Optimization of Grading of Sand in Backfill Using Metallurgical Waste
T. I. Rubashkina, M. A. Korneichuk
Belgorod State University, Belgorod, 308015 Russia
Keywords: Cemented backfill, blast-furnace granular slag screenings, aggregate grading, cemented backfill strength, backfill flowability
Abstract
It is technologically and economically advisable to optimize grading of low-quality fine and very fine sand with increased content of clay and dust particles used in preparation of cemented backfill mixtures by adding blast-furnace granular slag screenings 0-5 mm in size without preliminary treatment. The relationships of the size modulus, specific grain area and clay/dust particle content of sand and the percentage of slag in the composite aggregate are obtained. It is found that with increasing percentage of slag in the composite aggregate, water demand lowers owing to the higher size modulus of the aggregate and due to the decreased content of clay particles in it. This allows production of cemented backfill mixtures at the decreased consumption of cement while the strength and flowability of the mixtures are preserved.
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