PORE STRUCTURES AND SURFACE AREAS OF HARDENED PORTLAND CEMENT PASTES BY NITROGEN ADSORPTION

THE INVESTIGATIONS WERE PERFORMED ON 5 HARDENED PASTES OF A TYPE I PORTLAND CEMENT, HAVING INITIAL WEIGHT RATIOS OF WATER TO CEMENT OF 0.35, 0.40, 0.50, 0.57, AND 0.70, AND HYDRATED FOR 12, 12, 12, 2 1/2, AND 2 1/2 YEARS, RESPECTIVELY. THE PERCENTAGE HYDRATION RANGED FROM 90 TO 98 PERCENT. NITROGEN ADSORPTION AND DESORPTION ISOTHERMS WERE DETERMINED FOR ALL PASTES AT THE BOILING POINT OF NITROGEN, FROM LOW PRESSURES TO ALMOST THE SATURATION PRESSURE. THE B.E.T. SURFACE AREAS WERE CALCULATED, AND THE PORE SPACE ACCESSIBLE TO NITROGEN WAS OBTAINED BY A SLIGHT EXTRAPOLATION OF THE ISOTHERMS. IN ADDITION, PORE STRUCTURE ANALYSIS WAS MADE FOR 3 OF THE 5 PASTES BY THE METHOD OF CRANSTON AND INKLEY. THE SPECIFIC SURFACE AREAS OF THE 5 PASTES WERE ALSO DETERMINED BY WATER VAPOR ADSORPTION, AND THE TOTAL POROSITY TO WATER WAS MEASURED. /PCA/

• Authors:
  • Mikhail, R S
  • Copeland, L E
  • Brunauer, S
• Publication Date: 0

Media Info

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

Subject/Index Terms

• TRT Terms: Adsorption; Hardness; Hydration; Nitrogen; Pastes; Pores; Porosity; Portland cement; Surfaces; Water cement ratio
• Uncontrolled Terms: Pores; Surface area
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213606
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 167
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM