The effects of Feldspar and GGBS on the mechanical properties of the mortars

This experimental study investigates the effects of substituting cement with Feldspar and Ground Granulated Blast-furnace Slag (GGBS) on the mechanical characteristics of mortars. Prior research has studied the use of Feldspar as a cement substitute. In this work, however, GGBS has been added to Feldspar to evaluate the mechanical properties of specimens. Cement was partially replaced with Feldspar and GGBS at ۱۰%, ۲۰%, and ۳۰% replacement rates. In general, two sets of ۲۰ mix designs with w/b ratios of ۰.۴۰ and ۰.۳۵ were investigated. For evaluation of mechanical qualities, compressive strengths after ۷, ۲۸, and ۹۰ days of curing and flexural strengths after ۲۸ and ۹۰ days were obtained. In all mixes containing Feldspar and GGBS with varying w/b ratios, mechanical properties were slightly reduced by Feldspar and GGBS replacement, with the exception of ternary mixes, which exhibited divergent trends; mixes containing GGBS exhibited higher mechanical properties than mixes containing Feldspar. In addition, mixtures with a w/b ratio of ۰.۳۵ had better outcomes than those with a w/b ratio of ۰.۴۰.