Use of Snow Fences to Reduce the Impacts of Snowdrifts on Highways: Renewed Perspective

2017 ◽  
Vol 2613 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Sen Du ◽  
John Petrie ◽  
Xianming Shi
Keyword(s):  
Road Safety ◽  
Right Of Way ◽  
Drifting Snow ◽  
Snow Fence ◽  
Survey Results ◽  
Snow Fences ◽  
The Right ◽  
Survey Responses ◽  
Almost All ◽  
Departments Of Transportation

In northern climates, snow fences are usually established in or beyond the right-of-way to eliminate blowing and drifting snow on roadways and thus improve road safety. To make snow fences more effective on highways and provide guidelines for the departments of transportation siting the fences, this work reviews the literature as well as survey responses from practitioners in northern states. This review combines information obtained from the resources to detail several aspects of snow fence use, including history, design protocols, siting policies, benefits, challenges, and numerical modeling. Particular attention is paid to living snow fences as an alternative to traditional structural snow fences. The survey results show that almost all the responding agencies have launched snow fence programs, which have various design and siting protocols that depend on the specific conditions.

scholarly journals Field experiments on “living” snow fences

1998 ◽  
Vol 26 ◽  
pp. 217-220 ◽  
Author(s):  
Florence Naaim-Bouvet ◽  
Pierre Mullenbach
Keyword(s):  
Field Experiments ◽  
Snow Accumulation ◽  
Real Problem ◽  
Effective Height ◽  
Natural Plant ◽  
Drifting Snow ◽  
Snow Fence ◽  
Limited Scale ◽  
Living Fences ◽  
Snow Fences

In Franee, drifting snow is generally controlled using artificial snow fences. Living snow fences are not a new concept but they have only been used on a limited scale. Research directly related to natural plant barriers is limited. We therefore decided to study the behaviour of species that would survive and grow satisfactorily in the French Alps.In the first experiment, we compared the storage capacity of several different kinds of living fences consisting of pruned spruces, unpruned spruces and sorbs.Field observations during the winter of 1995-96 proved that deciduous trees such as sorbs are effective, and that pruning the lower 50 cm is not effective at the end of the season because of the weight of snow on low branches.However, the use of natural plant barriers has disadvantages: a living snow fence takes time to reach an effective height and is difficult to establish on windy sites at a high altitude. This is a real problem. Therefore, in a second experiment, we studied the death rate of larches planted behind a fence. We noticed that the snow fence had several effects, snow accumulation (until the planted trees grew up) and protection of the planted trees.

scholarly journals Design Criteria and Location of Snow Fences

1985 ◽  
Vol 6 ◽  
pp. 68-70
Author(s):  
Harald Norem
Keyword(s):  
Minimum Distance ◽  
Storage Capacity ◽  
Windward Side ◽  
Design Criteria ◽  
Total Density ◽  
Design Considerations ◽  
Drifting Snow ◽  
Snow Fence ◽  
Snow Model ◽  
Snow Fences

The paper describes experience gained in Norway regarding the design criteria and use in practice of snow fences. The paper is based on theoretical studies on drifting snow, model experiments and experience accumulated through practical consulting work.Snow fence design is a compromise between the storage capacity and minimization of dimensioning forces. Design considerations include fence height H, total snow fence density, and the gap between ground and fence. A gap of 0.15H - 0.2H and a total density of 45% are usually recommended. On ridge crests the gap can be reduced to 0.1H and in areas where snow depths exceed 2.0 m, it can be increased to 0.3H. In such cases the fence density should be varied such that the total density, including the gap, will remain near 45%. The height of the snow fences should be kept within 3.5 -4.5 m and the snow fences should be erected on the windward side of obstacles that create snowdrifts. The minimum distance from fence to road should not be less than 15H; in certain circumstances in coastal climate, this can be reduced to 10H.

Exceptions to Mutual Trust: Children's Use of Second-Order Beliefs in Responsibility Attribution

1987 ◽  
Vol 10 (2) ◽  
pp. 207-223 ◽  
Author(s):  
Nicola Yuill ◽  
Josef Perner
Keyword(s):  
Second Order ◽  
The Other ◽  
Cooperative Interaction ◽  
Road User ◽  
Mutual Trust ◽  
Responsibility Attribution ◽  
Right Of Way ◽  
The Difference ◽  
The Right ◽  
Almost All

Children of 6 to 9 years and adults judged a story protagonist's degree of blame for a traffic accident. All stories depicted a collision between a protagonist, who had the right of way, and another road user. Stories differed, however, in protagonist's second-order belief about the other road-user's knowledge. For instance, in one story, the protagonist mistakenly thought that the other had noticed her coming and that she could therefore rely on him abiding by the priority rule (principle of mutual trust) and grant her the right of way. This story contrasted with one where the protagonist knew that the other had not seen her and so was not justified in claiming priority. Most 7 and 8-year-old children understood the difference in second-order belief and about half of them were also able to make the correct responsibility attribution that the mistaken protagonist, thinking the other character knew, was less to blame for the accident than the one who knew about the other's ignorance. By 9 years, almost all children understood second-order beliefs and three-quarters were also able to make the correct responsibility attribution. The application of second-order beliefs to the principle of mutual trust is discussed in relation to communication failures and cooperative interaction.

scholarly journals Design Criteria and Location of Snow Fences

1985 ◽  
Vol 6 ◽  
pp. 68-70 ◽  
Author(s):  
Harald Norem
Keyword(s):  
Minimum Distance ◽  
Storage Capacity ◽  
Windward Side ◽  
Design Criteria ◽  
Total Density ◽  
Design Considerations ◽  
Drifting Snow ◽  
Snow Fence ◽  
Snow Model ◽  
Snow Fences

The paper describes experience gained in Norway regarding the design criteria and use in practice of snow fences. The paper is based on theoretical studies on drifting snow, model experiments and experience accumulated through practical consulting work. Snow fence design is a compromise between the storage capacity and minimization of dimensioning forces. Design considerations include fence height H, total snow fence density, and the gap between ground and fence. A gap of 0.15H - 0.2H and a total density of 45% are usually recommended. On ridge crests the gap can be reduced to 0.1H and in areas where snow depths exceed 2.0 m, it can be increased to 0.3H. In such cases the fence density should be varied such that the total density, including the gap, will remain near 45%. The height of the snow fences should be kept within 3.5 -4.5 m and the snow fences should be erected on the windward side of obstacles that create snowdrifts. The minimum distance from fence to road should not be less than 15H; in certain circumstances in coastal climate, this can be reduced to 10H.

scholarly journals Field experiments on “living” snow fences

1998 ◽  
Vol 26 ◽  
pp. 217-220 ◽  
Author(s):  
Florence Naaim-Bouvet ◽  
Pierre Mullenbach
Keyword(s):  
Field Experiments ◽  
Snow Accumulation ◽  
Real Problem ◽  
Effective Height ◽  
Natural Plant ◽  
Drifting Snow ◽  
Snow Fence ◽  
Limited Scale ◽  
Living Fences ◽  
Snow Fences

In Franee, drifting snow is generally controlled using artificial snow fences. Living snow fences are not a new concept but they have only been used on a limited scale. Research directly related to natural plant barriers is limited. We therefore decided to study the behaviour of species that would survive and grow satisfactorily in the French Alps.In the first experiment, we compared the storage capacity of several different kinds of living fences consisting of pruned spruces, unpruned spruces and sorbs.Field observations during the winter of 1995-96 proved that deciduous trees such as sorbs are effective, and that pruning the lower 50 cm is not effective at the end of the season because of the weight of snow on low branches.However, the use of natural plant barriers has disadvantages: a living snow fence takes time to reach an effective height and is difficult to establish on windy sites at a high altitude. This is a real problem. Therefore, in a second experiment, we studied the death rate of larches planted behind a fence. We noticed that the snow fence had several effects, snow accumulation (until the planted trees grew up) and protection of the planted trees.

