In recent years number of organization in Europe have become increasingly involved in research aimed at energy conservation in the cement and concrete industry. This, in part, is being accomplished by encouraging the use of cementitious materials such as fly ash, slag and pozzolans. Lately, some attention has been given to the use of the pozzolans, silica fume, as a possible partial replacement for portland cement. Certainly, that our earth planet is subjected to pollution hazards as a result of the advance of technology in metalurgical industries, for instance, in Egypt, It is found, the Egyptian ferroalloys and Egyptian Iron and steel companies ( Edfu-Aswan & Helwan) they suffer from bounteous of silica fume and granulated blast furnace slag successively. Thereby the accumulation of silica fume and slag every year in these plants without being used represents not only a significant loss of money and energy by occupying a big area from these plants but also a negative impact to the environment. This paper studied the usage of granulated blast-furnace slag as a ground material (% passing from size # 45um = 0.85 %, i. e. specific surface area = 2500 cm 2 I gram) with combination of silica fume in cement paste and mortar mixtures as a partial replacement for cement. This study shows that with increasing the silica fume percentage and decreasing the GGBF slag percentage, the water demand to produce the standard consistence of cement paste is sharply increased and the initial and final setting times of the paste mixtures reduced." |
