Title: Effect of Supplementary Cementitious Materials on Rheological Properties, Bleeding, and Strength of Structural Grout
Author(s): K. H. Khayat, A. Yahia, and M. Sayed
Publication: Materials Journal
Appears on pages(s): 585-593
Keywords: admixtures; adsorption; bleeding; grout; rheology
Cement grouts used for crack injection, anchorage sealing, and post-tensioning applications are proportioned to exhibit high flowability to facilitate casting and adequate cohesion to prevent phase separation and bleeding. An experimental investigation was carried out to evaluate the effect of different types of supplementary cementitious materials (SCMs) on rheological properties, stability, and compressive strength of structural grout. Substitutions of cement by 3% silica fume, 10 to 30% Class F fly ash, and 40% granulated blast-furnace slag were considered. Various binary systems that resulted in good performance were also combined to investigate the effect of ternary cement blends on grout performance. The use of SCMs in structural grouts is shown to increase water demand in mixtures made with portland cement. When incorporated in well-dispersed systems, the use of binary and ternary cements led to higher fluidity, lower yield stress, higher plastic viscosity, and greater resistance to forced bleeding compared with reference mixtures made with portland cement. This paper discusses the performance of various grout mixtures prepared with binary and ternary binders and different concentrations of high-range waterreducing admixture.