WATER-VAPOR ADSORPTION-DESORPTION CHARACTERISTICS OF SELECTED LIGHTWEIGHT CONCRETE AGGREGATES

WATER-VAPOR ADSORPTION-DESORPTION ISOTHERMS WERE DETERMINED FOR 15 LIGHTWEIGHT AGGREGATES, AND INTERNAL SURFACE AREAS WERE CALCULATED. ALTHOUGH OF HIGH POROSITY, THE LIGHTWEIGHT AGGREGATES HAD SURFACE AREAS COMPARABLE TO THE SURFACE AREAS OF EQUAL WEIGHTS OF DENSE CONCRETE AGGREGATE. THE AMOUNT OF SORBED WATER HELD BY THESE LIGHTWEIGHT AGGREGATES, WHEN DRIED TO EQUILIBRIUM AT RELATIVE HUMIDITIES LESS THAN 75 PERCENT, IS EXTREMELY SMALL COMPARED TO THE AMOUNTS OF WATER ABSORBED BY THE SAME AGGREGATES WHEN IMMERSED IN WATER. APPLICATIONS OF THESE ADSORPTION-DESORPTION DATA TO THE PROBLEMS OF DRYING LIGHTWEIGHT CONCRETE MATERIALS, FIRE RESISTANCE OF LIGHTWEIGHT STRUCTURAL CONCRETES, AND FREEZING-AND-THAWING DURABILITY ARE DISCUSSED. /PCA/

• Authors:
  • Landgren, R
• Publication Date: 0

Media Info

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

Subject/Index Terms

• TRT Terms: Desorption; Drying; Fire resistance; Freeze thaw durability; Hygroscopic coefficient; Lightweight aggregates; Lightweight concrete; Surfaces
• Uncontrolled Terms: Surface area
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213616
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 178
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM