Research Information System
Recycling and Reuse of Waste Materials, Proceedings of the International Symposium, Dundee, United Kingdom, 9 - 11 September 2003, pp.475-484, (Full Text)
The rheology of a suspension is always a function of "Fluid Phase Rheology". The rheology of concrete can therefore never be optimal if the rheology of the concrete fluid phase (cement-water-additive) is not optimal. To reach the optimum mix design for Self-Compacting Concrete, it is important to find out the right combination of cement and filler material, both amount and type. The replacement of cement by mineral additives strongly influences the flow resistance; it may improve or worsen the workability. The successful utilization of quarry dust in self-levelling cement pastes could turn this waste material into a valuable resource. The effect of cement replacements with three types of limestone powders produced from different quarries on the rheology of the fresh paste has been studied in this research. Also the mechanical and drying shrinkage properties of paste in the hardened state has been investigated. A 10 percent replacement of cement with a special type of quarry dust was found to lead the best performance at fresh state rheological properties and at hardened state compressive strengths. All filler additions decreased the drying shrinkage of cement pastes at different orders when compared with pure cement paste specimens. The positive effects of quarry dust on fresh and hardened properties of self-levelling binders make this material a feasible additive besides its economical and environmental advantages.