Durability of an Arctic Concrete

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Durability of an Arctic Concrete

Author(s): Micheline RegourdI

Publication: Special Publication

Volume: 100

Issue:

Appears on pages(s): 919-935

Keywords: aggregates; chlorides; compressive strength; concrete durability; low temperature; sulfates; sulfides; General

Date: 4/1/1987

Abstract:
The use of unconventional aggregates, which includes several sulfide minerals, in making concrete in the Canadian Arctic aroused the interest of the authors to investigate the durability of such a concrete subjected to a very cold environment. Compressive strength measurements on concrete samples three and nine years old, cored in a dock, show that the concrete is still very strong--at least 28 MPa (4000 psi). A close examination of the aggregates and concrete microstructure suggests the concrete is durable. The presence of these aggregates does not give rise to any deleterious effect. The concrete is found to be a dense one. Only a superficial layer of a few millimeters thick has been transformed by carbonation. This zone, enriched in potassium, does not contain any Ca(OH)2 crystal. Its C-S-H has a low CaO/SiO2 ratio and is sometimes replaced by a siliceous gel. Penetration of chloride and sulfate ions is also observed but is not related to any concrete damage. The presence of a large amount of Ca(OH)2 and calcium rich C-S-H (C/S ÷ 1.7) below the thin carbonated layer corresponds to a high chemical stability of the concrete.