International Concrete Abstracts Portal

Title: Influence of Curing Method and Duration on Sorptivity of Concrete and Mortar

Author(s): W. P. S. Dias

Publication: Special publication

Volume: 170

Issue:

Appears on pages(s): 1073-1096

Keywords: Concretes; curing; durability; hot weather construction; mortars (materials); sorptivity.

Date: 7/1/1997

Abstract:
Cylindrical specimens of 100 mm x 100 mm dia. made of two concrete mixtures (1:2:4 and 1:1.5:3), two cement:sand mortars (1:3 and 1:5) and one cement: lime: sand mortar (1: 1: 5) were cured under varying conditions, i.e. , inside the laboratory (in air or water) and exposed to sunlight in hot weather outside the laboratory (wrapped in damp hessian or placed under a plastic sheet); the laboratory specimens in water were cured for varying durations, ranging from zero to 27 days after demolding. After these curing regimes, the specimens were allowed to dry in the laboratory, and sorptivity tests were carried out on them after coating their curved surfaces. The results revealed the following:- (i) For water-cured specimens, the sorptivity dropped appreciably during the first 7 days of curing, and less significantly thereafter; (ii) Curing outside the laboratory in damp hessian for 7 days yielded around the same sorptivities as for standard 27 days of water curing, while curing under plastic sheet gave the highest sorptivities; (iii) The sorptivities of the 1:3 mortar were approximately similar to those of the 1:2:4 concrete, but the 1: 5 mortar showed much higher sorptivities. The sorptivities of the 1: 1: 5 mortar were lower than those of the 1: 5 mortar, but higher than those of the 1: 3 mortar.