POZZOLANIC REACTIVITY STUDY OF FLYASH

IN RECENT YEARS MUCH INTEREST HAS BEEN SHOWN IN SOIL STABILIZATION METHODS UTILIZING THE POZZOLANIC REACTION. LIME-FLYASH STABILIZATION IS PROBABLY THE BEST KNOWN AND MOST THOROUGHLY INVESTIGATED OF THESE METHODS. UNFORTUNATELY, LITTLE IS KNOWN OF THE NATURE OF THE REACTION OR REACTIONS INVOLVED, OR OF THE REACTION PRODUCTS THAT ARE FORMED. THIS INFORMATION IS NEEDED FOR EVALUATING THE REACTANTS AND IMPROVING THE REACTION. THIS PAPER DESCRIBES A PROGRAM OF BASIC RESEARCH ON THE NATURE OF THE POZZOLANIC REACTION BETWEEN LIME AND FLYASH. SIX FLYASHES OF VARIOUS PHYSICAL AND CHEMICAL PROPERTIES WERE INVESTIGATED. THE REACTION BETWEEN FLYASHES AND CALCIUM HYDROXIDE WAS FOLLOWED BY MEANS OF AN ELECTROCONDUCTIVITY PROCEDURE. THE REACTION WAS STUDIED AT SEVERAL TEMPERATURES AND FOR SEVERAL CONCENTRATIONS. THE REACTION PRODUCTS WERE INVESTIGATED BY MEANS OF X-RAY DIFFRACTION AND DIFFERENTIAL THERMAL ANALYSIS TECHNIQUES. CALCIUM HYDROXIDE ABSORPTION TESTS, USING ELECTROCONDUCTIVITY PROCEDURES, ON FLYASHES GAVE ESSENTIALLY THE SAME EVALUATION RESULTS AS THOSE OBTAINED FROM COMPRESSIVE STRENGTH RESULTS. THE INFLUENCE OF TEMPERATURE ON THE REACTION WAS MOST SIGNIFICANT IN THE 20 TO 60 DEG C RANGE. A CRYSTALLINE REACTION PRODUCT WAS DETECTED, BUT THIS MAY BE A SECONDARY PRODUCT. AN EXPLANATION IS OFFERED FOR THE MECHANISM OF THE POZZOLANIC REACTION. THE RATE LIMITING STEP OF THE REACTIONS IS EXPLAINED ON THE BASIS OF DIFFUSION. /AUTHOR/

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00232450
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Aug 15 2004 2:43AM