Title: Studies on the Desiccation and Carbonation of Systems Containing Portland Cement and Fly Ash

Author(s): F.G. Buttler, M.H. Decter, and G.R. Smith

Publication: Symposium Paper

Volume: 79

Issue:

Appears on pages(s): 367-382

Keywords: carbonation; compressive strength; curing; drying; fly . ash; mortars (material); portland cements.

DOI: 10.14359/6702

Date: 5/1/1983

Abstract:
Cement:sand mortar cubes, some containing fly ash, have been subjected to a number of curing regimes involving desiccation and carbonation using a high-partial pressure of carbon dioxide. The compressive strengths of the cubes were determined without fracturing them by applying an increasing axial load whilst the lateral strain on the cubes was monitored continuously. After the compressive strengths had been determined the cubes were sectioned and each section analysed for calcium hydroxide and carbonate content. The results show that, following curing at 20°C only and particularly when the pozzolanic reaction of the fly ash was restricted by desiccation, the cubes containing fly ash carbonated more readily than cpmparable ones in which fly ash was absent. With higher water contents and with non-desiccated cubes those containing fly ash performed in a similar way to those that did not.