REPORT ON THE USE OF THE TROXLER 104 PROBE AND 115 GAUGE FOR ASPHALT CONTENT DETERMINATIONS

TESTS WERE CONDUCTED TO DETERMINE THE POSSIBILITY OF USING A COMMERCIAL NEUTRON SURFACE MOISTURE GAUGE FOR FAST AND ACCURATE ASPHALT CONTENT DETERMINATIONS. SINCE THE HYDROCARBON CONCENTRATION OF A GIVEN GRADE OF ASPHALT IS RELATIVELY CONSTANT, THE ASPHALT PERCENTAGE OF A GIVEN MASS CAN BE DETERMINED INDIRECTLY BY MEASURING THE HYDROGEN CONTENT. THE HYDROGEN CONTENT OF A GIVEN MASS IS DIRECTLY RELATED TO THE THERMALIZATION OF NEUTRONS AS THE NEUTRONS PASS THROUGH THE MASS. THE PERCENT OF THERMALIZATION CAN BE MEASURED BY USING A HIGH ENERGY NEUTRON SOURCE (RADIUM- BERYLLIUM) AND A DETECTOR RESPONDING ONLY TO THERMALIZED (SLOW) NEUTRONS. THIS DESCRIBES THE TROXLER MODEL 104-115 SURFACE MOISTURE GAUGE. A PORTABLE SCALER IS USED TO RECORD THE NUMBER OF THERMALIZED NEUTRONS PER MINUTE OF COUNTING REFERRED TO ONLY AS COUNT RATE. THE RELATIONSHIP MUST THEN BE ESTABLISHED BETWEEN COUNT RATE AND ASPHALT CONTENT. TEST RESULTS SHOWED A VARIATION IN CALIBRATION. THE ESTIMATED ERROR FOR ANY ONE OF THE CALIBRATION CURVES IS SATISFACTORY FOR SOIL MOISTURE DETERMINATION (HYDROGEN CONTENT) WHEN ONE IS CONSIDERING QUALITY CONTROL IN COMPACTION OF BASE, SUB- BASE AND EMBANKMENT MATERIALS. HOWEVER, THEY ARE NOT WITHIN SPECIFICATIONS FOR QUALITY CONTROL OF ASPHALTIC CONCRETE PRODUCTION PLUS OR MINUS 0.4% ASPHALT.

• Supplemental Notes:
  • Report 55-c, 10 PP, 3 FIG, 2 TAB, 4 REF
• Authors:
  • Todor, P C
• Publication Date: 1966-3-30

Media Info

• Serial:
  • Florida State Road Dept Research Bull

Subject/Index Terms

• TRT Terms: Asphalt content; Base course (Pavements); Calibration; Compaction; Embankments; Hydrogen; Measurement; Moisture meters; Neutrons; Nuclear radiation; Quality control; Sensors; Soil compaction; Soil water; Subbase materials
• Old TRIS Terms: Embankment compaction; Neutron sources; Radiation counters /sensors/; Slow neutrons
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00216277
• Record Type: Publication
• Files: TRIS
• Created Date: May 6 1994 12:00AM