Snow Pile Research Articles

Survey of Practice and Literature Review on Municipal Road Winter Maintenance in Canada

AbstractEfficiency of winter operations is essential for cities in cold regions because fiscal budgets are limited and excessive amounts of street sand and salt can negatively impact the environment. A review of winter maintenance policies in major Canadian cities has shown that freeways, business areas, and routes to transit and emergency venues are treated as priority. On these routes, snow is piled on the roadsides until it narrows the road width and decreases drivers’ visibility. At such time, the snow piles are hauled to specific snow storage or eliminator locations. In cities with relatively warmer climatic conditions, such as Ottawa, Toronto, and Montreal, high amounts of street salt are used annually. In cities with extremely cold winters, such as Edmonton, Calgary, and Winnipeg, Canada, sanding is more common. Friction measurement devices, which have been developed in a number of diverse models, can provide data to compare and improve winter maintenance operations. Road friction measuring devices...

Direction based Hazard Routing Protocol (DHRP) for disseminating road hazard information using road side infrastructures in VANETs.

This paper presents Direction based Hazard Routing Protocol (DHRP) for disseminating information about fixed road hazards such as road blocks, tree fall, boulders on road, snow pile up, landslide, road maintenance work and other obstacles to the vehicles approaching the hazardous location. The proposed work focuses on dissemination of hazard messages on highways with sparse traffic. The vehicle coming across the hazard would report the presence of the hazard. It is proposed to use Road Side fixed infrastructure Units for reliable and timely delivery of hazard messages to vehicles. The vehicles can then take appropriate safety action to avoid the hazardous location. The proposed protocol has been implemented and tested using SUMO simulator to generate road traffic and NS 2.33 network simulator to analyze the performance of DHRP. The performance of the proposed protocol was also compared with simple flooding protocol and the results are presented.

Laser-filament-induced snow formation in a subsaturated zone in a cloud chamber: Experimental and theoretical study

1 kHz, 2 mJ, 45 fs, 800 nm laser pulses were fired into a laboratory diffusion cloud chamber through a subsaturated zone (relative humidity ∼73%, T ∼ 4.3 °C). After 60 min of laser irradiation, an oval-shaped snow pile was observed right below the filament center and weighed ∼12.0 mg. The air current velocity at the edge of the vortices was estimated to be ∼16.5 cm/s. Scattering scenes recorded from the side show that filament-induced turbulence were formed inside the cloud chamber with two vortices below the filament. Two-dimensional simulations of the air flow motion in two cross sections of the cloud chamber confirm that the turbulent vortices exist below the filament. Based upon this simulation, we deduce that the vortices indeed have a three-dimensional elliptical shape. Hence, we propose that inside vortices where the humidity was supersaturated or saturated the condensation nuclei, namely, HNO(3), N(2)(+), O(2)(+) and other aerosols and impurities, were activated and grew in size. Large-sized particles would eventually be spun out along the fast moving direction towards the cold plate and formed an oval-shaped snow pile at the end.

Measuring vehicle impacts on snow roads

The snow roads at McMurdo Station are the primary transport corridors to move personnel and material from the airfields servicing intra- and inter-continental air traffic for resupply. Thus, they are a critical transportation component and are particularly susceptible to deterioration during the warmest parts of the austral summer when above-freezing temperatures can occur for several days at a time. This study served to explore methodology that could quantify the impact of various vehicles, tires, driving speeds and maneuvers on the snow road conditions. Basic maneuvers were used to isolate the impact of turning, acceleration, braking and speed using spirals, circles, and straight-line testing on a flat, smooth snow pavement. In addition, a road course was set up to include corners and roughness using portions of the active snow roads for more realistic conditions. Measurements included snow surface strength both in and between tire tracks, tire track rut depth and width, and the height and width of the resulting snow piles adjacent to the tire tracks. Results indicate the impacts of driving speed and vehicle type including the importance of the tire and suspension components for preserving the road surfaces through the melt season. Since this type of testing had not been done on snow before, or using these vehicle types, the experiments yielded valuable guidance regarding what types of maneuvers, test surfaces, and measurements could most easily differentiate performance.

Quantification of Hydrocarbon Contaminants in Meltwater and Sediment in a City Snow Pile

AbstractSnow collected from roadways in northern climates is not pristine and may contain sand or gravel, deicing agents, litter, and airborne pollutants. Although fate and transport of contaminants in snowmelt has been studied under laboratory conditions, it is unknown whether the same mechanisms apply to a heterogeneous snow pile. This case study sought to identify and quantify organic species in snow pile meltwater in Edmonton, Canada, and estimate the total potential hydrocarbon loading bound to sediment. Analysis of meltwater and sediment samples revealed that most hydrocarbons were present in sediments, with meltwater containing low concentrations ( C10–C16) and F3 (>C16–C34) fraction hydrocarbons. Sediments showed detectable levels of F2 and F3 hydrocarbons in ∼21% of the samples tested, with concentrations ranging from approximately 600 to 7,800 mg·kg−1, with average F3 concentrations (the main source of hydrocarbons) well below Canadian guidelines for most samples. The estimat...

SNOW ACCUMULATION AT HOUSES AND BETWEEN BLOCKS OF RESIDENTIAL AREAS

Field survey and aerial photo analysis were used to clarify the characteristics of snow accumulation between the blocks of a newly built residential area in Takasu Town, Hokkaido. Factors affecting snow accumulation were analyzed, and the findings are summarized as follows.The pattern of snow accumulation around each house depends largely on the snow and wind conditions created by the house(s) and other buildings nearby. When houses with different roof shapes are built side by side, snow falling from the roofs cause complicated snow pile problems. Snow drifts in such residential blocks are the result of complicated wind flow that results from the presence of houses and other buildings. When planning the construction of a housing in a residential area in a snowy region, it is desirable to take into consideration not only the naturally falling snow but also the influence of snow accumulation on existing houses, including the accumulation in snow drifts and snow piles that will result from the planned house.

138. Utilization of snow piles removed from streets in downtown for cooling brown rice storehouse

138. Utilization of snow piles removed from streets in downtown for cooling brown rice storehouse

Practical Melting Forecasting of Artificial Snow Made from Treated Wastewater

Making snow from treated municipal wastewater is an interesting polishing treatment for wastewaters in cold climate. A study was conducted of the behavior of an artificial snow pile made from treated wastewaters. This kind of snow differs from natural snow characteristic of rural areas in structure, density, and amount of impurities. The simple degree-day model was found suitable for modeling the melting of the snow; it is easy to use and gives results useful for practical forecasting.

Snow Characterization at a City Snow Storage Facility

A field investigation involving snow coring, surveying, and melt water collection was undertaken at a city snow storage facility to characterize the snow and melt water in Edmonton, Alberta, Canada. The investigation revealed a high content of both salts and sediment within the snow, a pile volume of 500,000 m3 , a snow density of 0.63–0.83 g/ cm3 , and an average road salt content of 1.2 g/L within the melted snow. The salt within the Poundmaker snow pile, one of Edmonton’s five snow storage sites, represented approximately 1.5–2.0% of the total amount of salt that was used on the city roads during the 2006/2007 winter. Melt water fractionation took place on-site during the spring melt and salt concentrations in the March melt water (early spring) were often more than 10 times the concentration of the bulk snow. Some of the factors affecting the snow and melt water composition included the snow retention time on streets, snow source, weather/climate, sampling technique, and snow site characteristics/ope...

Release of Impurities from Melting Snow Made from Treated Municipal Wastewater

To make snow from treated municipal wastewater is one possible polishing treatment method that can be used in cold climates. In this study, the behavior of an artificial snow pile made from treated wastewater was studied. The primary focus of the study was the release of residual contaminants into the meltwaters. It was found that the first meltwaters of the snow pack are the most concentrated with contaminants. The first 30% of the meltwaters from the snow storage area included 50% of all the impurities held in the snow pack.

Potential for localized groundwater contamination in a porous pavement parking lot setting in Rhode Island

The control of polluted surface runoff and the assessment of possible impacts on groundwater is a concern at the local and regional scale. On this background, a study investigates possible impacts of organic and inorganic pollutants (including bacteria) originating from a permeable asphalt parking lot on the water quality immediately beneath it. The functioning of the permeable pavement, including clogging and restricted vertical percolation, was also evaluated. Four nested sample ports (shallow and deep) were installed below low- and high-traffic areas, including one port outside the parking lot. At least initially there was a good hydraulic connection between the parking surface and the shallow sample ports. The presence of a geotextile layer at the base of the parking lot structure, however, was identified in lab tests as one factor restricting vertical percolation to the deeper ports. Clogging of the permeable surface was most pronounced in heavy traffic areas and below snow pile storage areas. Corroborated by high electric conductivity and chloride measurements, sand brought in by cars during winter was the principal cause for clogging. No bacteria or BOD were found in percolating water. Polycyclic aromatic hydrocarbons (PAH) were present at concentrations near minimum detection limit. Nutrients (nitrate and phosphate) were being leached into the ground via the permeable parking lot surface at annual flux rates of 0.45–0.84 g/m2/year. A multi-species tracer test demonstrated a retention capacity of the permeable parking lot structure of >90% for metals and 27% for nutrients, respectively.

Road Salt Influence on Pollutant Releases from Melting Urban Snow

Abstract A snow-melting experiment was performed to study the effects of road salt on the melting of urban snow from a snow windrow (pile) along a road in central Luleå, Sweden. Two snow piles were formed in the laboratory, with and without road salt added, and melted under similar conditions. All meltwater was collected and analyzed. The purpose of the experiment was to study the influence of the use of de-icing salt on meltwater quality and the release of pollutants from urban snow. The study indicated that the use of road salt may increase the dissolved metal phase in the urban snow meltwater. Also, the salt seems to have the largest effect at the beginning of the melting period when chloride is leaving the snow pile. Of total chloride, 90% was transported with the first 20% of the meltwater. Concentrations of the particulate-bound metals showed a fairly constant rate of release at the start of melt, but increased rapidly towards the end of the melting period, and this was more pronounced in the case of snow containing high chloride concentrations. Overall, a larger transport of solids was found for the pile with salt due to faster melting. Significantly larger masses of suspended solids and two heavy metals (Cu and Zn) were released with the meltwater from the pile with salt in comparison with the no-salt pile. The rest of the suspended solids and heavy metals stayed in the solid residue remaining at the end of the experiment.

Observations of urban snow properties in Calgary, Canada

AbstractUrban winter hydrology has garnered very little attention owing to the general notion that high‐intensity rainfalls are the major flood‐generating events in urban areas. As a result, few efforts have been made to research urban snow and its melt characteristics. This study investigates the characteristics of urban snow that differentiate it from rural snow, and makes recommendations for incorporating these characteristics into an urban snowmelt model. A field study was conducted from the fall of 2001 to the spring of 2002 in the city of Calgary, Canada. Snow depths and densities, soil moisture, soil temperature, snow albedo, net radiation, snow evaporation, and surface temperature were measured at several locations throughout the winter period. The combination of urban snow removal practices and the physical elements that exist in urban areas were found to influence the energy balance of the snowpack profoundly. Shortwave radiation was found to be the main source of energy for urban snow; as a consequence, the albedo of urban snow is a very important factor in urban snowmelt modelling. General observations lead to the classification of snow as one of four types: snow piles, snow on road shoulders, snow on sidewalk edges, and snow in open areas. This resulted in the development of four separate functions for the changing snow albedo values. A study of the frozen ground conditions revealed that antecedent soil moisture conditions had very little impact on frozen ground, and thus frozen ground very nearly always acts as a near impervious area. Improved flood forecasting for urban catchments in cold regions can only be achieved with accurate modelling of urban winter runoff that involves the energy balance method, incorporating snow redistribution and urban snow‐cover characteristics, and using small time steps. Copyright © 2004 John Wiley & Sons, Ltd.

