Title: The Use of Chemical Admixtures to Facilitate Placement of Concrete at Freezing Temperatures

Author(s): S. A. Farrington and B. J. Christensen

Publication: Symposium Paper

Volume: 217

Issue:

Appears on pages(s): 71-86

Keywords: accelerating admixture; chemical admixture; cold weather concrete; compressive strength; high-range water reducing admixture; low temperature; water reducing admixture

DOI: 10.14359/12906

Date: 9/1/2003

Abstract:
Concrete that is to be placed under cold weather conditions must be protected from freezing and may be required to have adequate setting behavior and strength development. There are a number of different approaches that can be used to ensure protection from freezing and the development of mechanical properties of such concrete. One approach is the addition of chemical admixtures that accelerate the cement hydration in the concrete. This paper presents the results of studies that examined the performance of a new cold weather admixture (CWA). The performance of the CWA was evaluated in concrete with an initial concrete temperature of 11-13°C that was cured at an air temperature of either -1 °C, -7°C, or -11 °C. The addition of the CWA allowed the concrete to set and gain strength under the cold weather conditions. Lowering the w/c of the concrete with a high-range water reducing admixture coupled with the addition of the CWA further improved the setting and strength development of the concrete at the lowest curing temperature tested. These results suggest that the use of the CWA will allow current cold weather concreting guidelines to be revised to allow for lower initial concrete temperatures.