain much longer in the impacted area, more attention should be paid to their chronic exposure.     

Identifying influencing factors on paved roads silt loading

The factors that influence the increase or decrease of silt loadings on paved roadways have not been fully quantitatively investigated. They were identified in this study based on the quarterly silt loading sampling data collected from 20 sites by the Clark County Department of Air Quality and Environmental Management in Southern Nevada for the period from 2000 to 2003. The silt loading and associated data collected over these years at one sampling site may inherently possess site-specific characteristics that can be better incorporated by using panel data models. The factors that are identified as significant are the presence of curbs and gutters, shoulder type, pavement conditions, and the presence of construction activities in the vicinity of roadways. The presence of curbs and gutters, stabilized shoulders, and good pavement conditions would result in decreased silt loadings. Conversely, the presence of construction activities within the immediate vicinity of sampled areas would result in increases of silt loadings on the roadway surfaces. Based on the analysis of the results, it was recommended that constructing curbs, gutters and stabilized shoulders, preventing or reducing construction track-out from construction activity, and improving pavement conditions be the preferred control measures to reduce silt loading on paved roadways.     

Identifying Influencing Factors on Paved Roads Silt Loading

Abstract

The factors that influence the increase or decrease of silt loadings on paved roadways have not been fully quantitatively investigated. They were identified in this study based on the quarterly silt loading sampling data collected from 20 sites by the Clark County Department of Air Quality and Environmental Management in Southern Nevada for the period from 2000 to 2003. The silt loading and associated data collected over these years at one sampling site may inherently possess site-specific characteristics that can be better incorporated by using panel data models. The factors that are identified as significant are the presence of curbs and gutters, shoulder type, pavement conditions, and the presence of construction activities in the vicinity of roadways. The presence of curbs and gutters, stabilized shoulders, and good pavement conditions would result in decreased silt loadings. Conversely, the presence of construction activities within the immediate vicinity of sampled areas would result in increases of silt loadings on the roadway surfaces. Based on the analysis of the results, it was recommended that constructing curbs, gutters and stabilized shoulders, preventing or reducing construction track-out from construction activity, and improving pavement conditions be the preferred control measures to reduce silt loading on paved roadways.     

Assessing the health risk of reuse of bottom ash in road paving

Although the reuse of bottom ash has been favored gradually, reflected on regulations and researches, the associated risk is still an issue of great concern. This study quantified the health risks from multimedia transport and multi-pathway exposure to the concerned chemicals as a result of reusing bottom ash in road paving with consideration of various application scenarios. In particular, the using duration of the pavement was taken into consideration because movement of chemicals in the soils and groundwater would affect the subsequent exposure and risk. By using soil and groundwater transport modeling linked to food chain exposure assessment and incorporating the Monte Carlo method, the study identified Cr as the crucial toxicant and ingestion of drinking water and vegetables as the key exposure pathways. Furthermore, control of the using duration of road pavement is an essential factor of management and regulations to minimize the leaching of the hazardous constituents into the groundwater and subsequent contamination of food chain.     

Factors influencing PM10 emissions from road pavement wear

Accelerated pavement wear is one of the major environmental disadvantages of studded tyres in northern regions and results in increased levels of PM₁₀. Measurements of PM₁₀ in a road simulator hall have been used to study the influence of pavement properties, tyre type and vehicle speed on pavement wear. The test set-up included three different pavements (one granite and two quartzite with different aggregate sizes), three different tyre types (studded, non-studded, and summer tyres) and different speeds (30–70 km h^?1). The results show that the granite pavement was more prone to PM₁₀ production compared to the quartzite pavements. Studded winter tyres yield tens of times higher PM₁₀ concentrations compared to non-studded winter tyres. Wear from summer tyres was negligible in comparison. It was also shown that wear is strongly dependent on speed; every 10 km h^?1 increase yielded an increase of the PM₁₀ concentration of 680 μg m^?3 in one of the simulator experiments.     

粉煤灰资源化特性及路面工程应用技术研究

对粉煤灰的各项技术参数进行了试验研究,揭示出粉煤灰的不同成分和形貌对其资源化特性的影响规律,初步完成了消除不利于粉煤灰资源化的有害成分炭的优化实验工作,进行了脱炭粉煤灰混凝土配合比等试验研究,并在路面修复工程中予以应有,结果表明,经脱炭处理的粉煤灰应用于混凝土工程可以明显改善混凝土的工作性能,实际道路运营和技术性能符合路面工程的要求,具有重大的经济效益和环境效益。     

Mobile load simulators – A tool to distinguish between the emissions due to abrasion and resuspension of PM10 from road surfaces

Mechanically produced abrasion particles and resuspension processes are responsible for a significant part of the PM10 emissions of road traffic. However, specific differentiation between PM10 emissions due to abrasion and resuspension from road pavement is very difficult due to their similar elemental composition and highly correlated variation in time. In this work Mobile Load Simulators were used to estimate PM10 emission factors for pavement abrasion and resuspension on different pavement types for light and heavy duty vehicles.From the experiments it was derived that particle emissions due to abrasion from pavements in good condition are quite low in the range of only a few mg·km^?1 per vehicle if quantifiable at all. Considerable abrasion emissions, however, can occur from damaged pavements. Resuspension of deposited dust can cause high and extremely variable particle emissions depending strongly on the dirt load of the road surface. Porous pavements seem to retain deposited dust better than dense pavements, thus leading to lower emissions due to resuspension compared to pavements with a dense structure (e.g. asphalt concrete). Tyre wear seemed not to be a quantitatively significant source of PM10 emissions from road traffic.     

Artificial intelligence modeling to evaluate field performance of photocatalytic asphalt pavement for ambient air purification

In recent years, the application of titanium dioxide (TiO₂) as a photocatalyst in asphalt pavement has received considerable attention for purifying ambient air from traffic-emitted pollutants via photocatalytic processes. In order to control the increasing deterioration of ambient air quality, urgent and proper risk assessment tools are deemed necessary. However, in practice, monitoring all process parameters for various operating conditions is difficult due to the complex and non-linear nature of air pollution-based problems. Therefore, the development of models to predict air pollutant concentrations is very useful because it can provide early warnings to the population and also reduce the number of measuring sites. This study used artificial neural network (ANN) and neuro-fuzzy (NF) models to predict NO_x concentration in the air as a function of traffic count (T_r) and climatic conditions including humidity (H), temperature (T), solar radiation (S), and wind speed (W) before and after the application of TiO₂ on the pavement surface. These models are useful for modeling because of their ability to be trained using historical data and because of their capability for modeling highly non-linear relationships. To build these models, data were collected from a field study where an aqueous nano TiO₂ solution was sprayed on a 0.2-mile of asphalt pavement in Baton Rouge, LA. Results of this study showed that the NF model provided a better fitting to NO_x measurements than the ANN model in the training, validation, and test steps. Results of a parametric study indicated that traffic level, relative humidity, and solar radiation had the most influence on photocatalytic efficiency.     

The effect of different surface materials on runoff quality in permeable pavement systems

Environmental Science and Pollution Research - To investigate the effect of different permeable pavement surface materials on the removal of pollutants from urban storm-runoff, six commonly surface...     

Experimental evaluation of the thermal performance of cool pavement materials in cold regions of China

Environmental Science and Pollution Research - The local thermal property evaluation of pavement materials has not received enough attention, making the implementation of cool material measures to...     

An overview on the properties of eco-friendly concrete paving blocks incorporating selected waste materials as aggregate

Environmental Science and Pollution Research - Paving block is a widely used pavement material due to its long service life, fast and easy production and easily replaced for maintenance purpose....     

Mechanical properties of steel slag replaced mineral aggregate for road base/sub-base application based Vietnam and Japan standard

Steelmaking slag is one of the most massive industrial by-products generated during steelmaking processes. This paper presents the current steelmaking slag production status and its potential to use as mineral aggregates in base/sub-base layer of road pavement. The mechanical properties of steelmaking slag were confirmed by the test method specified in Vietnam specification. The volume stability test of the slag was conducted based on JIS A 5015-2018 (Japanese Industrial Standard: Iron and steel slag for road construction). From the results, it was confirmed that steelmaking slag can satisfy all the mechanical requirements specified in Vietnam specification and the requirements regarding stability specified in JIS A 5015-2018. In addition, it was found that the elastic modulus of steelmaking slag applied as a base or sub-base layer in pavement was higher than that of the conventional graded aggregate made from mineral aggregate. Therefore, the thickness of pavement can be reduced by using steelmaking slag, and the construction cost can be lower.

