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Title: ROLE OF ROADWAY PLANTING DESIGN IN CONTROL OF DRIFTING SNOW
Accession Number: 00205146
Record Type: Component
Abstract: HIGHWAY LANDSCAPE DESIGNERS UTILIZING VEGETATION TO CONTROL DRIFTING SNOW MUST BE INTIMATE WITH THE CAUSES AND MANIFESTATIONS OF DRIFTING. THE APPROXIMATE WIND VELOCITY THAT WILL PICK UP SNOW AND CAUSE DRIFTING IS 15--25 MPH, DEPENDING ON WEIGHT AND MOISTURE CONTENT. THE CAPACITY OF WIND TO CARRY PARTICLES VARIES AS THE SQUARE OF ITS VELOCITY, I.E., A 40-MPH WIND SLOWED TO 20 MPH WILL LOSE 3/4 OF ITS CARRYING CAPACITY. DRIFT CONTROL IS THEREFORE A MATTER OF DECREASING WIND VELOCITY. THE SHAPE AND SLOPE OF CUTS AND FILLS WILL DETERMINE AIR FLOW AND HENCE THE NATURE OF DRIFT DESPOSITS. FROM THE ROCKIES TO THE ATLANTIC COAST WINDS FROM THE NORTHWEST CREATE THE GREATEST DRIFT HAZARDS. SOME STATES IN THE NORTHWEST EXPERIENCE PRIMARY DIFFICULTY FROM THE SOUTHWEST. THESE FACTORS OF VELOCITY, AIR FLOW, AND DIRECTION ARE THE MAIN ONES, ALONG WITH CLIMATE, IN DETERMINING THE HEIGHT AND SPACING OF VEGETATION, DISTANCE FROM THE HIGHWAY, NUMBER OF ROWS OF PLANTS, AND THE TYPE OF VEGETATION REQUIRED.
Supplemental Notes: No 1030, pp 23-31, 3 FIG, 4 PHOT, 5 REF. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
Authors: Hunter, W GPublication Date: 1962
Serial:
Highway Research Board Roadside Development Committee Reports
Publisher: Highway Research Board Media Type: Digital/other
TRT Terms: Uncontrolled Terms: Subject Areas: Design; Environment; Highways
Files: TRIS, TRB
Created Date: Dec 6 1971 12:00AM
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