Title: Performance Evaluation of Set Accelerators For Concrete

Author(s): A. A. Jeknavorian, N. S. Berke, and D. F. Shen

Publication: Symposium Paper

Volume: 148

Issue:

Appears on pages(s): 385-406

Keywords: accelerating agents; air-entraining agents; corrosion; cold weather construction; inorganic salts; setting (hardening); strength; Materials Research

DOI: 10.14359/4113

Date: 9/1/1994

Abstract:
Among the requirements for Type C and E accelerators in the ASTM C 494 Specification on Admixtures, limits for set and strength performance are stipulated for concrete mixed and cured at 23 C (73 F). However, set-accelerating admixtures are predominantly used for cold weather concreting operations, where they can significantly increase the rate of early strength development at low temperatures, thereby reducing the curing and protection periods necessary to achieve specified strength. Paper discusses a laboratory program designed to evaluate the effectiveness of various set-accelerating admixture formulations. The scope of the program includes measuring set, strength, and air-entraining performance over a wide range of mix and curing conditions, and selection of cementitious materials. Furthermore, considering that a wide range of soluble inorganic salts, used over a relatively large dosage range, has been shown to accelerate the setting early hardening of portland cement, protocol for evaluating the corrosive potential of accelerator formulations containing these salts is discussed.