UTILIZATION OF NATURAL ZEOLITE IN PORTLAND POZZOLAN CEMENT OF INCREASED SULFATE RESISTANCE

The objective of this paper is to characterize sulfate resistance of the mortars (cement to sand = 1:3 by weight, W/C = 0.6) made from blended portland pozzolan cement with 15 wt.% of zeolite, and to compare it to that of mortars made from normal portland cement and sulfate resistance portland cement. The improved sulfate resistance of mortars with portland pozzolan cement is caused by: 1. decreased tricalcium aluminate in the blended cement in comparison with that in normal portland cement; 2. decreased content of calcium hydroxide capable of reacting with a sulfate solution due to pozzolanic reaction of zeolite with the cement relative to that in normal portland cement; 3. ion-exchange capacity of zeolite to Ca 2+ ions; 4. negligible change in pore structure of portland pozzolan cement mortars compared to portland cement mortar which is characterized by significant conversion of capillary pores to gel pores, as a result of formation of voluminous reaction products of the sulfate attack. The results show that sulfate resistance of portland pozzolan cement was similar to that of the sulfate resistant portland cement.

• Corporate Authors:

  American Concrete Institute (ACI)

  38800 Country Club Drive
  Farmington Hills, MI  United States  48331
• Authors:
  • Janotka, I
  • Krajci, L
• Conference:
  • Fifth CANMET/ACI International Conference on Durability of Concrete
  • Location: Barcelona, Spain
  • Date: 2000-6-4 to 2000-6-9
• Publication Date: 2000

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 223-238

Subject/Index Terms

• TRT Terms: Calcium hydroxide; Ion exchange; Mortar; Porosity; Portland cement; Portland pozzolan cement; Sulfate resisting cement; Tricalcium aluminate
• Candidate Terms: Blended cement
• Uncontrolled Terms: Zeolite
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 00793940
• Record Type: Publication
• Report/Paper Numbers: SP 192-14
• Files: TRIS
• Created Date: Jun 28 2000 12:00AM