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On a local gravel road at Leppävirta, Central Finland (about 62° 27' N, 28° E), test pavements were constructed in the fall of 1996 to strengthen a gravel road, suffering from thaw damage. The improvement methods studied were bitumen stabilization in situ of the base layer, and a macadam overlay reinforced with a steel net. In the primary monitoring in 1997–98 it was fond that the improvement of the surface modulus was significantly higher at the reinforced pavement than a non-reinforced one. The estimated material modulus of the reinforced macadam layer (200mm thick) during thaw was 300–500 MPa. According to the FWD measurements in the spring of 2005, the back-calculated, equivalent material modulus of the reinforced layer during thaw had decreased to about a half of the value estimated after construction. The modulus in summer state was not observed to have significantly changed. In the test pit excavated across the road down to the reinforcement, and the leveling of the reinforcement it could be observed a bending (rutting) of the reinforcement. The estimated rut depth was 25 – 85 mm, and it was increasing with decreasing minimum thaw modulus of the gravel pavement. The rutting of the pavement was relatively low. Thus, it seems obvious that the reinforcement should be treated, not only applying as stiffening of the overlay, but also as an anchoring element, preventing the horizontal and shear stresses below.

On a local gravel road at Leppävirta, Central Finland (about 62° 27' N, 28° E), test pavements were constructed in the fall of 1996 to strengthen a gravel road, suffering from thaw damage. The improvement methods studied were bitumen stabilization in situ of the base layer, and a macadam overlay reinforced with a steel net. In the primary monitoring in 1997–98 it was fond that the improvement of the surface modulus was significantly higher at the reinforced pavement than a non-reinforced one. The estimated material modulus of the reinforced macadam layer (200mm thick) during thaw was 300–500 MPa. According to the FWD measurements in the spring of 2005, the back-calculated, equivalent material modulus of the reinforced layer during thaw had decreased to about a half of the value estimated after construction. The modulus in summer state was not observed to have significantly changed. In the test pit excavated across the road down to the reinforcement, and the leveling of the reinforcement it could be observed a bending (rutting) of the reinforcement. The estimated rut depth was 25 – 85 mm, and it was increasing with decreasing minimum thaw modulus of the gravel pavement. The rutting of the pavement was relatively low. Thus, it seems obvious that the reinforcement should be treated, not only applying as stiffening of the overlay, but also as an anchoring element, preventing the horizontal and shear stresses below.

The occurrence of fatalities on rural roads is twice or more than that on urban roads (National Highway Traffic Safety Administration, 2001). This brief article presents the findings of a paper given at the Traffic Records Forum in Buffalo, NY in 2005. The authors report on the Nebraska Crash Outcome Data Evaluation System (CODES) study undertaken to identify potential risk factors attributable to the increased crash fatality and injury rates on 50 mph roads. Crashes and crash victims were classified into three groups: crashes or people involved in crashes on the roadways with posted speed limits below 50mph, 50mph, and above 50mph. Crash proportions, fatality and injury rates, hospital charge, and odds ratio were compared among the three groups. The authors found that pronounced increases in crash injury and death rates were observed for crashes on 50mph roads. Only 8% of total crashes during 1999-2000 were on 50mph roads, but accounted for 22% of total fatal crashes and 9% of total injury crashes. The authors conclude that higher risks of deaths and serious injuries in crashes on 50mph roads were associated with teen driver involvement, low restraint use, alcohol involvement, single-vehicle fixed object, and rollover crashes as a result of speeding or driving too fast for conditions.

In the United States, the mileage of unpaved roads is about 1.6 million miles. Total length of unpaved roads in Kansas is about 98,000 miles, of which about 78,000 miles are gravel roads. Most of the gravel roads are not posted with speed limit signs but regulated with a 55 mph blanket speed limit established by the Kansas Statutes. Surface conditions of gravel roads are very likely to change with time, space, and quality of maintenance work, making it even more necessary to have proper control of speeds on gravel roads. Normally used speed regulations and rules for freeways or other types of paved roadways might not be appropriate for gravel roads, especially for those local gravel roads which usually carry very low traffic in rural areas. Based on an extensive literature search, there was no specific rule or references to provide guidelines on how speed limits on gravel roads could be set. Therefore, an effort was made in this study to evaluate the effects of currently posted lower speed limits in some counties in Kansas, based on traffic characteristics and safety on gravel roads, with the intention of providing proper guidelines for setting speed limits on gravel roads in Kansas. In order to study traffic characteristics on gravel roads, field speed studies were conducted with automatic traffic counters on more than forty gravel road sections in seven counties in Kansas. Important speed measures, such as 85th-percentile speed and mean speed, were obtained from the raw data. A group of other related road characteristics were also recorded at the time of field data collection. Crash data on gravel roads were extracted from the Kansas Accident Recording System (KARS) database. Speed analysis on a number of gravel roads where the statutory imposed, unposted speed limit of 55 mph was utilized indicated that they are functioning at a reasonably acceptable level in terms of actual speeds. In order to evaluate whether there were differences in traffic speeds between two counties or groups which have different speed limit settings on gravel roads, t-test was used. The analysis found that there was no significant difference between the mean speeds in two counties, one of which has 35 mph posted speed limit on gravel roads while the other does not post any speed limits. Moreover, the mean speed on the sections with 35 mph posted speed was a little higher than that on gravel roads without any speed limits. Linear models to predict 85th-percentile speed and mean speed on gravel roads were developed based on speed data. Both models indicated that traffic speeds are not significantly affected by the speed limit, but are related with 90% confidence to road width, surface classification and percentage of large vehicles in traffic. Chi-square tests were conducted with the crash data, and the results indicated that the posted 35 mph speed limit on gravel roads had not resulted in either smaller total number of crashes or decreased proportion of severe crashes, compared to gravel roads where no speed limits were posted. Logistic regression models were also developed on four levels of crash severity, which indicated that gravel roads with higher speed limits are likely to experience higher probability of having injury crashes. Two mail-back surveys were also conducted to gather the opinions of county engineers and road users on the subject of suitable speed limits on gravel roads. The majority of county engineers believed that blanket speed limit should be used for gravel roads and does not need to be posted. Three restrictions: changeful road conditions, unpractical law enforcement, and limited funds, are basic reasons why they do not think that gravel roads should be posted. Besides that, a few respondents said 55 mph is too high for gravel roads and needs to be lowered. Majority of the road users suggested that all gravel roads be posted with lower speed limit signs. However, they were more concerned about law enforcement since they believe that posted speeds won't bring any benefits if no law enforcement patrol gravel roads. Based on all aspects looked into in this study, it does not appear that reducing the speed limits and posting it with signs, is going to improve either traffic operational or safety characteristics on gravel roads in Kansas, and therefore is not recommended for new situations.

This article deals with the design problems of gravel road pavements. Mathematical models related to geological and hydrological conditions of a location, thickness of gravel pavement and characteristics of the gravel contained in this pavement are proposed to be used for pavements. For the selection of gravel pavements for reconstruction we recommend the models developed by the method of experimental planning to calculate the equivalent deformation modulus of the gravel pavements change depending on the deformation modulus of the subgrade, thickness of the gravel pavement and the materials used for its layers. Practical applications of these models will eliminate the mistakes that are still found in road pavement design. Frist Published Online: 30 Jul 2012

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.

NR 20140805

The city of Skagway, Alaska, responding to increasing visitor and tourist traffic, recently decided to improve access to the old abandoned ghost town of Dyea. Dyea is 15 km away over a narrow gravel road that winds around two deep fjords. Since the year-round-flowing Nelson Slough runs through the area, a bridge was needed to provide reliable access to Dyea Flats at all tidal stages. The city of Skagway received a grant from the U.S. Department of Agriculture Forest Service for assistance in design and construction of a timber bridge. The grant specified that the bridge must be constructed from untreated Alaska yellow cedar, a naturally decay-resistant wood species, using recently developed stressed-deck technology. The new bridge is simple. strong, aesthetic, and aromatic. The bridge is strong enough to handle any vehicle legally allowed on the road and should serve visitors to this historic area for many years to come.

This paper presents the work on the detection of land mines using IR-images. Experiments have been performed where outdoor time series of IR contrast have been measured for wax filled antitank mines in sand and for real mines in a gravel road. For antitank mines in the sand box the contrast dependence of time lap between burial and measurement has been analyzed for a period of four months. The diurnal contrast variation of an anti tank mine buried for two and a half year in a gravel road has been calculated. Statistical correlation between apparent temperatures and weather parameters for different cases have been calculated. The purpose is to understand the origin of the contrast and to be able to predict the contrast at different times and under different conditions.

