Strength and energy dissipation of whole tailings cemented backfill body

The strength of backfill body is a crucial parameter in backfilling mining, and the failure process of cemented backfill body is essentially an energy dissipation process. To investigate the effects of curing age and cement-sand ratio on the strength and energy consumption of backfill, whole tailings were used as aggregate to prepare slurry with mass concentration of 74%, and the slurry with cement-sand ratio of 1:4, 1:6, 1:8 and 1:12 was poured into backfill. Uniaxial compression tests were conducted on backfill body specimens that had been cured for 7 days, 14 days, 28 days, and 45 days. It aims at studying the compressive strength, damage, energy storage limit, energy dissipation, and crack propagation of the fill. The results show that when the cement-sand ratio is held constant, the strength of the backfill increases with curing age. Simultaneously, when the curing age is fixed, the strength is positively correlated with the cement-sand ratio. During uniaxial compression tests, it is observed that the pre-peak energy consumption, post-peak energy consumption, total energy consumption, and unit volume strain energy of the cemented backfill body exhibit exponential relationships with both curing age and cement-sand ratio. The energy storage limit of the backfill reflects its capacity to absorb energy prior to failure, while the relationship between damage and energy consumption provides an accurate depiction of its internal failure mechanisms at different stages. In the failure process of the cemented backfill body, primary cracks accompany secondary cracks, many microcracks initiate and propagate from the stress direction, and crack propagation consumes a significant amount of energy. This study on the strength, energy storage limit, and failure of the cemented backfill body can provide valuable insights for mine safety production.