SNOW CONTROL STRUCTURES
The technology of snow control structures has recently advanced to the point that snow control is now possible even for the severe conditions at Thompson Pass. This Pass, where the Richardson Highway crosses the Chugach Mountains, has an estimated average annual snowfall of 400 inches, and a design wind speed of 120 mph with gusts to 160 mph. The first significant use of large snow control structures at Thompson Pass was begun by DOT'PF in 1982 with the installation of a "jet roof" as shown in the top and middle photos. This structure is designed to boost wind velocities, increasing snow movement to eliminate a cornice buildup in the notch-shaped roadway cut at the top of the pass. Cornices building up during storms have created a hazard for snowplow operators trying to clear the cut. In 1983 a 600-foot-long by 15-foot-high "Wyoming" type snow fence was also constructed in the Pass. This fence produces an effect opposite to that of the jet roof. It decreases wind velocity, so that much of the blowing snow settles before it reaches the highway. This fence consists of 6" x 15" steel I-beam posts on 10' centers, with 2" x 6" wood rails and 6" gaps between rails. Wind resistance is provided by cables and buried anchors. This fence design was originally developed cooperatively by the Wyoming Highway Department and the U. S. Forest Service's Rocky Mountain Forest and Range Experiment Station. (Author)
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Authors:
- Esch, D C
- Publication Date: 1984-8
Media Info
- Pagination: 2 p.
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Serial:
- Research notes: Division of Planning and Programming
- Volume: 4
- Issue Number: 2
- Publisher: Alaska Department of Transportation and Public Facilities
Subject/Index Terms
- TRT Terms: Field tests; Prevention; Snow and ice control; Snow fences; Snowdrifts; Structural design
- Subject Areas: Highways; Maintenance and Preservation; Security and Emergencies; I62: Winter Maintenance;
Filing Info
- Accession Number: 00390228
- Record Type: Publication
- Files: TRIS, STATEDOT
- Created Date: Nov 30 1984 12:00AM