During summer 1998 a series of tests were conducted in Finland in order to find out how Ground Penetrating Radar (GPR) technology can be utilized at both the project and network level, when surveying the wearing course thickness of gravel roads. The second objective was to investigate the possibilities of applying dielectricity information obtained using the GPR surface reflection method when determining the quality of the gravel road wearing course. In this study GPR was tested at the project level on highway 9241 Simo in Northern Finland, where the information provided by the GPR and laboratory research was used in designing and proportioning a new wearing course. In the network level studies, performed in the maintenance areas of Kemi and Karstula in Northern and Central Finland the goal for using GPR was to inspect the condition and thickness of the wearing course and evaluate the need for additional wearing course material. The total length of the roads under survey was approximately 200 km and both a 1.5 GHz ground-coupled antenna and a 1.0 GHz horn antenna were tested in this study. The research results show that GPR can be used to measure the thickness of the wearing course, the average measuring error against reference drilling measurements being 25 mm, which is considerably larger than the error of radar measurements in paved roads. To a great extent this is due to the fact that the thickness of the wearing course varies greatly even in the road's cross-section and thus a single reference thickness does not represent the actual thickness of the area measured with the GPR. The wearing course can often get mixed up with lower layers, which makes it difficult to determine the exact layer interfaces. For this reason reference information must always be used along with the GPR measurement results. Of the two GPR antennae tested, the horn antenna proved to be the more effective in measurements. The dielectric value of the wearing course, measured using the horn antenna surface reflection method, represents well the suction properties of the wearing course. High dielectric values reflect the water sensitive and frost susceptible wearing course materials where as low values reveal the lack of binder. A quality rating of the wearing course by its dielectrics and layer thickness is also suggested. In the measuring results analysis and presentations, GIS-maps proved to be invaluable.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A cost effective and robust automotive angular rate sensor (ARS) for rollover applications is still a challenge for sensor suppliers to develop and for rollover sensing system designers to evaluate. A test methodology is presented in this paper for evaluating an ARS used for detecting vehicle rollover. The key electrical parameters at specified temperatures are tested with a rate table. Immunity to linear accelerations is evaluated at room temperature with a vibration table and a thruster. The vibration test provides mechanical resonance information and rough road performance, while the thruster test provides g-sensitivity parameters under severe impact conditions such as with vehicle frontal and side impact events. The vehicle level evaluation includes severe vehicle maneuvers, rough road and gravel road tests, as well as full-scale vehicle rollover tests.

Grusvägarna omfattar en väsentlig del av det svenska vägnätet. Det statliga vägnätet omfattar 98 015 km väg varav 22 136 km (22%) är grusvägar (1997). Förutom de statliga grusvägarna finns även ca 35000 km enskilda grusvägar med statsbidrag och ca 210 000 km skogsbilvägar. Föreliggande litteraturstudie ingår som en första del i doktorandprojektet "”Effektiva produktionsmetoder inom drift och underhåll av grusvägar”". Denna rapport behandlar drift och underhåll av grusvägar huvudsakligen med inriktning mot grusslitlagret under barmarksperioden. I Sverige och de nordiska länderna infaller denna period normalt mellan maj och oktober. Med begreppet ”Drift och underhåll av grusvägar” menas i denna rapport all verksamhet som berör skötsel av grusvägar så att vägen hålls i farbart skick. Litteraturstudien består av tio kapitel vars rubriker finns i följande avsnitt: Kapitel 1 "Inledning", kapitel 2 "Grundläggande begrepp", kapitel 3 "Allmänt om vägnätet", kapitel 4 "Nedbrytning av grusvägar", kapitel 5 "Tekniska krav på grusvägar i Sverige", kapitel 6 "Faktorer som påverkar underhållet av grusvägar", kapitel 7 "Metoder för drift och underhåll av grusvägar", kapitel 8 "Tillståndsbedömning av grusvägar", kapitel 9 "Planering och värdering av drift- och underhålls-åtgärder", kapitel 10 "Referenser", Kapitel 11 "Figur- och tabellförteckning".

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.).

There are over one and a half million km of roads in Sub-Saharan Africa (SSA), including 554,000 km of main roads. Almost without exception, these roads are managed by bureaucratic government roads departments. The roads carry 80 to 90 percent of the region's passenger and freight traffic, absorb 5 to 10 percent of central government recurrent budgets and 10 to 20 percent of their development budgets. Furthermore, a significant proportion of the central government's disbursed and outstanding debt is attributable to road loans and the sector also absorbs a great deal of grant finance, mainly for procurement of construction and maintenance equipment. In terms of assets, employment and turnover (particularly with maintenance fully funded) roads are truly big business. They are generally far larger than railways, or national airlines. In spite of their importance, roads in SSA are poorly managed and badly maintained. The replacement cost of main roads in SSA is nearly $80 billion and it requires annual expenditures on routine and periodic maintenance of over $800 million to keep these roads in a stable long-term condition. African countries have spent nothing like this amount during the past 20 years and, as a result, about $14 billion of the capital invested in roads has been eroded through lack of maintenance. SSA has been living off its assets.

Publisher Summary This chapter presents a mathematical model to investigate the effect of vibrations on human body and vehicle due to rough roads. The chapter investigates the effect of three types of roads, namely, gravel road, paved road, and unpaved road. The problem has been analyzed under the scope of the linear vibration theory. The theoretical analysis performed on the model under consideration is based on a computer program using the transfer matrices method. The output variables obtained from the program are amplitudes, velocities, and accelerations resulting from impact force produced by road roughness. The previous parameters are computed for nine positions: the vehicle, hip, abdomen, diaphragm, thorax, torso, back, and head of the driver. The analysis is a step toward establishing international standards that allows a margin of safety for human exposure to vibration in passenger cars. The parametric analysis performed in this work also provides useful data to get better comfortability of the driver during vehicle motion on rough roads.

SUMMARY Presentation of 3 maps concerning the island of Romo: Plate 1: The landscape elements (ecotypes). Plate 2: The man-made constructions as settlements, roads, dam, dikes and a harbour as well as plantations. Plate 3: A land use map supplemented by noise zoning of road traffic, an interference leaving a minor part of the area as being untouched nature. Plate 1: 1) Tidal flats, low lying, 2) Creek, 3) Channel, 4) Tidal inlet, 5) Tidal flat, sandy, 6) High sand, 7) Sandy salt marsh, 8) beach ridge, 9) Break-through of the sea, 10) Deflation plain, 11) Dunes, minor forms, 12) Dunes, greater forms, 13) Salt marsh of the foreland, 14) Muddy tidal flats, 15) Phragmites salt marsh, 16) Agricultural area, 17) Polder area, 18) Marine foreland, dike burst. Plate 2: 1) Macadam main road, 2) Macadam road, 3) Gravel road, 4) Earth road, 5) Sand road, 6) Dike, 7) Line of poles, 8) Settlements, 9) Recreational area, 10) Camping, 11) Plantations. Plate 3: 12) Agricultural area, diked in, 13) Agricultural area, undik...

Effects of potential barriers (roads and cultivated fields) on both demographic and genetic features of subpopulations of white-footed mice were studied near Ottawa, Canada. Live trapping, colored bait and track registry were used to study animal movements across roads on four 1.44 ha areas each within a small forest bisected by a narrow gravel road. The genetic study was done in 11 other forest fragments separated from each other by cultivated fields. Frequencies of three electrophoretic variants of salivary amylases were established for mice caught in each patch of wood and genetic similarity of subpopulations was calculated. Movements of mice across the roads were very infrequent (quantitative barrier), although movements adjacent to roads were frequent and long enough to cross the roads. Salivary amylase data showed that studied subpopulations were genetically very similar although the sample was intentionally biased toward demographic isolation. Results are discussed in terms of possible hierarchical relationships of metapopulations and genetic demes in the context of landscape ecology, management and conservation practice.

The paper considers the dynamics of a vehicle running over a developing corrugation on an earth or gravel road. Theoretical models are used to show that the maximum contact force is imposed on or near the corrugation crest. Full-scale rolling rig experiments confirm this. Field observations show that the great majority of vehicles travel over corrugations at speeds that are above both the sprung and unsprung resonances. Hypotheses of road corrugation are discussed in the light of the results.