     

Effects of studded tires on roadside airborne dust pollution in Niigata,Japan

Two series of dust samples, collected by Andersen impactors (denoted by AN) and low-volume air samplers (denoted by LV), were investigated with respect to roadside airborne dusts collected in two different periods in 1983. These were the periods

• 1.(i) with studded tires (February and March) and
• 2.(ii) without studded tires (October).

Multi-element determinations of these samples were made by neutron activation analysis and atomic absorption spectrometry. The total concentration of AN in roadside air for period (i) was about three times higher than for the period without studded tires. The lithophilic elements such as Na, Al, K, Ca, Ti, Fe and Th, and component-metal elements of stud tip, W and Ta, produced a significant increase in atmospheric concentration in winter. The contribution of pavement material, one of the most interesting components of airborne particles in this study, was related to total AN and LV by the chemical element balance method. It made up only 16 percent (9.1 μgm⁻³) of AN in October, compared with 46 percent (70.2 μgm⁻³) in February. It was also observed that the atmospheric concentrations of pavement debris to total LV decreased with the distance from the road to each sampling site.     

Analysis of the influence of urban form and materials on sensible heat flux — a case study of Japan's largest housing development “Tama New Town”

In this study, the relationship between the form and materials of urban blocks and sensible heat flux from total surfaces was analyzed in the case of `Tama New Town', which is one of the largest housing developments in Japan and is under continuing development. First, urban blocks were divided into five categories depending on the building plot types. The characteristics of the form and thermal properties of each building, as well as the land cover condition (area of vegetation, bare soil, asphalt pavement, and built area) of each category was considered. Furthermore, 6 urban blocks were selected for numerical simulation of heat balance of the total surfaces, and sensible heat flux from the total surfaces of each urban block on clear sky summer day was calculated. It was confirmed that the influence of the direction that buildings faced and floor area ratio was as great as that of building materials upon the amount of sensible heat flux in each urban block.     

Environmental interactions of Sulphlex pavement

Sulphlex, a mixture of elemental sulfur and plasticizers, has been considered for use as an asphalt substitute in road construction. Because this material contains substantial quantities of elemental sulfur, it is a potential substrate for growth of sulfur-oxidising bacteria. Experiments, performed to determine the susceptibility of Sulphlex in Sulphlex-containing media to degradation by Thiobacillus thiooxidans, resulted in breakdown of the Sulphlex material and concomitant production of acid. In concurrent studies, plants were grown in Sulphlex-amended soils. These plants exhibited higher sulfur content and reduced productivity as compared with plants grown in unamended soils, indicating that Sulphlex was being broken down in the soil and that the breakdown products were apparently having a detrimental effect on plant productivity. These experiments indicate that naturally occurring sulfur-oxidising bacteria have the potential to break down Sulphlex paving material, resulting in adverse effects on both the structural integrity of the pavement and the local environment.     

Analysis of the ability of water resources to reduce the urban heat island in the Tokyo megalopolis

Simulation procedure integrated with multi-scale in horizontally regional-urban-point levels and in vertically atmosphere-surface-unsaturated-saturated layers, was newly developed in order to predict the effect of urban geometry and anthropogenic exhaustion on the hydrothermal changes in the atmospheric/land and the interfacial areas of the Japanese megalopolis. The simulated results suggested that the latent heat flux in new water-holding pavement (consisting of porous asphalt and water-holding filler made of steel by-products based on silica compound) has a strong impact on hydrologic cycle and cooling temperature in comparison with the observed heat budget. We evaluated the relationship between the effect of groundwater use as a heat sink to tackle the heat island and the effect of infiltration on the water cycle in the urban area. The result indicates that effective management of water resources would be powerful for ameliorating the heat island and recovering sound hydrologic cycle there.     

基于最佳管理实践的中新生态城面源污染控制措施优选研究

基于最佳管理实践（BMP）理念和方法,以中新生态城为例,采用多属性决策分析方法的ELECTRE-Ⅲ方法和模型,采用VisualBasic语言自行编制辅助计算机程序,对该地区8种雨水控制管理措施进行了优化比选。优选结果表明,对于中新生态城,8种雨水控制管理措施的优选排序为：湿地〉地下蓄水库〉人渗沟〉可渗透路面砖〉道路边沟〉绿色屋顶〉下凹绿地〉绿化缓冲带。