Title: Rapid Hardening Cements for Repair of Concrete

Author(s): Sandor Popovics, N. Rajendran, and Michael Penko

Publication: Materials Journal

Volume: 84

Issue: 1

Appears on pages(s): 64-73

Keywords: cement pastes; compressive strength; concretes; electron microscopes; heat of hydration; high early strength cements; hydration; infrared spectroscopy; magnesium; mortars (material); portland cements; regulated set cements; repairs; setting time; strength

DOI: 10.14359/15163

Date: 1/1/1987

Abstract:
This paper presents the results of an investigation on very rapidly hardening cements. Rapid hardening cements are those that can develop several thousand psi compressive strength within a few hours. Since these cements were developed just recently, very little laboratory and even less practical experience have been obtained with them. Therefore, this paper presents the results of a laboratory investigation on four such cements. These cements are: 1. magnesium phosphate cement for cold and regular weather use (MPC); 2. magnesium phosphate cement for hot weather use (MPH); 3. aluminum phosphate cement (MAP); and 4. regulated set cement (RS). A combination of both mechanical and physicochemical tests ere performed. Several chemical admixtures were also tried with these cements. The tests revealed that the magnesium phosphate base cements exhibit the most rapid strength development. The presented investigation concentrates on the strength development at early ages. Other important properties of these mixtures (durability, etc.) will be present in another paper.