Safety Service Patrol Uniforms: Technology, National Practices, and Operator Preferences

2019 ◽  
Vol 2673 (11) ◽  
pp. 456-465
Author(s):  
Grady Carrick ◽  
Katherine Belmore
Keyword(s):  
United States ◽  
Traffic Control ◽  
National Level ◽  
Past Research ◽  
The United States ◽  
Right Of Way ◽  
Technical Requirements ◽  
Control Devices ◽  
The Right ◽  
Almost All

Safety service patrols operate in more than 40 states and territories in the United States and each program operates with unique vehicles, uniforms, and equipment. Despite the variety of operator uniforms, legal and technical requirements at a national level dictate some choices, though color and style are largely at the discretion of states. Past research confirms that high-visibility safety apparel (HVSA) increases visibility. Biomotion markers on the joints further enhance visibility. The Manual on Uniform Traffic Control Devices specifies that personnel working in the right-of-way wear a Class 2 or 3 HVSA. A survey of states where service patrols operate found the majority use high-visibility yellow-green over red-orange, and Class 3 garments are preferred over Class 2. In relation to the base uniform, there is a mixture of maintenance-type uniforms, polo shirts, and no uniform specification at all. In a survey of Florida service patrol program managers and operators, conveying professionalism, comfort, and safety were the most valued aspects of uniforms. Operators understand the need to care and maintain HVSA, but may overestimate their ability to be seen at night by between two and four times the actual distance they are visible. When given a choice, operators preferred dark trousers with biomotion markers, though they were roughly split between the polo shirt/vest option and the integrated HVSA shirt that does not require use of a vest. A uniform protective outerwear was favored by almost all operators, and a ball cap was the headwear of choice.

scholarly journals Design of Living Barriers to Reduce the Impacts of Snowdrifts on Illinois Freeways

2020 ◽  
Author(s):  
John Petrie ◽  
Yan Qi ◽  
Mark Cornwell ◽  
Md Al Adib Sarker ◽  
Pranesh Biswas ◽  
...  
Keyword(s):  
Design Procedure ◽  
Weather Conditions ◽  
Field Testing ◽  
Design Guidelines ◽  
Blowing Snow ◽  
Winter Maintenance ◽  
Right Of Way ◽  
On The Road ◽  
Snow Fences ◽  
The Right

Blowing snow accounts for a large part of Illinois Department of Transportation’s total winter maintenance expenditures. This project aims to develop recommendations on the design and placement of living snow fences (LSFs) to minimize snowdrift on Illinois highways. The research team examined historical IDOT data for resource expenditures, conducted a literature review and survey of northern agencies, developed and validated a numerical model, field tested selected LSFs, and used a model to assist LSF design. Field testing revealed that the proper snow fence setback distance should consider the local prevailing winter weather conditions, and snow fences within the right-of-way could still be beneficial to agencies. A series of numerical simulations of flow around porous fences were performed using Flow-3D, a computational fluid dynamics software. The results of the simulations of the validated model were employed to develop design guidelines for siting LSFs on flat terrain and for those with mild slopes (< 15° from horizontal). Guidance is provided for determining fence setback, wind characteristics, fence orientation, as well as fence height and porosity. Fences comprised of multiple rows are also addressed. For sites with embankments with steeper slopes, guidelines are provided that include a fence at the base and one or more fence on the embankment. The design procedure can use the available right-of-way at a site to determine the appropriate fence characteristics (e.g., height and porosity) to prevent snow deposition on the road. The procedure developed in this work provides an alternative that uses available setback to design the fence. This approach does not consider snow transport over an entire season and may be less effective in years with several large snowfall events, very large single events, or a sequence of small events with little snowmelt in between. However, this procedure is expected to be effective for more frequent snowfall events such as those that occurred over the field-monitoring period. Recommendations were made to facilitate the implementation of research results by IDOT. The recommendations include a proposed process flow for establishing LSFs for Illinois highways, LSF siting and design guidelines (along with a list of suitable plant species for LSFs), as well as other implementation considerations and identified research needs.

ANALYSIS OF REGULATIONS REGARDING THE SETTLEMENT OF ISSUES ON THE REMOVAL AND RECOVERY OF PLANTATIONS IN THE RIGHT-OF-WAY OF PUBLIC ROADS

2020 ◽  
pp. 55-60
Author(s):  
Nataliia Kharytonova ◽  
Olha Mykolaienko ◽  
Tetyana Lozova
Keyword(s):  
Traffic Safety ◽  
Climatic Factors ◽  
Visual Orientation ◽  
Right Of Way ◽  
Adverse Weather ◽  
Overhead Power Lines ◽  
The Right ◽  
Neck Diameter ◽  
Proper Operation

Greening of roads contributes to the protection of roads and their elements from influence of adverse weather and climatic factors; it includes the measures for improvement and landscaping of roads, ensures the protection of roadside areas from transport pollution, provides visual orientation of drivers. The solution of these issues will ensure creation and maintenance of safe and comfortable conditions for travelers. Green plantings in the right-of-way road area include woody, bushy, flower and grass vegetation of natural and artificial origin. For proper operation of public roads and satisfaction of other needs of the industry, there may be the need in removing the greenery. The reason for the removal of greenery in the right-of-way road area may be due to the following factors: construction of the architectural object, widening of the motor road, repair works in the security zone of overhead power lines, water supply, drainage, heating, telecommunications facilities, cutting of hazardous, dry and fautal trees, as well as self-grown and brushwood trees with a root neck diameter not exceeding 5 cm, elimination of the consequences of natural disasters and emergencies. The removal of plantations in the right-of-way area is executed in order to ensure traffic safety conditions and to improve the quality of plantations composition and their protective properties. Nowadays, in Ukraine there is no clear procedure for issuing permits for removing of such plantations. In order to resolve this issue, there is a need in determining the list of regulations in the area of forest resources of Ukraine and, if needed, the list of regulatory acts that have to be improved; to prepare a draft of the regulatory legal act that would establish the procedure of plantations cutting, the methodology of their condition determination, recovery costs determination, the features of cutting. Keywords: plantations, cutting, right-of-way, woodcutting permit, order.

Development and validation of the Global Competency Scale(GCS)

2012 ◽  
Vol 25 (4) ◽  
pp. 801-831
Author(s):  
Sangchoong Roh ◽  
Hongsik Jung ◽  
Youngwon Suh
Keyword(s):  
Training System ◽  
Global Competency ◽  
Human Resource Department ◽  
Survey Results ◽  
Systematic Selection ◽  
Gcs Score ◽  
The Right ◽  
Development And Validation ◽  
Criterion Variables ◽  
And Training

As the world economy is becoming globalized, more domestic businesses are branching to overseas. Thereupon the number of expatriate workers who are getting assigned to overseas are increasing, and needs for systematic selection and training system for overseas expatriate workers are in dire needs. Nevertheless researches in this area are not enough and still inadequate level domestically. Therefore we developed the Global Competency Scale (GCS) with the purpose of the local businesses to use it to predict the possibility of successful overseas job performance and to select and train the right overseas expatriate workers. To develop the scale we conducted researches on documentations and interviews with former overseas expatriate workers and expatriate program managers in human resource department(HRD). Based on these results we developed 14 initial factors with 138 items. Using theses items we conducted both on & offline survey to people who work at global and multinational companies in Korea. With the 381 people's survey results, we implemented the cross validity. After cross validating we generated final 6 factors with 24 items. The GCS score we developed in this research shows that the degree of their goal achievement during past overseas experience and level of their satisfaction was significantly high in those criterion variables proving the criterion-related validity. Especially the GCS we developed in this research shows that after controlling the effect of English skills, still appear to have significant effect on criterion variables. Finally based on research results we discussed academical and operational implication and limitations for the further researches.

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