Title:
Grout for Post-Tensioning Ducts
Author(s):
Brian B. Hope and Alan K. C. Ip
Publication:
Materials Journal
Volume:
85
Issue:
4
Appears on pages(s):
234-240
Keywords:
corrosion resistance; ducts; evaluation; grout; grouting; post-tensioning; prestressing steels; Materials Research
DOI:
10.14359/2075
Date:
7/1/1988
Abstract:
The purpose of this study was to improve the present grout formulation used by the Ontario Ministry of Transportation and Communications and to examine the current grouting procedure for the post-tensioned structures. A test program was carried out to evaluate various types of grout mixtures. During the initial screening stage, flow time, expansion, bleeding characteristics, viscosity, compressive strength, absorption, density, and pH of the test grouts were examined. In the final evaluation stage, electrical resistivity, chloride permeability, and corrosion susceptibility of the most promising grout mixtures were evaluated. The most promising grout formulation was found to be a combination of CSA Type 10 (ASTM Type I) cement, silica fume, aluminum powder, and superplasticizer. Recommendations for improving field procedures include premixing the dry grout ingredients before use in the field and introducing flow time measurement as a means of control.