THE INFLUENCE OF FREEZING YOUNG CONCRETE ON ITS SUBSEQUENT INCREASE IN STRENGTH /IN RUSSIAN/

THE OBJECTIVE WAS TO DETERMINE THE CAUSES OF THE INCREASE IN THE FINAL STRENGTH OF CONCRETE SUBJECTED TO FREEZING AT AN EARLY AGE, AND TO ESTABLISH CONDITIONS UNDER WHICH THIS INCREASE IN STRENGTH CAN BE OBTAINED. SAMPLES OF PURE PASTE, CONCRETE, AND AGGLOPORITE CONCRETE (VARYING IN THEIR WATER/CEMENT RATIO) WERE SUBJECTED TO FREEZING CYCLES (TEMPERATURE -15/-20 DEGREES C FOR 5 TO 6 HOURS) 3, 8, AND 24 HOURS AFTER MANUFACTURE AND WERE THEN CURED IN HUMID ENVIRONMENT AT A TEMPERATURE OF 15-20 DEGREES C. THE COMPRESSIVE STRENGTH WAS MEASURED 24 HOURS, 7 AND 28 DAYS AFTER FREEZING. THE ELECTRICAL RESISTIVITY OF PURE PASTE SAMPLES DURING FREEZING, THAW AND CURING WAS ALSO MEASURED TOGETHER WITH THE VARIATIONS IN TEMPERATURE OF THE SAMPLES. RESULTS ARE PRESENTED IN THE FORM OF 6 GRAPHS EXPRESSING THE RELATIONS BETWEEN ELECTRICAL RESISTIVITY, STRENGTH, TEMPERATURE, AND CURING TIME OF PURE PASTE AND CONCRETE SAMPLES. BASED ON THOSE RESULTS, A CRITICAL AGE FOR CONCRETE IS DEFINED: IF FREEZING OCCURS BEFORE IT, FINAL STRENGTH IS LOWER THAN THAT OF CONTROL SAMPLES; IF FREEZING OCCURS AFTERWARDS, THE FINAL STRENGTH IS HIGHER THAN THAT OF THE CONTROL. THIS AGE DEPENDS ON THE WATER/CEMENT RATIO AND CEMENT COMPOSITION AND CORRESPONDS TO THE END OF SETTING. IN THE CASE OF CEMENT PASTE, IT CAN BE DETERMINED BY USING VARIOUS TYPES OF MEASURING APPARATUS. /LCPC/RRL/

• Supplemental Notes:
  • No 2, pp 30-34, 6 FIG, 1 TAB, 6 REF
• Authors:
  • Akhverdov, I N
  • Kaplan, E L
• Publication Date: 1968

Media Info

• Serial:
  • Beton I Zhelezobeton /Ussr/

Subject/Index Terms

• TRT Terms: Age; Cement; Compressive strength; Concrete; Concrete curing; Electrical resistivity; Freezing; Graphics; Pastes; Strength of materials; Temperature; Water cement ratio
• Uncontrolled Terms: Graphical analysis
• Old TRIS Terms: Resistivity
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00212882
• Record Type: Publication
• Source Agency: Road Research Laboratory /UK
• Files: TRIS
• Created Date: Sep 28 1970 12:00AM