scholarly journals Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

2016 ◽  
Vol 12 (2) ◽  
pp. 94-102 ◽  
Author(s):  
Daša Fullová ◽  
Daniela Đurčanská
Keyword(s):  
Particulate Matter ◽  
Chemical Composition ◽  
Road Traffic ◽  
Asphalt Pavement ◽  
Road Dust ◽  
Traffic Volume ◽  
Asphalt Mixtures ◽  
Laboratory Measurements ◽  
Experimental Laboratory ◽  
Wheel Tracking

Abstract The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

scholarly journals Investigation on Hamburg Wheel-Tracking Device Stripping Performance Properties of Recycled Hot-Mix Asphalt Mixtures

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4704
Author(s):  
Waqas Rafiq ◽  
Madzlan Bin Napiah ◽  
Muslich Hartadi Sutanto ◽  
Wesam Salah Alaloul ◽  
Zarisha Nadia Binti Zabri ◽  
...  
Keyword(s):  
Hot Mix Asphalt ◽  
Asphalt Pavement ◽  
Asphalt Mixtures ◽  
Asphalt Pavements ◽  
Recycled Asphalt ◽  
Persistent Problem ◽  
Moisture Stability ◽  
Tracking Device ◽  
Wheel Tracking ◽  
Hamburg Wheel Tracking

Moisture damage in hot mix asphalt pavements is a periodic but persistent problem nowadays, even though laboratory testing is performed to identify different moisture-susceptible mixtures. In this study, a Hamburg Wheel Tracking device (HWTD) was used for rutting tests which were conducted on control and a high percentage of recycled asphalt pavement (RAP), i.e., 30%, 50% and 100% of virgin mixtures, under air dry and water-immersed conditions. Similarly, the extracted bitumen from RAP was tested for binder physical properties. Results showed that the asphalt mixtures containing RAP have less rut depth as compared to the control mix both in air dry and immersion conditions and hence showed better anti-rutting properties and moisture stability. Stripping performance of control and RAP containing mixtures was also checked, concluding that the RAP mixture was greatly dependent on the interaction between the binder (virgin plus aged) and aggregates.

scholarly journals Air pollution in the city of Prince George: Chemical analysis of particulate matter (PM2.5) contaminants

2020 ◽  
Author(s):  
◽  
Sahar Ebadzadsahraei
Keyword(s):  
Air Pollution ◽  
Particulate Matter ◽  
Chemical Composition ◽  
Road Dust ◽  
Atmospheric Particulate Matter ◽  
Chemical Compositions ◽  
Cobalt Nickel ◽  
The City ◽  
Nickel Manganese ◽  
Pm2.5 Concentration

Air pollution has been an ongoing issue for the City of Prince George, the largest city in northern British Columbia. This research was designed to measure the chemical composition of atmospheric Particulate Matter (PM2.5) in a Prince George neighborhood (i.e., downtown). The main objective of this research was to determine the PM2.5 chemical compositions in two distinct periods: warm and cold. Overall, 153 samples were collected from January to August 2018, using personal air samplers. The highest concentration of PM2.5 was recorded during the 2018 summer wildfires. Chemical composition of the PM2.5 air samples were studied with respect to Cadmium, Potassium, Mercury, Sodium, Lead, Chromium, Iron, Cobalt, Nickel, Manganese, Copper, Titanium, Molybdenum, Phosphorus and Sulphur, in order to evaluate potential sources of air pollutants in the city. The results of this study were compared with PM2.5 averages from other Canadian and international cities. The possibilities of the contribution of some local industrial sources such as pulp and paper, biomass burning, transportation and road dust, on PM2.5 concentration and chemical composition were discussed.

Suitability of Asphalt Pavement Analyzer for Predicting Pavement Rutting

2000 ◽  
Vol 1723 (1) ◽  
pp. 107-115 ◽  
Author(s):  
Bouzid Choubane ◽  
Gale C. Page ◽  
James A. Musselman
Keyword(s):  
Performance Prediction ◽  
Field Data ◽  
Asphalt Pavement ◽  
Evaluation Process ◽  
Field Measurements ◽  
Asphalt Mixtures ◽  
Test Results ◽  
Asphalt Mixes ◽  
Tracking Device ◽  
Wheel Tracking

Findings are summarized from an investigation performed to evaluate the suitability of a wheel-tracking device known as the asphalt pavement analyzer (APA) for assessing the rutting potential of asphalt mixes. The evaluation process consisted of correlating the APA’s predicted rutting with known field measurements. The correlation between beam and gyratory samples and the testing variability were also investigated. In addition, the APA test results were compared with those obtained using the Georgia loaded-wheel tester. The findings of this investigation indicated that the APA may be an effective tool to rank asphalt mixtures in terms of their respective rut performance. However, for each mixture type, the APA testing variability was significant between tests and between the three testing locations within each test. Differences in rut measurements of up to 4.7 and 6.3 mm were recorded for beam and gyratory samples, respectively. Therefore, using the APA as a clear pass-or-fail criterion for performance prediction purposes of asphalt mixtures may not be appropriate at this time. It should be noted that these findings are based on data collected on three mixes. Therefore, it is suggested that the APA testing variability (testing and testing locations within the device) be further assessed with a wider range of mixtures. The intent of such an assessment should not only be to correlate the APA results with field data but also to develop potential pass-or-fail limits and procedures.

Research and Application of Anti-Rutting in the Asphalt Mixtures

2012 ◽  
Vol 594-597 ◽  
pp. 1467-1470 ◽  
Author(s):  
Xiu Hua Yang
Keyword(s):  
Axial Load ◽  
Asphalt Pavement ◽  
Traffic Volume ◽  
Asphalt Mixtures ◽  
Service Capacity ◽  
Highway Traffic ◽  
Structure Damage ◽  
Main Factors ◽  
Load Composition ◽  
Large Flow

with the development of our country highway traffic to large flow, large axle load and channelized traffic direction, traffic volume and the changes of axial load composition to the present asphalt pavement structure, causing the pavement service capacity declines, structure damage occurs early, rut problem is one of the main factors of asphalt pavement quality, so the anti-rutting in the asphalt mixtures were studied in this paper.

scholarly journals The impact of measures to reduce ambient air PM<sub>10</sub> concentrations originating from road dust, evaluated for a street canyon in Helsinki

2019 ◽  
Vol 19 (17) ◽  
pp. 11199-11212 ◽  
Author(s):  
Ana Stojiljkovic ◽  
Mari Kauhaniemi ◽  
Jaakko Kukkonen ◽  
Kaarle Kupiainen ◽  
Ari Karppinen ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Street Canyon ◽  
Dust Emission ◽  
Road Dust ◽  
Ambient Air ◽  
Air Quality Measurements ◽  
Emission Models ◽  
The Impact ◽  
Quality Measurements

Abstract. We have numerically evaluated how effective selected potential measures would be for reducing the impact of road dust on ambient air particulate matter (PM10). The selected measures included a reduction of the use of studded tyres on light-duty vehicles and a reduction of the use of salt or sand for traction control. We have evaluated these measures for a street canyon located in central Helsinki for four years (2007–2009 and 2014). Air quality measurements were conducted in the street canyon for two years, 2009 and 2014. Two road dust emission models, NORTRIP (NOn-exhaust Road TRaffic Induced Particle emissions) and FORE (Forecasting Of Road dust Emissions), were applied in combination with the Operational Street Pollution Model (OSPM), a street canyon dispersion model, to compute the street increments of PM10 (i.e. the fraction of PM10 concentration originating from traffic emissions at the street level) within the street canyon. The predicted concentrations were compared with the air quality measurements. Both road dust emission models reproduced the seasonal variability of the PM10 concentrations fairly well but under-predicted the annual mean values. It was found that the largest reductions of concentrations could potentially be achieved by reducing the fraction of vehicles that use studded tyres. For instance, a 30 % decrease in the number of vehicles using studded tyres would result in an average decrease in the non-exhaust street increment of PM10 from 10 % to 22 %, depending on the model used and the year considered. Modelled contributions of traction sand and salt to the annual mean non-exhaust street increment of PM10 ranged from 4 % to 20 % for the traction sand and from 0.1 % to 4 % for the traction salt. The results presented here can be used to support the development of optimal strategies for reducing high springtime particulate matter concentrations originating from road dust.

scholarly journals Rutting and moisture-induced damage potential of foamed warm mix asphalt (WMA) containing RAP

2021 ◽  
Vol 6 (3) ◽  
Author(s):  
Mohammad Ashiqur Rahman ◽  
Rouzbeh Ghabchi ◽  
Musharraf Zaman ◽  
Syed Ashik Ali
Keyword(s):  
Asphalt Pavement ◽  
Warm Mix Asphalt ◽  
Environmental Benefits ◽  
Reclaimed Asphalt Pavement ◽  
Chemical Additives ◽  
Flow Number ◽  
Damage Potential ◽  
Asphalt Mixes ◽  
Reclaimed Asphalt ◽  
Wheel Tracking

AbstractDespite significant economic and environmental benefits, performance of warm mix asphalt (WMA) containing reclaimed asphalt pavement (RAP) remains a matter of concern. Among the current WMA technologies, the plant foaming technique (called “foamed WMA” in this study) has gained the most attention, since it eliminates the need for chemical additives. In the present study, the laboratory performance, namely rutting and moisture-induced damage potential of foamed WMA containing RAP were evaluated and compared with those of similar hot mix asphalt (HMA) containing identical amount of RAP. Dynamic modulus, Hamburg wheel tracking (HWT) and flow number tests were performed to assess the rutting resistance of the mixes. Also, stripping inflection point from HWT tests and tensile strength ratio after AASHTO T 283 and moisture induced sensitivity test (MIST) conditioning were used to evaluate the moisture-induced damage of asphalt mixes. It was found that MIST conditioning effectively simulates the moisture-induced damage and can capture the propensity of asphalt mixes to moisture damage more distinctly compared to AASHTO T 283 method due to application of cyclic loadings. The foamed WMA was found to exhibit higher rutting and moisture-induced damage potential due to lower mixing and compaction temperatures compared to HMA. However, the increase in RAP content was found to reduce rutting and moisture-induced damage potential for WMA. Therefore, the lower stiffness of foamed WMA may be compensated with the addition of stiffer binder from RAP.

scholarly journals Effects of Evocative Audio-Visual Installations on the Restorativeness in Urban Parks

2021 ◽  
Vol 13 (15) ◽  
pp. 8328
Author(s):  
Massimiliano Masullo ◽  
Luigi Maffei ◽  
Aniello Pascale ◽  
Vincenzo Paolo Senese ◽  
Simona De Stefano ◽  
...  
Keyword(s):  
Social Inclusion ◽  
Road Traffic ◽  
Traffic Noise ◽  
Human Perception ◽  
Urban Parks ◽  
Well Being ◽  
Road Traffic Noise ◽  
Beneficial Effects ◽  
Positive Effects ◽  
Experimental Laboratory

Road traffic noise is responsible for several negative health effects for citizens in modern cities. Inside urban parks, which citizens use for social inclusion and cohesion, psychological and physical restoration, and physical activities, road traffic noise may significantly reduce the potential of these places to induce or enhance well-being. Although access restriction schemes and screens could be effective solutions to limit noise inside urban park areas, preserving their potential regenerative role may engender mobility, social, aesthetic, and architectural issues. Due to the positive effects that natural elements and water sounds can have on human perception, and based on the previous findings of the beneficial effects of audio-visual installations, this paper investigates the possibility of using audio-visual installations that simply evoke some natural features to improve the restoration of individuals inside urban parks. The study has been carried out using immersive virtual environments in two different experimental laboratory sessions in Hong Kong (China) and Aversa (Italy). The results showed that the positive effects provided by evocative installations were similar to those provided by traditional installations. Furthermore, the effects on the restoration increased as the installations became larger and included enveloping shapes. Furthermore, we found that the amount of evocative water installations’ material was responsible for changes in restoration. In contrast, the Chinese groups were less influenced by these installations.

scholarly journals COVID Lockdowns, Social Distancing, and Fatal Car Crashes: More Deaths on Hobbesian Highways?

2020 ◽  
Vol 4 (3-4) ◽  
pp. 238-259 ◽  
Author(s):  
Marshall W. Meyer
Keyword(s):  
World War Ii ◽  
Traffic Safety ◽  
Motor Vehicle ◽  
Road Traffic ◽  
Research Question ◽  
Traffic Volume ◽  
Similar Data ◽  
World War ◽  
Social Distancing ◽  
The Usa

Abstract Research Question What happened to US traffic safety during the first US COVID-19 lockdown, and why was the pattern the opposite of that observed in previous sudden declines of traffic volume? Data National and local statistics on US traffic volume, traffic fatalities, injury accidents, speeding violations, running of stop signs, and other indicators of vehicular driving behavior, both in 2020 and in previous US economic recessions affecting the volume of road traffic. Methods Comparative analysis of the similarities and differences between the data for the COVID-19 lockdown in parts of the USA in March 2020 and similar data for the 2008–2009 global economic crisis, as well as other US cases of major reductions in traffic volume. Findings The volume of traffic contracted sharply once a COVID-19 national emergency was declared and most states issued stay-at-home orders, but motor vehicle fatality rates, injury accidents, and speeding violations went up, and remained elevated even as traffic began returning toward normal. This pattern does not fit post-World War II recessions where fatality rates declined with the volume of traffic nor does the 2020 pattern match the pattern during World War II when traffic dropped substantially with little change in motor vehicle fatality rates. Conclusions The findings are consistent with a theory of social distancing on highways undermining compliance with social norms, a social cost of COVID which, if not corrected, poses potential long-term increases in non-compliance and dangerous driving.

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