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Gravel roads deterioration having absence of maintenance is one of the serious issue and common problem in the world. In order to achieve the objectives of the study, the researchers were used questioner survey. To achieve this, first identified the road sections those having lack of maintenance on time existed in the study area. Then the representative road (Sarbo-Busa, Saka-Ushane and Buxure-Sanxama) and questioner surveys samples have been selected by non-probabilistic purposive and systematic sampling respectively. The questioner’s survey was focused on identifying the causes of absence of maintenance and pre-conditions considered. Questioner survey was analyzed by RII. The absence of maintenance was occurred due to lack of budget fund, poor management, lack of skilled manpower, lack of good material quality, lack of regular inspections, poor working environments. The pre-conditions considered while maintaining the gravel roads are: Cost of maintenance, class as the road, maintenance schedule, skilled manpower, topography, number of road users, traffic volume, and economic standards of the society and location of the road from the center. In Jimma zone the deteriorations of gravel roads has been increasing with the absence of maintenance time.

Gravel road safety is a crucial area of road safety since gravel roads represent a substantial proportion of the entirety of the nation’s roadway network. Also, gravel roads pose inherent hazards t...

Due to importance of developing the North and Arctic territories, it is essential to ensure working capacity of machinery in cryolithozone. To solve these problems, it is necessary to study accumulation of structural damage and changes in material properties. The purpose of this article is to study influence of operation in the northern roads conditions on fatigue damage, brittle fracture resistance and the working capacity of a leaf spring of a KAMAZ truck widely used in Yakutia. Methods of mathematical statistics, metallography, microindentation, standard mechanical tests, etc. were applied. Results of analysis of distribution of the KAMAZ vehicle springs failures on the months of the year are given, taking into account the seasonal changes in a profile of the typical for Yakutia gravel road. To assess the fatigue damage of metal, the structural and statistical study of microhardness (microdamage) and porosity (mesodamage) was carried out. Impact toughness values were determined and it was found that the accumulated damage did not lead to metal embrittlement at low temperatures. The more significant impact of the cryolithozone road microprofile on the working capacity of the KAMAZ truck springs as compared to the factor of the low temperatures has been substantiated.

An analysis of vibration signals has been proposed for a personal gasoline-engine car while driving on three types of roads including paved road, concrete road, and gravel road. The wired sensors are placed upon three positions inside the passenger room: right-front seat surface, left-front seat surface, and rear seat surface. The objectives of this analysis are to differentiate the corresponding vibration reflecting from driving upon three types of roads and to differentiate the vibration at three different positions of sensors inside the passenger room. The signal analysis technique of Fast Fourier Transform is utilized in this analysis, the obtained spectrum is investigated to extract the dominant peaks. Thereafter, the averages of the peak values are calculated for six different engine speeds ranging from 0-30 km/h. These averaging calculations are based on 50 five-second-length samples of vibration signals. To achieve the first objective, the experimental results insist that the highest peak values are mostly of the gravel road, meanwhile, the lowest peak values are of the paved road. To accomplish the second objective, the experimental results strongly confirm the following comparisons. In the case of paved road, the highest peak values are at the rear seat surface, meanwhile, in the case of concrete road, the highest peak values are at the left-front seat surface. Finally, in the case of gravel road, the highest peak values are at the rear seat surface. In conclusion, this study confirmed that the proposed approach can be used to differentiate the signal features of all scenarios.

This study developed a model to select the optimum sections of unpaved roads for chemical treatments as dust suppressants within a limited budget. In the state of Wyoming, more than 19,312 ...

In 2009, pulp mill fly ash was used for stabilizing the road base of a low-volume gravel road. Six years after stabilization, a two-year monitoring program and a complementary study were conducted ...

In the northern Great Plains, a potential road dust abatement is the application of oil-well produced water, also known as “brine.” However, little is known about the effectiveness of brine or its potential impacts on dispersion of road materials and the creation of dusts. This study aimed to investigate how sodium adsorption ratios (SAR), electrical conductivity (EC), and Ca/Mg ratios of simulated and non-simulated brine influenced dispersive reactions of three mineralogically different gravel road fine fractions. Ca/Mg ratios had little to no significant influence on the outcome of dispersion. Irrespective of the SAR or clay mineralogy, a threshold EC of 4 dS m−1 was sufficient to control road fine fraction dispersion. Actual oil-well produced water effect on dispersion followed the same order as that treated by simulated solution and the dispersion value can be well-predicted from EC. This information is useful to managers, regulators, scientists, and industry professionals considering the use of brine as a road dust control abatement.

The Arba Rekete-Gelemso gravel Road section is affected by the presence of expansive soil, this soil has shrinking and swelling behavior due moisture fluctuation. The main objective of this research work is to investigate the Characterization of Borrow materials for embankment fill and capping layer based on their index and strength properties for Road Construction of the proposed route. In order to achieve the objectives, field investigation and nine (9) samples were also collected from the identified borrow area and laboratory test analysis were performed such as, Atterberg limits, compaction, CBR and percentage of swell tests. ERA‘s and AASHTO’s standard technical specifications have been used to interpret the data by integrating the field with laboratory test results. The subgrade soil of route, having liquid limit value greater than 60% and plastic index value greater than 30% and CBR value less than 5%, at Chainage km 0+000-4+000, 5+900-8+000, 9+400-12+900, 13+500-14+000, 15+000-16+000, 17+100-17+600, 18+500-20+500, 21+500-34+900, and 35+200-47+000 unsuitable. The index and strength properties of the borrow materials fulfill the requirement for embankment fill and subgrade improvements. Finally, all unsuitable subgrade soil along the study route corridor are recommended to remove and replace with suitable and non-expansive subgrade materials, since enormous amount of selected fill materials that fulfill the requirements for subgrade soils improvement are available nearby the study area.

The following paper presents results of research carried out on oiled gravel aggregate. In Russia, the oil-treated aggregate mixture is called “loose-bound organic-mineral mixture” (hereinafter abbreviated as LOM). The aim of the research was to explore the possibility of using oil waste products and their heavy residues generated during oil transportation as a binder in oil-treated gravel aggregate or LOM. Currently, this waste is not used anywhere, it is widely burned, polluting the environment. Studies were carried out using Infra-red spectroscopy of samples of the original oil waste, heavy residues of oil waste and road oil bitumen of BND 90/130 quality type. The fractional composition of oil wastes and their heavy residues was studied during their distillation by heating to a temperature of +335 °C. It was found that for preparing LOM it is more effective to use oil residues. The number of LOM compositions samples were prepared and their main physical and mechanical indicators were determined. Based on the tests, it was concluded that the residues of oil waste can be used as a binder in the composition of LOM such as oil-treated gravel.

