Consultant, Wiss, Janney, Elstner Associates, Inc., Northbrook, IL
Five mixtures were prepared from pure chemicals (tricalcium aluminate, calcium hydroxide, gypsum and 6% sulfurous acid) to examine the reactions of calcium sulfite with calcium aluminate by scanning electron microscope (SEM) procedures. Subsequently, two series of concrete mixes using the pozzolan cements were prepared: one to investigate the relative effects of calcium sulfite and calcium sulfate at constant calcium hydroxide and fly ash levels and the second to investigate the relative effects of sulfite and calcium hydroxide at a constant fly ash level. A comparison of effects of sulfite and sulfate and a comparison of calcium hydroxide and calcium sulfite were made using values of compressive strength and SEM analyses of the samples. Photomicrographs of microstructures and X-ray analyses were used to illustrate the findings.
Paper ID: CCA10365J