Selection of Frozen Backfill Mixture Composition

Artificial frozen backfill for coal and ore mines in permafrost zone is discussed. Optimal frozen mixtures with the required strength characteristics are determined. It is shown that load-bearing capacity of backfill depends on grain size composition and volumetric content of ice. The mathematical model of layer-by-layer backfilling is developed, and the freezing time is found. Varying mixture composition and freezing parameters allows arriving at the required strength of frozen backfill at minimal filling time.