Increased traffic flow on low-volume gravel roads and deficiencies of national road infrastructure, are increasingly apparent in Lithuania. Gravel roads do not comply with requirements, resulting in low driving comfort, longer travelling time, faster vehicle amortization, and dustiness. The control of dustiness is one of the most important road maintenance activities on gravel roads. Another important issue is the assurance of required driving comfort and safety. Soft asphalt and Otta Seal technologies were proposed as a sustainable solution for the improvement of low-volume roads in Lithuania. Five gravel roads were constructed with soft asphalt, and 13 gravel roads were sealed with double Otta Seal, in 2012. The main aim of this research was to check soft asphalt and double Otta Seal’s ability to self-heal, on the basis of the results of the qualitative visual assessment of pavement defects and distress. The qualitative visual assessment was carried out twice a year following the opening of the rehabilitated road sections. The results confirmed soft asphalt and double Otta Seal’s ability to self-heal. The healing effect was more than 13% and 19% on roads with soft asphalt and double Otta Seal, respectively. In addition, on some roads, all cracks observed in spring self-healed during summer.

Gravel road dust has significant health effect. The study was conducted to assess road dust suppression effect of molasses stillage in gravel at a Sugarcane Estate in Zimbabwe. Three, 2 km long gravel road sections (steep, sloping and gentle) had the following dust suppression treatments applied to 500m long segments: (i) molasses stillage, (ii) water and (iii) control. Data on dust deposition rates were subjected to Analysis of Variance (ANOVA) to compare treatment means. Mean road dust deposition rates ranged from 998.46±50.04 to 6184.02±257 mg/m

Road transport is one of the biggest soil polluter. There are a lot of investigations of soil pollution near highways, but soil pollution near gravel roadsides needs more experimental research. In this experimental study we selected gravel road Juseviciai – Būdvietis – Derviniai and analyzed soil pollution near this road. Soil samples were collected on both sides of the road by making the transversal profile, the sampling points move away of the road at a distance 1; 2; 5; 10 meters, the samples were collected in 600 meters long strip. All samples were collected by using the envelope principle, samples were taken from the top of the soil layer 0 - 10 cm depth. It was established that Mn concentration in the soil sample, which was taken from the middle of gravel road carriageway, reached 238,5 mg/kg – it means 1,79 times less than background value. This value is more than 6 times less than maximum allowed concentration and quit close to the values, which were established on both sides in the soil close to gravel road. The modelling of Mn concentration where made in appropriate scale of mathematical model – 15 meter to both sides of gravel road, the width of the road – 4 meters. The simulated soil volume is 34 x 14 meters, the soil type - medium-coarse sandy loam. It was modeled that after one year Mn concentration in the soil, close to gravel road remains 1,8 times less than background value (at a constant Mn emission in the environment). Moving away from driveway till 10-15 meters the concentration of Mn decrease to 2,48 less in the soil depth of 0,5 m. After 10 years this concentration will reach 1 meter depth. Bet there would be no changes of Mn concentration in the groundwater level. DOI: https://doi.org/10.3846/enviro.2017.036

Roughness is a dynamic property of the gravel road surface that affects safety, ride comfort as well as vehicle tyre life and maintenance costs. A rapid survey of gravel road condition is fundamental for an effective maintenance planning and definition of the intervention priorities.Different non-contact techniques such as laser scanning, ultrasonic sensors and photogrammetry have recently been proposed to reconstruct three-dimensional topography of road surface and allow extraction of roughness metrics. The application of Microsoft Kinect™ depth camera is proposed and discussed here for collection of 3D data sets from gravel roads, to be implemented in order to allow quantification of surface roughness.The objectives are to: i) verify the applicability of the Kinect sensor for characterization of different forest roads, ii) identify the appropriateness and potential of different roughness parameters and iii) analyse the correlation with vibrations recoded by 3-axis accelerometers installed on different vehicles. The test took advantage of the implementation of the Kinect depth camera for surface roughness determination of 4 different forest gravel roads and one well-maintained asphalt road as reference. Different vehicles (mountain bike, off-road motorcycle, ATV vehicle, 4WD car and compact crossover) were included in the experiment in order to verify the vibration intensity when travelling on different road surface conditions. Correlations between the extracted roughness parameters and vibration levels of the tested vehicles were then verified. Coefficients of determination of between 0.76 and 0.97 were detected between average surface roughness and standard deviation of relative accelerations, with higher values in the case of lighter vehicles.

Measurement of particle-size distribution (PSD) of soil with large-sized particles (e.g., 25.4 mm diameter) requires a large sample and numerous particle-size analyses (PSAs). A new method is needed that would reduce time, effort, and cost for PSAs of the soil and aggregate material with large-sized particles. We evaluated a nested method for sampling and PSA by comparing it with the methods that follow the American Association of State Highway and Transportation Officials (AASHTO) standard T88-00 and the American Society for Testing and Materials (ASTM) standard D422-63. Using 33 forest road aggregate samples from the Clearwater National Forest in northern Idaho, the nested method required much less laboratory time and effort and resulted in similar PSA values, except for the 0.149 mm (No. 100) sieve, where the smallest particle-size fraction (PSF) values (1.30% and 1.39%) were observed. The nested method shows great potential for determining PSDs of the soil and aggregate material with large-sized particles and should be tested on other forest soils and road aggregates. The nested sampling and analysis method allows for the same number of samples to be collected but requires less laboratory time, making it more efficient and economical for testing the soil and aggregate material with large-sized particles such as forest road aggregate.

Gravel roads are majorly affected by deterioration which manifests as loss of gravel materials due to traffic and environmental conditions. District Road Maintenance Managers are faced with competing investment demands to maintain gravel road networks in the best condition due to inadequate intelligent techniques of evaluating the roadway performance. The aim of evaluating the road network performance is to reduce the rate of deterioration so that maintenance interventions could be extended. Road condition data is a precursor for road monitoring and is collected on a periodic basis by road authorities to assist in transportation planning. The primary objective of this paper was to evaluate and analysis the trend of Botswana gravel road condition which best captures the effects of gravel road condition influencing factors. This was achieved by carrying out exploratory statistical analysis. Gravel road condition data were collected through the Botswana Roads Department covering 2002, 2005 and 2008 for Botswana district gravel road networks. The variables required for the analysis were clustered and pre-processed to determine their suitability. The analysis results gave a broad overview of the extent to which gravel road condition trends lend credence to their usefulness in district transportation networks monitoring in Botswana.

The Wyoming technology Transfer Center (WYT2/ LTAP) is currently in the process of developing a Gravel Roads Management System (GRMS) in Wyoming. One of the major components of this new GRMS is developing a comprehensive optimization methodology for Maintenance and Rehabilitant (M&R) activities. To support the new optimization methodology, this research study established multiple performance models to predict the deterioration patterns of gravel roads in Wyoming. Condition data, in addition to the average deterioration rates, for approximately 1931km (1200 miles) of gravel road segments were used to develop these models. A probabilistic modeling approach using Markov Chains (MC) was adopted in this study to establish these prediction models. The developed prediction equations obtained from fitting these models include all the possible deterioration modes of gravel roads such as potholes, washboards, loose aggregate, and rutting. Generally, it was found that the average service life of a gravel road is around 12 months without any maintenance intervention. In addition, potholes, rutting, and washboards are the main failure modes for these types of roads.

We recorded 94 sound-response events at 3 adult-occupied northern goshawk (Accipiter gentilis) nests 78m, 143m, and 167m from the nearest United States Forest Service maintenance level 3, improved gravel road on the Kaibab Plateau in northern Arizona. During 4 test sessions on 7, 8, 10, and 11 June 2010, we recorded 60 experimentally controlled logging trucks; 30 non-experimental, civilian, fixed- winged aircraft; 3 non-experimental, passing cars; and 1 all-terrain vehicle (ATV). Logging truck sound, principally engine and exhaust, was concentrated in the 63Hz and 80Hz, 1/3-octave frequency bands. Aircraft sound was concentrated in the 100Hz and 125Hz, 1/3-octave frequency bands. Logging truck noise levels varied among nest sites and with distance from roads. At 167m from the closest road, the logging truck averaged approximately 8 decibels (dB, all decibel levels C-weighted, adjusted, 1s, equivalent sound level, CLEQ) quieter than aircraft. At 143m, the logging truck was approximately 3dB quieter than passing aircraft. Only at 78m was logging truck noiselouder on average than aircraft, by approximately 6dB. Average aircraft noise levels for each day of testing ranged between 45.6dB and 67.9dB and when averaged across the entire study period, varied little among the 3 test sites, 60.1-65.6dB. On average, our test logging truck (61.9dB) wasnolouderthanpassingaircraft (62.3dB),whichgoshawks generallyignored. The loggingtruck resulted in 27% no response and 73% alert (head turning) response, passing aircraft resulted in 90% no response and only 10% alert response, and the cars and ATV combined resulted in 50% each for no response and alert response. Goshawk alert response rates were inversely proportional to nest distance from the nearest road, decreasing from 91% to 57% alert between 78m and 167m. No movements or flushes were associated with either our experimental testing or passive recording of other vehicular noise stimuli. All tested pairs of goshawks successfully fledged young. Because logging truck noise had no effect on northern goshawks nesting along level 3, improved gravel roads on the Kaibab Plateau, restriction of log hauling and other road- based travel activities on similar roads within post-fledging family areas (PFAs) appears unnecessary based on the type and extent of our testing. 2013 The Wildlife Society.

Materials used to reduce dustiness on gravel roads affect both the gravel road surfacing and the neighbouring vegetation. Materials used to reduce dustiness may access vegetation directly (when sprayed on gravel roads) and indirectly (when leached out by precipitation). The investigation examined a new substance, the aqueous solution Safecote (of different concentrations) and its mixtures with calcium chloride. 10%, 20% and 30% concentrations of Safecote and 36.5% of calcium chloride were used. The mixture ratio was 1:1 by volume. The investigation addressed the impact of the applied solutions on the length and viability of the above-ground part of plants. The timothy grass, white clover and crimson clover species of grass vegetation were selected for the investigation. The choice was determined by the fact that these species frequently grow in pastures by gravel roads. As it was determined during the investigation the viability of the selected plants in non-contaminated soil was 85-89%, in soil contaminated with dust reducing agent was 67-88% using solution Safecote, and 0-1% when applying mixtures of solutions. After 6 weeks of growth the length of above-ground part was 6.41-8.57 cm in uncontaminated soil, 4.22-8.18 cm in soil contaminated with Safecote solution and 0.00-2.07 cm in soil contaminated with the mixture.

The Bakken region of western North Dakota and Montana from January 2012 to December 2013 saw an increase of 3368 oil wells, causing a major increase in road dust emissions. A portion of the energy extraction in the Bakken occurs in the wetland rich Prairie Pothole Region, and there is little information on gravel road dust emissions or the ecological impacts. The objectives of this study were to (1) estimate surface loading of gravel road dust during different times of year and at different distances from the road, (2) evaluate dust loading effects on surface water quality, and (3) evaluate the impact of dust deposition on wetland soils. Ten wetlands were tested in the energy impacted area and ten in an adjacent area without energy development. There was a 355 % increase in dust loading 10 m from the road in the energy impacted area compared to an area without energy development; meanwhile, there was only a 46 % increase in dust loading 40 m from the road. This loading resulted in an annual deposition of 647 g/m2 of gravel road dust close to the road. However, the effect of dust loading on the water quality and soils of wetlands was minimal when compared to wetlands not impacted by increased gravel road dust. The finding of minimal effect on wetland resources from increased road dust fills a knowledge gap in the Bakken on how energy development alters the environment.

The heat stabilities of embankment on the high temperature permafrost regions in the eastern Tibetan Plateau without climate warming and with air temperature rising speed of 0.04°C/a were modeled, and the heights of embankment were discussed and figured out, comparatively and respectively for asphalt-paved, concrete and gravel road surface, according to the natural geographic and geologic conditions in the high temperature permafrost regions in the district. The different confined conditions about embankment critical heights with climate warming and without climate warming were discussed in the paper. Finally, the result had been obtained by numerical calculation: in the high temperature area, for the two types of laying of cement concrete and gravel surface road, the two critical heights of the thermal stable conditions were (road operation for 30 years), respectively, do not consider climate change as 2.5 m and 2.0 m, consideration of climate change were 3.5 m and 3.0 m.

The problem of gravel road dustiness is quite acute. In order to minimize harmful environmental components and to conduct dust reduction tests, molasses materials were chosen. Using the molasses materials of a new generation (solution Safecote) in the Lithuanian market, the obtained results of dustiness have reflected a reduction in particulate matter in the air. During the experiment, gravel road pavement was treated with different degrees of concentration (10%, 20%, 30%) in solution “Safecote” at a driving speed of 30 km/h. Dustiness was measured at different distances from the road (0 m, 1 m, 2 m, 3 m). The undertaken study showed that the concentrations of particulate matter varied under changing weather conditions (air temperature, humidity, wind speed, atmospheric pressure). The statistical analysis of the received data has revealed that dustiness weakly correlates with temperature (correlation coefficient ranged from 0.12 to 0.67) moving from the road, the correlation coefficient of moisture is negative, a larger distance from the road increases inverse correlation (the correlation coefficient ranges from –0.02 to –0.85), negative correlation decreases moving from the road at a speed of the wind (from –0.72 to –0.06) and pressure correlation remains volatile (from –0.44 to 0.44). Santrauka Žvyrkelių dulkėtumo problema yra gana aktuali. Norint kuo mažiau kenkti aplinkos komponentams, dulkėtumo mažinimo tyrimams buvo pasirinkta medžiaga melasos pagrindu. Naudojant Lietuvos rinkoje gana naują melasos pagrindu pagamintą medžiagą (tirpalą „Safecote“) gauti dulkėtumo rezultatai parodė kietųjų dalelių ore mažėjimą. Tyrimų metu žvyrkelis buvo apdorotas skirtingomis tirpalo „Safecote“ koncentracijomis (10 %, 20 %, 30 %), аutomobiliai važiavo 30 km/h greičiu. Dulkėtumas matuotas skirtingais atstumais nuo kelio (0 m, 1 m, 2 m, 3 m). Atliekant tyrimus, pastebėta, kad kietųjų dalelių koncentracija kito, kintant oro sąlygoms (oro temperatūrai, oro drėgmei, vėjo greičiui, atmosferos slėgiui). Atliekant statistinę gautų duomenų analizę nustatyta, kad dulkėtumas tolstant kuo kelio su temperatūra mažai susijęs (temperatūros koreliacijos koeficientas svyravo nuo 0,12 iki 0,67), drėgmės koreliacijos koeficientas buvo neigiamas, o tolstant nuo kelio atvirkštinė koreliacija smarkėjo (koreliacijos koeficientas svyravo nuo –0,02 iki –0,85), tolstant nuo kelio vėjo greičiu neigiama koreliacija mažėjo (nuo –0,72 iki –0,06), o slėgio koreliacinis ryšys buvo nepastovus (nuo –0,44 iki 0,44).

Because of the ever-increasing cost associated with asphalt repaving, interest has been growing in turning back deteriorating asphalt roadways into maintainable aggregate driving surfaces. For more than 10 years, Pennsylvania's Dirt and Gravel Road Maintenance Program has funded projects that use environmentally sensitive maintenance techniques to reduce sediment pollution on unpaved roads while providing low-cost, long-range road maintenance solutions. The Center for Dirt and Gravel Road Studies at Pennsylvania State University has worked with various state and local entities on projects designed to convert these deteriorated asphalt roadways into durable, maintainable gravel surfaces, with a focus on reducing the environmental concerns related to road runoff. The purpose of this paper is to provide a detailed accounting of one such project. Several accepted options are available to accomplish this task. For this project, the full-depth reclamation process that uses chemical stabilization techniques was selected as the methodology to be demonstrated. As the project progressed, several site-specific challenges were encountered and ultimately resulted in a change in the tactics employed to effect the conversion from asphalt to gravel successfully. The results of the study emphasize the importance of properly evaluating preconstruction site conditions to determine the best methodology to be employed and of providing for flexibility in the design criteria and specifications.

Rural roads are an important part of the world’s transportation infrastructure as they provide connectivity to the major roads and highways. Long-term performance of pavement structures is significantly impacted by enhancement in the stability of the underlying soils. Conventionally, most of the rural roads are composed of compacted sub-grade layer. On the other hand, for higher volume road design, soil subgrades are expected to maintain load bearing strength under wet conditions, resist the weathering effect over its design life, and reduce permeability. The main objective of this research is to improve the strength of the sub-grade, which helps to construct stabilized gravel road for low volume traffic and reduce the crust thickness of the pavement layers of higher traffic volume using soil stabilized with nanomaterials and cement. In this article, performance improvement and improved design of a rural road using nanomaterials along with cement combination is presented. Results showed that clayey sand (SC) treated with nanomaterials have beneficial effects on their engineering properties, increased strength and stiffness, and enhanced durability. By using a combination of nanomaterials and cement, the California Bearing Ratio (CBR) of the soil increased to 18 times the original CBR and also improved the unconfined compressive strength (UCS) and durability of the soil. On the basis of these results, an improved design approach for low traffic and high traffic volume roads was done, and it is suggested that reduction in the crust thickness of the pavement layers is possible by using stabilized soil, and only stabilized gravel roads can be constructed for low traffic volume or rural roads.

Traffic-generated fugitive dust on gravel roads impairs visibility and deposits on the adjacent environment. Particulate matter smaller than 10 μm in diameter (PM10) is also associated with human health problems. Dust emission strength depends on the composition of granular material, road moisture, relative humidity, local climate (precipitation, wind velocity, etc.), and vehicle characteristics. The objectives of this study were to develop a reliable and rapid mobile methodology to measure dust concentrations on gravel roads, evaluate the precision and repeatability of the methodology and correspondence with the currently used visual assessment technique. Downwind horizontal diffusion was studied to evaluate the risk of exceeding the maximum allowed particulate matter concentration in ambient air near gravel roads according to European Council Directive [European Council Directive 1999/30/EC of 22 April 1999 relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. Official Journal of the European Communities. L163/41.]. A TSI DustTrak Aerosol Monitor was mounted on an estate car travelling along test sections treated with various dust suppressants. Measured PM10 concentrations were compared to visual assessments performed at the same time. Airborne particles were collected in filters mounted behind the vehicle to compare the whole dust fraction with the PM10 concentration. For measuring the horizontal diffusion, DustTraks were placed at various distances downwind of a dusty road section. The mobile methodology was vehicle and speed dependent but not driver dependent with pre-specified driving behaviours. A high linear correlation between PM10 of different vehicles makes relative measurements of dust concentrations possible. The methodology gives continuous data series, mobility, and easy handling and provides fast, reliable and inexpensive measurements for estimating road conditions to make road maintenance more efficient. Good correlations between measured PM10-values, visually assessed dust generation and dust collected in filters were obtained. PM10 seems to be correlated to the whole dust fraction that impairs visibility on gravel roads. A decay in PM10 concentration as a function of distance from the road was observed. Measured particles principally did not travel further than 45 m from the road. The risk of exceeding the PM10 concentration stated in the EC-directive seems small.

The measurement of soil erosion rates under natural rainfall conditions is costly and time consuming. Data provided by rainfall simulation and static site measurements can be used to predict erosion rates under natural conditions, however the accuracy of this method is largely untested. This is especially true for erosion rates from unsealed forest roads. In this study, the values for a range of erodibility indices calculated from rainfall simulation experiments are compared to observed erodibility index values from 1 year of detailed in-situ erosion monitoring of seven different forest road types. The prediction of phosphorus generation rates from rainfall simulation and/or soil sampling was also evaluated. The results showed that a series of commonly used erodibility indices such as sediment per unit rainfall, sediment per unit runoff, sediment per unit EI30, and sediment per unit rainfall energy were poorly predicted from the rainfall simulation experiments. Five of the six indices tested substantially overpredicted the observed erodibility at one site, a gravel road subjected to minimal traffic. For the other six road sites predictions were poor and highly variable, the coefficient of efficiency ranging from − 13.32 to 0.17 for these erodibility indices. A modified index, the ratio of sediment per unit rainfall energy to the mean rate of rainfall energy input, was able to predict annual erosion rates from six different road surfaces using rainfall simulation data with a coefficient of efficiency of 0.9. The results indicate that existing erodibility indices are not suitable for predicting observed erosion rates on forest roads using rainfall simulation data as collected in this study. It is argued that the modified index is more suited to sites (such as compacted roads) where interrill processes dominate, and erosion rates are less sensitive to peak flows. With respect to nutrient generation rates, rainfall simulation was able to accurately predict the observed proportion by mass of total phosphorus (TP) in runoff with a coefficient of efficiency of 0.96. Direct soil sampling of the road surface could also be used to predict the proportion by mass of TP in runoff. Concentrations of total nitrogen in forest road materials were found to be at the lower detection limit of the laboratory instruments.

Twenty gravel road study sections at 10 sites in north-central Wyoming were monitored from September 2005 through June 2006. Windshield or mobile, visual survey ratings of the sections and field measurements were taken weekly. Surfacing gravel samples were collected, and their gradations were determined. Traffic speeds and volumes by class were collected with a two-tube system. (A two-tube system counts traffic by receiving signals from two tubes placed 8 ft apart across the road. By a comparison of the times at which signals are received from each tube, the speed of the traffic can be determined, as can the number and spacing of axles.) Statistical analyses generated regression models that allowed the prediction of the service life of an unmaintained gravel road. Traffic speeds, traffic volumes, and surfacing gravel properties were shown to have the greatest influence on gravel roads’ deterioration rates. For these typical Wyoming county roads with good geometry, good drainage, and adequate gravel thicknesses, the typical failure mode was shown to be either potholes or washboards (corrugations). The typical life of gravel roads without maintenance was shown to be in the range of several months to 1 year. Climatic effects were shown to be related to precipitation more than seasonality, at least in Wyoming's dry–freeze climate.

Roads are a wide spread and increasing feature of most landscapes, have great ecological impacts, alter landscape spatial patterns and interrupt horizontal ecological flows strongly. Soil erosion is the dominating factor of damaging terrene roads in rural areas worldwide. Field tests for anti-erosion and maintenance techniques on terrene roads were conducted between 1996 and 2001 in Xiabiangou, Yan’an City in the Loess Hilly-Gully region of Shaanxi Province, China. The results of field tests showed that soil erosion on unpaved terrene roads with no vegetation was 3.09 times that of roads designed using special pavers sown with grass in the same situation. Roads sown with Bromus inermis , Elymus sibiricus , Elymus , Poa annua could bear traffic loads up to 300 vehicles year −1 . There were additional yields in benefits from fresh vegetable and seed production by B. inermis with strip sowing amounted to US$ 264.16 km −1 year −1 , while that for Coronilla varia and Lespedeza dahurica was between US$ 138.36 and US$ 205.52 km −1 year −1 , respectively. In order to avoid nutrient loss in the grass growth on the roads it is necessary to apply fertilizers to compensate for the decline in soil nutrients. The cost of grass road construction was 71.65% less than that of stone roads, with maintenance costs averaging 60.97% less than that of non-grass terrene roads. The results suggest that grass roads can fill the gap between paved and unpaved roads in areas with sloping terrain and low traffic volumes (rural countryside, nature reserves and parks) and thus minimize the level of soil erosion, landscape damage and other environment problems.

Runoff and sediment loss from forest roads were monitored for a two-year period in a Pinus plantation in southeast Queensland. Two classes of road were investigated: a gravelled road, which is used as a primary daily haulage route for the logging area, and an ungravelled road, which provides the main access route for individual logging compartments and is intensively used as a haulage route only during the harvest of these areas (approximately every 30 years). Both roads were subjected to routine traffic loads and maintenance during the study. Surface runoff in response to natural rainfall was measured and samples taken for the determination of sediment and nutrient (total nitrogen, total phosphorus, dissolved organic carbon and total iron) loads from each road. Results revealed that the mean runoff coefficient (runoff depth/rainfall depth) was consistently higher from the gravelled road plot with 0.57, as compared to the ungravelled road with 0.38. Total sediment loss over the two-year period was greatest from the gravelled road plot at 5.7 t km−1 compared to the ungravelled road plot with 3.9 t km−1. Suspended solids contributed 86% of the total sediment loss from the gravelled road, and 72% from the ungravelled road over the two years. Nitrogen loads from the two roads were both relatively constant throughout the study, and averaged 5.2 and 2.9 kg km−1 from the gravelled and ungravelled road, respectively. Mean annual phosphorus loads were 0.6 kg km−1 from the gravelled road and 0.2 kg km−1 from the ungravelled road. Organic carbon and total iron loads increased in the second year of the study, which was a much wetter year, and are thought to reflect the breakdown of organic matter in roadside drains and increased sediment generation, respectively. When road and drain maintenance (grading) was performed runoff and sediment loss were increased from both road types. Additionally, the breakdown of the gravel road base due to high traffic intensity during wet conditions resulted in the formation of deep (10 cm) ruts which increased erosion. The Water Erosion Prediction Project (WEPP):Road model was used to compare predicted to observed runoff and sediment loss from the two road classes investigated. For individual rainfall events, WEPP:Road predicted output showed strong agreement with observed values of runoff and sediment loss. WEPP:Road predictions for annual sediment loss from the entire forestry road network in the study area also showed reasonable agreement with the extrapolated observed values.

Testing Re-Entrained Kinetic Emissions from Roads (TRAKER) is a new technique to infer paved and unpaved road dust PM 10 emission potentials based on particulate matter (PM) measurements made onboard a moving vehicle. Light scattering instruments mounted in front and behind the vehicle's tires measure the differential particle concentration of dust suspended by the vehicle's tire in contact with the road surface. Through empirical regressions relating the differential concentration (i.e. TRAKER signal) with the vehicle speed and the downwind flux of PM 10 particles from the road, an equation is derived to infer the speed independent road dust emission potential from the measured TRAKER signal. Measurements from TRAKER offer a new perspective on the processes that affect road dust emissions. The system was used to investigate temporal changes in emission potentials from paved roads in both the winter and summer in the Treasure Valley in Southwest Idaho. During the 3-week wintertime sampling period, the residential road dust PM 10 emission potential decreased by ∼50%. Summertime PM 10 emission potentials were similar to those observed at the end of the winter sampling and showed no upward or downward trends. Wintertime unpaved road emissions increased consistently with the number of days since the last rainfall. Measurement of road dust emission potentials after road sanding on dry roads indicated a 75% increase in PM 10 emissions after 2.5 h. This effect was short lived and emission potentials returned to their pre-sanding levels within 8 h of the sand application. Street sweeping with mechanical and vacuum sweepers was found to offer no measurable reduction in PM 10 emission potentials. On several roads, the PM 10 emission potentials actually increased immediately after vacuum sweeping. Long term effects of street sweeping on road dust emissions were not evaluated as part of this study and may offer some overall reduction in PM emissions from paved roads.

The testing re-entrained aerosol kinetic emissions from roads (TRAKER) road dust measurement system was used to survey more than 400 km of paved roads in southwestern Idaho during 3-week sampling campaigns in winter and summer, 2001. Each data point, consisting of a 1-s measurement of particle light scattering sampled behind the front tire, was associated with a link (section of road) in the traffic demand model network for the Treasure Valley, ID. Each link was in turn associated with a number of characteristics including posted speed limit, vehicle kilometers traveled (vkt), road class (local/residential, collector, arterial, and interstate), county, and land use (urban vs. rural). Overall, the TRAKER-based emission factors based on location, setting, season, and speed spanned a narrow range from 3.6 to 8.0 g/vkt. Emission factors were higher in winter compared to summer, higher in urban areas compared to rural, and lower for roads with fast travel speeds compared to slower roads. The inherent covariance between traffic volume and traffic speed obscured the assessment of the effect of traffic volume on emission potentials. Distance-based emission factors expressed in grams per kilometer traveled (g/vkt) for roads with low travel speeds (∼11 m/s residential roads) compared to those with high travel speeds (∼25 m/s interstates) were higher (5.2 vs. 3.0 g/vkt in summer and 5.9 vs. 4.9 g/vkt in winter). However, emission potentials which characterize the amount of suspendable material on a road were substantially higher on roads with low travel speeds (0.71 vs. 0.13 g/vkt/(m/s) in summer and 0.78 vs. 0.21 g/vkt/(m/s) in winter). This suggested that while high speed roads are much cleaner (factor of 5.4 in summer), on a vehicle kilometer traveled basis, emissions from high and low speed roads are of the same order. Emission inventories based on the TRAKER method, silt loadings obtained during the field study, and US EPA's AP-42 default values of silt loading were compared. PM 10 paved road dust emission inventories calculated with the TRAKER method were 61% higher in winter and 180% higher in summer than inventories calculated from on-site silt loading measurements. Emissions calculated from silt loading measurements conducted on-site indicated that the AP-42 default values are too low for the Treasure Valley by a factor of 1.5 for summer conditions and by a factor of 3.8 for winter. Both silt loading and TRAKER are techniques that were calibrated against the horizontal flux of dust, which was estimated by the difference in PM 10 concentration between instruments located upwind and downwind of an unpaved road. The upwind/downwind method, and therefore both silt loading and TRAKER, gives a measure of the dust emitted near the source, and not the dust that can be transported on a regional or air shed scale. Correcting the measured dust emissions for deposition and removal near the source is outside the scope of this work, but is a continuing area of research among dispersion modelers.

Testing re-entrained aerosol kinetic emissions from roads (TRAKER) is a vehicle-based method for measuring road dust emissions. Particulate matter is sampled in front and behind a vehicle's tire and the difference in PM concentration is related to emissions. This paper describes the most recent developments of TRAKER. The loss of particles within the inlet lines, the response of the TRAKER signal (differential PM concentration) to vehicle speed, and the relationship between the TRAKER signal and unpaved road dust PM 10 emissions were examined. Losses of particles to the walls in the inlet lines were similar for the left and right inlets and were less than the inter-instrument precision for particles between 0.56 and 7.3 μm in diameter. When summed over the PM 10 size range, losses were less than 20%. Line losses were also characterized when a dilution system was used to sample emissions from unpaved roads. Two independent tests indicated that the TRAKER signal increases as the cube of the speed for a given road dust loading. Simultaneous measurement of PM 10 dust emitted behind the tires by TRAKER with PM 10 flux measured using upwind/downwind towers suggested that the emission factor for road dust was proportional to the cube root of the TRAKER signal. The results also showed a linear relationship between unpaved road dust PM 10 emissions and vehicle speed.

The U.S. Department of Agriculture Forest Service has stabilized unpaved road surfacing materials with relatively high concentrations of calcium chloride salt. The percentage of calcium chloride is higher than that traditionally used for dust abatement or aggregate base stabilization. Up to 2% pure salt by weight of aggregate was mixed into the top 2 in. (50 mm) of both aggregate and native road surfaces. The results were monitored for 2 to 4 years. The stabilized road surfaces resisted raveling and washboarding for several seasons and significantly reduced road blading and aggregate loss. As a result, calcium chloride stabilization may be a cost-effective treatment for roads with daily traffic volumes less than 200. Other benefits include reduced surface erosion and sedimentation; improved safety from reduced dust, raveling, and washboarding; and less frost penetration. Encouraged by these results, the Forest Service is conducting additional evaluations to determine the cost-effectiveness of surface stabilization with both magnesium chloride and calcium chloride in different environments and with different aggregate materials.

