Accession Number : AD0684406

Title :   SURFACE HARDENING OF COMPACTED SNOW BY CONTROLLED SOLAR RADIATION ABSORPTION.

Descriptive Note : Technical note Jul-Nov 65,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CALIF

Personal Author(s) : Stehle,Nancy S.

Report Date : NOV 1965

Pagination or Media Count : 20

Abstract : The snow surfaces of compacted-snow roads and runways often do not have adequate surface hardness and wearing ability for repeated traffic. Laboratory tests were conducted at the Naval Civil Engineering Laboratory to study the increase in surface hardness and wearing ability of compacted snow by melting and refreezing the surface snow through controlled absorption of solar radiation by black plastic on the snow surface. In 6- to 8-hour test exposures, the greatest increase in shear strength in the top 6 inches of the snow, the measure of surface hardness for these tests, occurred at +5F after 6-1/2 hours of exposure to 1.10 Langleys/min, equal to 1.1 gm cal/sq cm/min or 243.3 Btu sq ft/hr. (Author)

Descriptors :   (*SNOW, TRAFFICABILITY), SURFACE PROPERTIES, HARDNESS, ABSORPTION, EXPOSURE(PHYSIOLOGY), ATMOSPHERIC TEMPERATURE, SHEAR STRESSES, COMPRESSIVE PROPERTIES, SOLAR RADIATION, ROADS, RUNWAYS, POLAR REGIONS, ANTARCTIC REGIONS

Subject Categories : Snow, Ice and Permafrost

Distribution Statement : APPROVED FOR PUBLIC RELEASE