Workability and Compressive Strength Properties of (Fly Ash-Metakaolin) based Flowable Geopolymer Mortar

Abstract

RPC (Reactive Powder Concrete) is a high-strength concrete with outstanding technical qualities. One of the most crucial critical criteria in RPC development is the cement content. Cement production is seen as an environmentally unsustainable process. As a result, it is necessary to substitute cement in RPC manufacturing with an environmentally acceptable binder. Geopolymer seems to be a novel binder that can completely replace cement. The properties of constituents and their percentages in the mix significantly affect the behavior of geopolymer concrete or mortar. This research aims to produce Geopolymer RPC (GRPC) and verify the impact of the ratios of fly ash/pozzolanic materials (FA/P), sand/pozzolanic materials(S/P), finer sand/fine aggregate (S2/S1), and alkaline solution/pozzolanic materials (A/P) on its mechanical and durability properties. The results of the current works demonstrate that increase in alkaline solution to binder ratio increase the compressive strength of the mortars from 62.28 to 70.01 MPa at 62.50% to 100% alkaline/binder ratio, respectively. As well as, vfor the same alkaline/binder ratio the workability subsequently improves from 15 to 17.3mm.