The Lithuanian state road network consists of more than 21,000 km of roads, and gravel roads dominate (43.3%). While the 1998–2000 Paving of Gravel Roads Program was being implemented, there were a few issues in estimating investments that could determine the implementation alternatives of the rehabilitation project. Total costs of renovated gravel roads depended on the climate and geological and hydrological conditions of a location as well as traffic and gravel road characteristics. Roads, like engineering buildings, have to be of sufficient strength and durability, and they should correspond to traffic volume. The results of tests showed diversity of pavements and the characteristics of renovated gravel roads. Gravel roads vary by road width, pavement structure, pavement materials, and traffic. In analyzing traffic on gravel roads, the roads were classified into four groups according to traffic volume. Frequently, the strength of subgrade soils determines the structure of renovated gravel roads. The authors carried out tests on road subgrades under different geomorphologic and geological conditions, estimating the structure, physical conditions, and mechanical properties of these subgrades. According to the test results the strength of existing gravel roads depends on the strength of the subgrade, the thickness of the gravel road, and the quality of the gravel. The equivalent deformation modulus of the gravel roads is described by a binomial. In selecting structures for reconstruction of gravel roads, mathematical models are suggested.

Recent restructuring of Canadian transportation has significantly increased commercial truck traffic on many rural roads in Saskatchewan, Canada. This increased traffic is having a detrimental effect on performance of the approximately 175,000 centerline kilometers of gravel roads collectively managed by provincial road agencies. The depletion of quality aggregate sources in many Saskatchewan regions is a primary contributor to the detrimental performance. Preservation and optimization of gravel are therefore becoming critical in sustaining an effective and efficient rural road system. Saskatchewan road agencies spend tens of millions of dollars per year purchasing gravel for the gravel road system. Even minor improvements in gravel optimization could significantly reduce the amount of gravel required for an acceptable level of service and save millions of dollars per year for taxpayers. A study was undertaken to quantify typical gravel supply and demand characteristics in Saskatchewan, the factors influencing gravel loss, and innovative means of gravel road preservation. Several rural municipalities were interviewed on their gravel road preservation practices and gravel supply and demand. Test sections were constructed to evaluate relationships between gravel loss and heavy truck loadings and to investigate innovative gravel preservation techniques. The study determined that most rural municipalities suffer from aggregate shortages. Gravel with a larger top size took longer to break down, and higher gravel application rates reduced gravel displacement. Ionic stabilization of gravel roads improved gravel retention and reduced dust, and shoulder reclamation with commercial rock rakes could recover gravel from roadside slopes for reapplication to the road surface.

The potential of cement kiln dust (CKD) and lime (quicklime) for stabilizing low-volume unpaved roads on sites dominated by cohesive soils was investigated. CKD, lime plus CKD, lime, and portland cement were tested at different mixtures and soil moisture contents in a clayey silt to determine the resulting unconfined compressive strength after three curing periods. In a field study, road sections were stabilized with CKD and with lime plus CKD, and then a gravel running surface was added. Soil penetration resistance increased after the treatment. Field results confirmed the laboratory results and helped identify the most effective treatment. Stabilization proved cost-effective for new roads in areas where gravel is difficult to obtain.

In Canada, over 300 heavy vehicles equipped with central tire inflation systems are being used in forestry, mining, and grain hauling. Since 1995, Saskatchewan Highways and Transportation has permitted truck fleets to operate with primary highway axle loads on secondary highways under a partnership program. This paper reports on the comparison of rutting progression on an accelerated field experiment utilizing standard and reduced tire pressures. The experiment was conducted by Saskatchewan Highways and Transportation in the Big Quill Lake area of southern Saskatchewan. The vehicles used in the experiment were nine-axle B trains, eight-axle B trains, and six-axle semi-trailers. The statistical analysis of rutting data presented in the paper shows that reduced tire pressures can effectively extend the pavement service life of gravel and thin membrane surfaced roads. On the thin membrane pavements, there was less rutting on the low-pressure lane until twice as many vehicles had trafficked the road, and rutting was no worse on the low-pressure lane even when 10 times as many vehicles had trafficked the road. On the gravel surface, rut depth was lower on the low-pressure lane until twice as many trucks had trafficked that lane.Key words: rutting, pavement, central tire inflation, tire pressure, low-volume roads, unsurfaced roads.

Roads in rural, upland landscapes are important sources of runoff and sediment to waterways. The downstream effects of these sources should be related to the connectivity of roads to receiving waters. Recent studies have explored this idea, but only simple metrics have been used to characterize connectivity and few studies have quantified the downstream effects of road–stream connectivity on sediment or solute budgets and channel morphology. In this study, we evaluated traditional and newly developed connectivity metrics that utilized features of landscape position and delivery pathway to characterize road–stream connectivity in upland settings. Using data on stream geomorphic conditions developed by the Vermont Agency of Natural Resources (Montpelier, VT), we related road connectivity metrics to channel condition on a set of 101 forested, upland streams with minimal development other than predominantly gravel road networks. Logistic regression indicated that measures of road density, proximity and orientation successfully distinguished among categories of stream geomorphic condition at multiple geographic scales. Discriminant function analysis using a set of inherent channel characteristics combined with road connectivity metrics derived at the reach corridor scale successfully distinguished channel condition for over 70% of the channels evaluated. This research contributes to efforts to evaluate the cumulative downstream effects of roads on stream channels and aquatic resources and provides a new means of watershed assessment to derive metrics that can be used to predict channel condition. Copyright © 2014 John Wiley & Sons, Ltd.

To develop a new specification of material for surfacing unpaved roads, an experiment was conducted on 41 unpaved road sections located in five different physiographical regions in the state of Rio Grande do Sul, Brazil. The behavior of the sections under observation was analyzed qualitatively to evaluate the performance of the applied surfacing material. Because the traditional soil classifications (Highway Research Board and Unified Soil Classification System) are not suitable for classifying tropical soils, a new classification, namely MCT (miniature, compacted, tropical), developed in Brazil in 1981 was adopted as a basis for material selection. The behavior parameters observed were support, frictional resistance, and durability. The results obtained led to the specifications presented here, which were tested during a doctorate research program developed between 1991 and 1996 conducted by the first author and supervised by the second. It was concluded that the proposed specification based on the MCT classification system is more adequate than the ones previously used based on traditional classifications. The “binder content” of soils, a measure similar to that used for bituminous materials (asphalt binder content) is introduced to evaluate the agglomerating capacity of the fine fraction and, therefore, the material durability.

Road cutslopes and fillslopes account for approximately 50 percent of the total road disturbance area on steep terrain and contribute as much as 60 percent of sediment from forest roads. The significance of erosion control techniques on these vulnerable components of the road prism has become evident in recent years. A study to gain a better understanding of erosion control techniques on road cutslopes and fillslopes is detailed. Sediment and runoff yield from three erosion control treatments and a control were investigated on west-facing 2:1 and 1.5:1 cutslopes and fillslopes, respectively, on a newly constructed road during a 30-month study. The treatments evaluated were a wood excelsior erosion mat, native species grass, and exotic species grass. Factors detected to significantly affect sediment yield from road sideslopes were treatment, time, and treatment-time interaction based on analysis of variance. Significant reductions in sediment yield and runoff were found on all treatments on both the cutslope and fillslope. The erosion mat most effectively controlled erosion losses on both slopes for all study periods.

The heat stability of embankment with different road surfaces on the permafrost regions containing rich moisture in the eastern Plateau at a rising speed of 0.04°C/a for the air temperature is modeled by numerical methods, and the critical heights of embankment were figured out by a regression analysis of the results, respectively for asphalt-paved, concrete and gravel road surfaces, according to the local natural geologic, geographic and meteorological conditions along the National Road 214. The modeled results are compared with that without climate warming, i.e. at a rising speed of 0.0°C/a for the air temperature. From the results, under the three types of road surfaces, the thermal stable critical heights are, respectively, 5.0 m actually not existing), 3.50 m, and 2.50 m for the rising speed of 0.04°C, and 4.50 m, 1.60 m, and 1.00 m without climate warming, there are obvious differences between two same road surfaces with and without climate warming. It is proved that the protection and cooling embankment measures on permafrost regions should be applied to lift the permafrost table under roadbed and insure the roadbed stability.

Vehicles traveling on dry, unpaved roads generate copious quantities fugitive dust that contributes to soil erosion, and potentially threatens human health and ecosystems. The purpose of this study was to develop a low-cost technique for monitoring road dust that would enable land managers to estimate soil loss. The "sticky-trap" collectors developed were evaluated at the Turkey Bay off-highway vehicle (OHV) riding area on the Land Between the Lakes National Recreation Area, in western Kentucky. The results showed that the dust plume created by vehicle traffic was heterogeneous: larger particles were in the lower part of the plume and deposited closer to the source, smaller particles were carried higher in the plume and traveled at least 100 m away from the source. Collection of particles parallel to the source was also heterogeneous, suggesting that measurements taken at a single point may not be appropriate for estimating erosion losses. Measurements taken along two trails indicate that when large numbers of riders are present, dust concentrations may reach unhealthful conditions for riders, but that it is unlikely that fugitive dust is harming native vegetation, given frequent rainfall. The study demonstrated that OHV traffic contributes to substantial erosion of roadbeds because of aeolian transport.

As a part of the Swedish mine detection project MOMS, an initial field trial was conducted at the Swedish EOD and Demining Centre (SWEDEC). The purpose was to collect data on surface-laid mines, UXO, submunitions, IED's, and background with a variety of optical sensors, for further use in the project. Three terrain types were covered: forest, gravel road, and an area which had recovered after total removal of all vegetation some years before. The sensors used in the field trial included UV, VIS, and NIR sensors as well as thermal, multi-spectral, and hyper-spectral sensors, 3-D laser radar and polarization sensors. Some of the sensors were mounted on an aerial work platform, while others were placed on tripods on the ground. This paper describes the field trial and the presents some initial results obtained from the subsequent analysis.

The thermal signatures of surface and buried land mines vary widely with time of day, weather, soil type, soil moisture content, and mine burial depth. There have been recent advances in modeling these effects, but until these models are fully developed and validated we will continue to rely on measured data. This paper witll present signatures in the medium-and long-wavelength infrared (MWIR and LWIR) spectral bands for surface and buried M19, M15 and VS1.6 anti-tank mines at two locations, a temperate site and an arid site. We will show that the apparent contrast of these landmines is substantial throughout the diurnal cycle except during thermal crossover periods after sunrise and sunset. Our results show that the mine signatures are well above sensor noise and that further improvements in sensitivity or resolution are not required. The paper will also present LWIR images of landmines buried in dirt and gravel road environments taken on a cold winter day and discuss the intriguing and unexpected differences observed between the images of landmines buried in dirt and gravel.

The Dalton Highway is a gravel road that was constructed in 1974 for transport of materials required in building the trans-Alaska pipeline. Presently, the road serves as a supply link between Fairbanks and the northern oil fields at Prudhoe Bay. The Dalton Highway is heavily traveled by large vehicles (we counted an average of 130 trucks per day during the summer of 1991). These vehicles generate large dust plumes in their wake (Fig. 15.1) particularly during periods of dry weather. This dust is deposited on the adjacent vegetation where it has detrimental effects on some arctic species (Everett 1980; Santelmann and Gorham 1988; Walker and Everett 1987; Auerbach 1992; see Chaps. 3, 9, 11, and 18, this Vol.).

The 93 km section of Highway 3 located between Behchoko (Rae-Edzo) and Yellowknife is located in an area with warm and discontinuous permafrost and variable ground ice contents. The highway was originally constructed as a gravel road in 1968. Between 1999 and 2006, the alignment for this section of highway was straightened and reconstructed, and the road surface chip-sealed. To date, this section of highway has experienced significant sagging in soil-covered areas and requires considerable maintenance efforts to keep the road in a comfortable and safe driving condition. Embankment deformations have been attributed to the degradation of the ice-rich permafrost foundation. The Public Infrastructure Engineering Vulnerability Committee (PIEVC), a national committee established by Engineers Canada, has developed a standardized protocol to assess the vulnerability of Canada's public infrastructure to climate change. The protocol continues to be tested on a variety of public infrastructures and in 2010, this section of highway was evaluated as a case study. More than 1100 highway infrastructure element - climate event combinations were assessed. Out of these combinations, five were identified as "high risk". The assessment identified those sections of the highway built on ice-rich permafrost as being at greatest risk, based on its low capacity to withstand the projected or anticipated climate-change related loads. Overall, the road embankment stability was found to be insensitive to climate change such that only functionality losses are expected, not sudden losses in capacity. Climate change will likely increase maintenance and repair efforts needed to maintain safe driving conditions.

In this study we examined the relative importances of soil factors, the presence of non-native grasses and the distance from seed sources of native species in explaining variation in natural revegetation among sixteen abandoned gravel pads in arctic Alaska