ISSN: 1945-7553
CODEN: JTEVAB
Page Count: 9

Effect of Various Accelerating Chemical Admixtures on Setting and Strength Development of Concrete

Rosskopf, PA
Assistant director of Technical Services; chief of Concrete Section, Research and Development; and director of Research and Developmentmember of ASTM, Master Builders, Lee at Mayfield, Cleveland, Ohio

Linton, FJ
Assistant director of Technical Services; chief of Concrete Section, Research and Development; and director of Research and Developmentmember of ASTM, Master Builders, Lee at Mayfield, Cleveland, Ohio

Peppler, RB
Assistant director of Technical Services; chief of Concrete Section, Research and Development; and director of Research and Developmentmember of ASTM, Master Builders, Lee at Mayfield, Cleveland, Ohio

Abstract

A study of the rate of hardening of concretes which contain inorganic accelerators demonstrates the superior performance of calcium chloride. However, there are significant changes in the compressive strength of concretes at various ages when accelerators are employed. Calorimetric studies of cement mortars show the advantages as an accelerator that calcium chloride maintains over other inorganic salts. Also, calorimetric tests demonstrate what appears to be different mechanisms of acceleration between different kinds of accelerators. Differential thermal analysis (DTA) techniques were applied to a study of the effect of calcium chloride and calcium formate on the early stages of hydration of a cement. DTA patterns show definite differences between the function of the accelerators.

Keywords:
concretes, admixtures, hardening (materials), compressive strength, accelerating (chemistry), portland cements, organic salts, inorganic salts, halogen salts, calcium chlorides, heat measurement, differential thermal analysis, hydration, retardation

Paper ID: JTE10662J
DOI: 10.1520/JTE10662J
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