00215796

Component

http://onlinepubs.trb.org...s/hrr/1966/107/107-001.pdf

THE NUCLEAR REACTIONS WHICH GAMMA RADIATION MAY UNDERGO IN A MATERIAL OF MEDIUM ATOMIC WEIGHT, SUCH AS SOIL, ARE DISCUSSED AND RELATED TO THE PROPERTIES OF BACKSCATTERING DENSITY GAGES. THEORETICAL REASONING AND EXPERIMENTAL EVIDENCE ARE PRESENTED TO SHOW THAT THE EFFECT OF THE CHEMICAL COMPOSITION OF THE MATERIAL MAY BE ELIMINATED WHEN' /A/ THE DETECTOR SEES MATERIAL NEAR THE SOURCE, AND /B/ PHOTONS OF ENERGY BELOW 0.1 MEV ARE NOT DETECTED. THE LATTER MAY BE ACHIEVED WITH A SCINTILLATION COUNTER AND PULSE SELECTOR OR BY PLACING IRON FILTERS IN FRONT OF A GEIGER-MULLER TUBE. THE GEOMETRY DEFINED BY /A/ CAUSES THE PEAK IN THE CALIBRATION CURVE TO MOVE TO A DENSITY SO HIGH THAT THE COUNT RATE BECOMES A UNIQUE MEASURE OF DENSITY, RISING OVER THE ENTIRE RANGE OF DENSITY FROM 0 TO 160 PCF. ERRORS IN THE DENSITY READING DUE TO THE STATISTICS OF NUCLEAR COUNTING AND SURFACE ROUGHNESS ARE DISCUSSED. /AUTHOR/

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01410062

pp 1-12

1966

Highway Research Record

Digital/other

Figures (9) ; References (27)

Analysis; Backscattering; Chemical composition; Density; Errors; Filters; Gamma rays; Measurement; Measuring instruments; Nuclear reactions; Reading; Scintillation counters; Soils; Texture

Geotechnology; Highways; Materials

TRIS, TRB

Nov 18 1994 12:00AM

• AGGREGATE PRODUCTION WITH NUCLEAR EXPLOSIVES
• DEVELOPMENT OF NUCLEAR DENSITY TESTS FOR HOT ASPHALT PAVEMENT
• EVALUATION OF DIRECT TRANSMISSION-TYPE NUCLEAR DENSITY GAGE FOR MEASURING IN-PLACE DENSITIES OF SOILS
• PROGRESS IN NUCLEAR EXCAVATION TECHNOLOGY