A STUDY OF THE FREEZE-THAW CHARACTERISTICS OF SELECTED NEVADA MINERAL AGGREGATES

THE OBJECTIVES WERE: TO EXAMINE MINERAL AGGREGATES THAT WERE USED IN PORTLAND CEMENT CONCRETE HIGHWAY STRUCTURES AND PAVEMENTS; TO NOTE THE RESISTANCE OR LACK OF RESISTANCE OF THESE MINERALS TO FREEZE-THAW CYCLES; TO DETERMINE WHICH MATERIALS ARE LIKELY TO BE EXCESSIVELY DAMAGED BY EXPOSURE; AND TO DETERMINE THE EFFECT OF THE MOST FREQUENTLY USED METHODS IN PROTECTING PORTLAND CEMENT CONCRETE STRUCTURES FROM FREEZE-THAW DAMAGES. A SIMPLIFIED DISCUSSION, MEANING THAT FREE BOUNDARIES ARE ASSUMED FOR AGGREGATE SURFACES, IS PRESENTED AS A MEANS OF UNDERSTANDING THE COMPLEX MECHANISMS OF FROST DAMAGE IN AGGREGATESE CONTAINED IN CONCRETE. TABULAR DATA, SUPPLEMENTED BY GRAPHICAL DATA AND DISCUSSIONS, ARE PRESENTED FOR (1) PROPERTIES OF TYPE II CEMENT, (2) PETROGRAPHIC DESCRIPTION OF SAMPLES, (3) PETROGRAPHIC PERCENTAGES PRESENT IN AGGREGATES, (4) PROPERTIES OF COARSE AGGREGATES, (5) PROPERTIES OF FINE AGGREGATES, (6) DURABILITY COMPARISONS, WITH AND WITHOUT AIR ENTRAINMENT, (7) RELATIONSHIPS OF LONGITUDIANL DIMENSIONAL STABILITY, (8) PERMEABILITY TEST RESULTS, AND (9) CAPILLARY PORE DIAMETERS OF MINERAL AGGREGATES. THE FOLLOWING RECOMMENDATIONS WERE SUGGESTED: (1) ALL CONCRETE, POURED IN AREAS WHERE CONTINUOUS FROST DAMAGE IS AT ALL POSSIBLE, SHOULD BE SPECIFIED TO CONTAIN A MINIMUM OF 5% ENTRAINED AIR MEASURED AT THE TIME AND SITE OF PLACEMENT. (2) SPECIMENS USED IN CUMULATIVE LENGTH CHANGE TEST SHOULD EXPERIENCE NO MORE THAN AN OVERALL INCREASE IN LENGTH OF 0.001 INCH IN A 10 IN. GAGE LENGTH AFTER 7 CYCLES (1 DAY) OF FREEZE-THAW IN KEEPING WITH ASTM C290-63T: SHOULD THE SPECIMENS LENGTH EXCEED 0.002 INCH IN 14 CYCLES (2 DAYS), THE MATERIAL SHOULD BE STUDIED IN-DEPTH IN A LABORATORY BEFORE BEING CONSIDERED FOR FIELD USE. (3) AN IN-DEPTH STUDY OF AGGREGATE PORE SYSTEMS SHOULD BE CONDUCTED FOR ASCERTAINING A STATISTICAL CORRELATION BETWEEN THE VARIOUS PORE PROPERTIES AND THE DURABILITY OF INDIVIDUAL AGGREGATES. (4) A RELIABLE, FULLY ELECTRONICALLY INSTRUMENTED, FIRST-CYCLE FREEZE DISTILLATION TEST POSSESSING POSITIVE CONTROL OVER THE RATE OF FREEZING SHOULD BE DEVELOPED. (5) THE POSSIBILITY OF DECREASING THE CURING TIMES (NOW 14 DAYS) SHOULD BE CONSIDERED TO PERHAPS 7 DAYS.

• Corporate Authors:

  University of Nevada, Las Vegas

  Department of Civil and Environmental Engineering
  4505 Maryland Parkway, P.O. Box 454015
  Las Vegas, NV  United States  89154-4015
• Authors:
  • Breese, C R
• Publication Date: 1970-8

Media Info

• Pagination: 121 p.
• Serial:
  • Issue Number: 38

Subject/Index Terms

• TRT Terms: Air entrainment; Capillarity; Coarse aggregates; Concrete curing; Fine aggregates; Freeze thaw durability; Frost damage; Geological surveying; Graphics; Mineral aggregates; Permeability; Petrography; Portland cement concrete
• Uncontrolled Terms: Graphical analysis
• Old TRIS Terms: Freezing thawing effects; Mineral aggregate testing; Petrographic investigations
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00217922
• Record Type: Publication
• Report/Paper Numbers: Eng Rept
• Files: TRIS
• Created Date: Dec 11 1973 12:00AM