Effect of Frost Heaving on the Failure of Deep Structures

frost. At the outset of the 1950s, a small single-story commercial brick building was constructed in th e northern suburbs of Moscow. This building was in normal service until the beginning of the 1990s. It wa s then preserved. In 1997, a 24-m long and 7-m wide area, which was oriented from east to west with respec t to length, was graded in front of the facade. The area abuts a 6-m-wide highway carrying rather heavy traffic . A shallow sand-gravel cover layer was placed on the surface of the site. Snow was carefully removed from the area from the outset of the winter of 1997-1998, and stored o n its western side. In mid-December 1998, a water line running parallel to the highway failed beneath the site . This suggests that deep freezing of the soils in the roadway bed is frequently responsible for the failure o f water-supply lines near these roads. A cast-iron water-supply pipe 250 mm in diameter was placed at a depth of 2.5 m in morainic claye y loams. The water table is located at a depth of 18 m. Rupture of the pipe occurred at a distance of 5 m to th e east of the snow pile. As in the previous year, snow was removed from the site from the outset of the winter of 1998-1999 , and in March 1999, a second failure of the pipeline was observed at a distance 6 m to the east of the prev i ous year’s failure. A third failure of the water line beneath this site was observed at the beginning of Febr u ary 2000. Nonuniform heaving of cohesive soils, which results in the failure of highway pavement, is one of th e most dangerous forms of deformations of an earth roadbed in regions with seasonal frost and unfavorable we t ting conditions . The number of these emergency situations has recently increased considerably in the towns and vi l

Snow heterogeneity in Luleå, Sweden

Snow water equivalent (SWE) and snow covered area (SCA) are fundamental considerations when planning for snowmelt events. Depth, density and albedo measurements are used to demonstrate the spatial variability of SWE in the city of Luleå, Sweden. Undisturbed urban snow is similar to nearby rural snow (albedo 0.5–0.6, density 200–300 kg m−3) whereas ploughed snow piles have a wide range of characteristics (albedo<0.3–0.5, density 250–700 kg m−3). Snow piles are located on permeable surfaces in suburbs and impervious surfaces where landuse is intense. Snowmelt runoff simulated assuming first a homogenous then a heterogeneous snowpack shows that the presence of piles can reduce the maximum volume of melt and extend the melt period.

Status and biology of Saimaa (&lt;i&gt;Phoca hispida saimensis&lt;/i&gt;) and Ladoga (&lt;i&gt;Phoca hispida ladogensis&lt;/i&gt;) ringed seals

Saimaa (Phoca hispida saimensis) and Ladoga (P. h. ladogensis) seals are subspecies of ringed seals that live in freshwater lakes. The founding populations for these two subspecies became separated from Arctic ringed seals (P. h. hispida) during the last ice age. The Saimaa seal population currently numbers approximately 200 seals with 36 - 40 pups born annually. The Ladoga seal population contains at least 5,000 seals. The weight of adult animals in Lake Saimaa is 45-100 kg (mean 62 kg) and in Lake Ladoga adults weigh 32-56 kg (mean 47 kg). The lanugo of Saimaa seals is grey. Normally pups in Lake Ladoga are born with white lanugo, although some pups have been found that have black hairs in the natal pelt. Adult Saimaa seal vary a lot in colour, ranging from dark to pale animals, but all colour morphs have regular ringed patterns on the pelt. Ladoga seals are usually quite dark, with irregular, light ringed patterns. Saimaa seals are usually found hauledout alone or in pairs along shorelines. Ladoga seals haul out in herds of up to 300 animals, and are very vocal when they are hauled out. The lairs of Saimaa seals are situated in snowdrifts adjacent to shorelines of islets, which are the only places where snow piles up in Lake Saimaa. Most Ladoga seal lairs are situated near hummocked or ridged ice along the shoreline of the lake, but some lairs are also found along the shorelines of islets in northern Lake Ladoga. Saimaa seals are an endangered population. The main threats to these seals are fisheries conducted using nets and destruction of breeding habitat. The Ladoga seal is vulnerable, and it also is threatened by fishing. Mercury in both lakes presents an anthropogenic risk factor, but present levels probably do not affect the breeding of either seal population.

Absorbability of Ammonia Gas from Room Air by Snow Cooling System.

Snow has been already used effectively as the coolant for refrigerator in some heavy snowfall area in Japan. As the surface of snow is covered with cold melting water, we can expect the gas absorption on the surface. By this mechanism, the snow is able to remove some contaminants from air such as dust or harmful gases. As in the snow cooling system, air is cooled directly by the surface of vertical snow hole drilled through snow pile, some contaminants are removed automatically and simultaneously with heat transfer process. The heat and mass transfer process are very complicated because the surface area of snow decreases and the shape of snow changes in accordance with its melting process. In this study, the authors measured the absorbability of ammonia gas as the example of contaminant of room air with a pilot plant of the snow cooling system. Experimental results show that the mass transfer rate of ammonia through the melting snow surface is depndent on air flow rate and ammonia concentration, but is not dependent on the volume of snow remaining. And it is cleared that this filter effect of the snow surface can be applied to actual use of contamination control of air conditioning.

Survey of Snow Pile on Sidewalk and Consideration of Security for Pedestrian Area

In this paper, the method of survey of snow pile on sidewalk and the result in winter of 1994 in Fukui city are reported. In this winter, the maximum depth of snow was 66 cm high and it was less than normal value 76 cm. But there is a small study on security for pedestrian in snow season, so this paper must be very usefull.After snowfall, usually it is found that snow piles are formed on roadside or sidewalk by snow removal from roadway. Sometimes mass of snow is carried there from parking area or front of house.At first, the model of calculation of snow piling on sidewalk by removal work is presented and we discuss how pedestrian area to be kept secure. The state of pedestrian area is classfied into three levels by means of appearance of snow pile. Especially it is important for planning of snow melting facility or snow removal work on sidewalk to make clear how each level go on untill snow melt away.We made surveies of two places of prefectural road in Fukui city, and snow pile was divided into seven types by means of piling progress. In one area of Fukui city, we investigated relations between security for pedestrian and appearance of snow pile. And it was confirmed that snow pile had affected influence on pedestrian more long time than natural snow cover.

Emission from an inhomogeneous layer with irregular interfaces

A theoretical model for microwave emission from an inhomogeneous layer has been developed using the radiative transfer method. The top and bottom boundaries of the layer are assumed to be randomly rough surfaces, and the scatter characteristics are assumed to be describable by the Kirchhoff scatter model. The presence of an irregular top boundary is found to cause a slower angular trend than the case of a plane layer and causes, in addition, a rise in temperature if the layer permittivity is large. On the other hand, if only the bottom boundary of the layer is rough, a rise in emission is observed relative to the plane layer. When both the top and the bottom boundaries are rough, the emissions at small nadir angles are closer to those of a layer with a rough bottom boundary, and the emissions at large nadir angles are closer to those of a layer with a rough top boundary. A comparison of the layer model with reported angular measurements from a snow layer at three different frequencies and polarizations shows promise for such a model. An additional comparison of emission versus the depth of a snow pile indicates that an irregular snow ground interface causes higher emissions at small depths. This fact is necessary to explain the observed measurements.

Drag of Bodies Moving through Snow with High Speeds

Drag of bodies moving through snow with high speeds (1540m/sec) was studied. Shells (as. high-speed moving bodies) were shot into snow pile by an air gun, and output in s built-in acceleration meter was recorded on oscillogram. The impulsive acceleration of shells was measured when they hit the snow surface, and the relation between the drag and the speed of the shell was obtained by integrating the curve on the oscillogram. In the speed range studied, the drag of a body can be expressed as a sum of a term proportional to the square of the velocity and a constant term.