Development of sustainable ternary cementitious binder with OPC integrating calcined clay and LF slag

Abstract

Pursuit to sustainable cementitious binders, application of supplementary cementitious materials (SCMs)/waste materials is increasing day by day. In the current article, OPC was partially substituted with alternative resource materials e.g., processed ladle furnace (LF) slag and calcined clay in fabricating a ternary binder. Performance of developed ternary binder was examined with respect to hydration, mechanical characteristics, phase analysis, microstructural behaviour and durability. Optimised ternary binder paste (50% OPC, 30% calcined clay and 20% Processed LF slag) demonstrated excellent mechanical properties. The optimised paste showed highest peak intensity of calcium silicate hydrate and calcium alumino-silicate hydrate in the mineralogical study, which was further validated by micro-structural studies. Hydration studies showed more cumulative heat flow (95 J/g) in optimised binder than other binders. Performance of optimised binder paste with respect to durability, which includes water absorption, porosity and drying shrinkage, was comparable with OPC. Whereas the performance of optimised ternary mix under chloride and sulphate exposure was found better than OPC. This route of developing ternary binder as sustainable alternative to OPC will definitely fulfil the commitment towards net zero emissions by 2050.