Development of ternary blended Concrete

Abstract

Manufacturing of Portland cement is an energy intensive process newlineand releases very large amount of green house gases into the atmosphere newlinewhich affect the earth s ecosystem Efforts are being carried out to conserve newlineenergy by means of promoting the use of industrial wastes or by products newlinesuch as Fly Ash FA Ground Granulated Blast Furnace Slag GGBS Silica newlineFume SF Rice Husk Ash RHA etc which contain amorphous silica in its newlinechemical composition as mineral admixture for partial replacement of newlinecement In India the thermal power plants produce more than 100 million newlinetonnes of FA every year Apart from this large quantity of RHA is also newlinegenerated from the agricultural sector These by products develop serious newlineenvironmental problems if not utilized properly The partial replacement of newlinecement by these by products reduces the production cost of concrete and also newlineaddition of FA RHA with cement has beneficial effect on workability heat newlineof hydration and permeability of concrete The addition of admixtures not newlineonly improves the impermeability but also acts as scavengers for penetration newlineof chloride ions which prevents corrosion of embedded rebar in the concrete newlineHowever reduction of the compressive strength of concrete flexural strength newlineof concrete at the early ages and increasing carbonation of concrete are found newlineto be major drawbacks in the FA based blended concrete The early age newlinestrength development and setting time of concrete are important parameters newlinefor quick removal of formworks newline newline