CAN ONE PROMOTE the professionalization of a field while preserving respect for its amateurs? In history, unlike medicine or the law, I think it may be not only possible but necessary. The care and use of historic resources in many communities will be dependent on volunteer enthusiasm for a long time to come, even when professionally guided. Certainly the much-needed development of truly effective formal training programs for work in history beyond the campus and the classroom need not engender contempt for those people who already are succeeding out there. Indeed, as part of their training, future history professionals need to know about working with volunteer historical groups. They need to know, I'd like to suggest in this (I hope not too fancifiul) essay, about the likes of Lester. I first met Lester a couple of years ago when I got an invitation from the Old Hickory Historical Society down in Hickory County, Tennessee. They asked me to come give a speech on the subject: "Hard Times for History: Is There Hope?" The day before the invitation, the blasting and bulldozing had started for a new leg of the Interstate through Nashville, where the American Association for State and Local History (AASLH, which I direct) is headquartered. It was near enough our offices for the field mice to seek refuge with us. It infuriated me anyway because of the old neighborhoods it was displacing. And also the noise made it hard for the staff to work. I accepted the invitation from Hickory County and slipped out of town. I drove down toward Chattanooga on a stretch of completed Interstate. I took a left on a gravel county road as I had been instructed. I found the place where the gravel road forks off to become the main street of the seat of Hickory County. And there I located the fire hall where the meeting was to be held.

High winds at a maximum speed of 96 mph (43 m/s) hit the Columbia Regional Airport in Missouri on June 17, 1985, causing heavy damage to parked aircraft, hangars, building glass windows, automobiles, and so on. A post‐disaster investigation reveals a wealth of information, such as the finding that the storm was a microburst, and not a tornado as it was originally classified, that the aircraft tiedown system was flawed, that a gravel road was the principal source of damage to cars parked at the airport terminal, that the gust factor of this type of wind is much higher than normally assumed for structural design, and so on. Additional findings are that the atmospheric pressure of the storm measured was greatly affected by the wind‐generated pressure of the building in which the barometer was housed, and that west is the predominant direction of high winds at this airport. Lessons learned from the investigation can be very helpful in reducing future wind damage at airports and in improving understanding of w...

Introduction In the early evening of 28 December 1974, a magnitude 6.0 ( m b USGS) earthquake occurred in a remote and mountainous region of northern Pakistan, resulting in loss of life and damage to property. The Pakistani Army Engineers involved in construction and maintenance of the Kara Korum Highway, a one-to two-lane gravel road along the Indus River valley, quickly established an efficient relief operation. Since the highway was damaged and unusable during most of the relief operation, helicopters were used to carry supplies from Besham, at the end of the usable highway, to Pattan, where a hospital camp was set up. Two seismic reconnaissance teams visited the affected area: the first arrived from Tarbela Dam on 1 January 1975, and included one of the authors (Pennington); the second team, with the other three authors (Ambraseys, Lensen and Moinfar) arrived later in January. The following report is based largely on their field studies (Ambraseys et al . 1975; Pennington 1975). The earliest known earthquakes of the Northwest Frontier Provinces (NWFP) As early as the 4th century BC, the region north of the Jhelum was reputed for its destructive earthquakes. Historians who accompanied Alexander the Great on his expedition in Swat allude to such events; they briefly state that as a result of earthquakes in this track of country even the beds of rivers are changed. Alexander must have reached Aornos (modern Pir-sar about 20 km from Besham) late in 327 BC (Stein 1927, 1929; Fig. 3).

IN the first light of morning our truck rattled along the gravel road, stones as big as cantaloupes beating a tattoo against it. I craned my neck to take in every aspect of the unfamiliar landscape. A gray mist veiling the tobacco fields partially obscured the distant hills. Now and then, a blanket-wrapped figure on horseback loomed up out of the mist with only his eyes showing under a widebrimmed sombrero. This was very different from a trip to my former office with the Health Department in New York City. Scarcely a month before, I had not even heard of the state of Nayarit in Mexico, let alone a village called Paredones, which we were now approaching. But I had heard that the American Friends Service Committee, a Quaker organization, was looking for volunteers to assist in a Mexican pilot project. The program was government-sponsored and set up according to United Nations Educational, Scientific and Cultural Organization policies. Its aim was to give technical assistance and basic educational guidance, and public health nursing was inherent in it. Here was an educational experience not to be missed. After working in a big city health department, I thought, it would be fascinating to observe a small-scale public health program in another country. I filed applications with the American Friends Service Committee to serve for a period of four months as a public health nurse. And here I was on my way to where the project was underway.