Accession Number : AD0837529

Title :   RESEARCH, DEVELOPMENT, AND PROTOTYPE PRODUCTION OF AN ULTRAVIOLET SENSING SOIL MOISTURE METER.

Descriptive Note : Final rept. 1 Mar-27 Aug 67,

Corporate Author : GEOTECH GARLAND TX

Personal Author(s) : Cohen, Jerald B.

Report Date : AUG 1967

Pagination or Media Count : 40

Abstract : A research program was conducted to determine feasibility of measuring moisture content of soils by measuring the amount of ultravilet light transmission through moisture contained in a soil analog encased in a quartz-granule wafer emplaced in the soil. Results obtained from many combinations of soil analogs and system geometry indicate that the concept is operationally impractical. Selected instrumentation developed for the program was reapplied to pursue investigation of promising variations of the initial concept. One variation involved critical angle refractometry. Under laboratory conditions, refractometer-type systems repeatedly yielded signal outputs directly correlative with the percent (moisture) saturation of all soil samples provided. This performance was achieved independent of soil temperature and variations in index of refraction of the soil moisture. Field testing of critical angle refractometers is necessary for establishing the performance of, and specifications for, any operational units. A promising configuration for field test units was prepared. (Author)

Descriptors :   (*SOILS, MOISTURE), (*ULTRAVIOLET DETECTORS, FEASIBILITY STUDIES), LIGHT TRANSMISSION, QUARTZ, GEOMETRY, INSTRUMENTATION, REFRACTIVE INDEX, SAMPLING, REFRACTION, PERFORMANCE(ENGINEERING), TEMPERATURE, PERIODIC VARIATIONS, REFLECTION, TEST METHODS, ACCURACY, SPECIFICATIONS.

Subject Categories : Soil Mechanics
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE