INVESTIGATION OF TRIVALENT IRON SALTS AS ADMIXTURES ACCELERATING THE HARDENING OF CONCRETE
AN INVESTIGATION WAS MADE OF THE MECHANISM OF ACTION OF IRON SALTS /FERRIC CHLORIDE, FERRIC SULFATE AND FERRIC NITRATE/ THE TESTS SHOWED THAT THESE HIGHLY HYDROLIZED SALTS DUE TO THE ACID REACTION OF THEIR SOLUTION CAUSED THE CHEMICAL TRANSFORMATIONS AT THE INITIAL STAGE WITH THE TRANSITION OF IRON FROM CATION TO ANION. AT THE INITIAL STAGE OF HARDENING, THE REACTION PRODUCTS OF FERRIC SULFATE WITH CEMENT ARE THE FERRIC HYDROXIDE GEL, GYPSUM, AND CALCIUM FERRITES. LATER THE FORMATION OF CALCIUM HYDROSULFOFERRITES IS OBSERVED. THE INTERACTION OF IRON SALTS WITH CEMENT IS ACCOMPANIED BY A NEUTRALIZING REACTION, WHICH RAISES THE TEMPERATURE OF CEMENT PASTE AND ACCELERATES THE HYDRATION OF CEMENT. THE INVESTIGATED ADMIXTURES ACCELERATE THE HARDENING OF CONCRETE, SIMULTANEOUSLY RAISES THE SULPHATE RESISTANCE, RESISTANCE TO WEAR AND REDUCES AS WELL ITS PERMEABILITY. THE TESTS SHOW THAT FERRIC SULFATE ACCELERATED CONSIDERABLY THE HARDENING OF CONCRETE IN THE INITIAL PERIOD, THIS SERVED AS THE BASIS FOR ITS SUCCESSFUL APPLICATION AS AN ADMIXTURE FOR THE SPRAY CONCRETE. ALL THE INVESTIGATED ADMIXTURES, ESPECIALLY FERRIC SULFATE LOWERS THE WORKABILITY OF CONCRETE. /CRIC/FESR/RRL/A/
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Supplemental Notes:
- Report 111-IV/10, PP 169-180, 4 FIG, 4 TAB, 3 REF
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Authors:
- Rosenburg, T I
- Alimov, S S
- Gueseinov, A A
- Ratinov, V B
- Conference:
- Publication Date: 1967
Subject/Index Terms
- TRT Terms: Accelerating agents; Admixtures; Cement; Chlorides; Concrete hardening; Durability; Hardness; Hydration; Iron compounds; Nitrates; Permeability; Salts; Sulfates; Workability
- Subject Areas: Highways; Materials;
Filing Info
- Accession Number: 00212943
- Record Type: Publication
- Source Agency: Road Research Laboratory /UK
- Files: TRIS
- Created Date: Aug 3 1970 12:00AM