THERMAL CONDUCTIVITY OF CONCRETE AT VERY LOW TEMPERATURES

THE THEORY AND PRACTICAL APPLICATION OF A NON-STEADY-STATE "HOT-WIRE" METHOD FOR MEASURING THE THERMAL CONDUCTIVITY OF CONCRETE AT TEMPERATURES RANGING GROM -250 TO 75 F ARE DISCUSSED IN DETAIL. A DETERMINATION REQUIRED ONLY 10 MINUTES. THERMAL CONDUCTIVITIES OF ROCK SPECIMENS WERE DETERMINED BY THE USE OF A "SPLIT-SPECIMEN" TECHNIQUE. THERMAL CONDUCTIVITIES OF SAND AND GRAVEL CONCRETE CONTAINING 5.5 BAGS OF CEMENT PER CUBIC YARD OF CONCRETE RANGED FROM 32 BTU/ (HR)(SQ FT)(F/IN.) AT -250 F TO 23 AT 75 F FOR MOIST CONCRETE, AND RANGED FROM 25 AT -250 F TO 19 AT 75 F FOR CONCRETE EQUILIBRATED AT 50 PERCENT RELATIVE HUMIDITY. BY CONTRAST, THE THERMAL CONDUCTIVITY OF AN EXPANDED SHALE LIGHTWEIGHT AGGREGATE CONCRETE IN A MOIST CONDITION WAS NEARLY CONSTANT AT ABOUT 6 BTU/(HR)(SQ FT) (F/IN.) OVER THE SAME TEMPERATURE RANGE. /PCA/

• Authors:
  • Lentz, A E
  • Monfore, G E
• Publication Date: 0

Media Info

• Serial:
  • Portland Cement Assoc R & D Lab Bull
  • Issue Number: 0

Subject/Index Terms

• TRT Terms: Anemometers; Concrete; Expanded shale aggregates; Lightweight aggregates; Lightweight concrete; Low temperature; Measurement; Sandy gravels; Thermal conductivity
• Old TRIS Terms: Hot wire anemometers
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213620
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 182
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM