Title: Autogenous Healing of Cement Paste

Author(s): Kenneth R. Lauer and Floyd 0. Slate

Publication: Journal Proceedings

Volume: 52

Issue: 6

Appears on pages(s): 1083-1098

Keywords: no keywords

DOI: 10.14359/11661

Date: 6/1/1956

Abstract:
It is a recognized fact that cracks in concrete sometimes become "healed." This paper reports a study of the nature of the healing action, and of the increases in tensile strength measured perpendicular to the plane of the crack. Study was made of effects on healing of time of healing, conditions of curing, additions of lime and of fly ash, and cycles of wetting and drying. The healing action is caused by formation of crystals of calcium carbonate and calcium hydroxide in the cracks. Healing can increase tensile strength from 0 psi to 25 percent of normal tensile strength. It occurs far more rapidly under water than in air. Additions of lime and fly ash have little effect.