Abstract: Samples, with slurry concentrations of 78%, 80% and 83%, cement-tailing ratios of 1∶6, 1∶8, 1∶10, 1∶15, 1∶20, 1∶25 and 1∶30 and different curing time, were prepared by using the neutralized uranium tailings from heap leaching as the aggregate, and the uniaxial compressive strengths for the samples were measured. The relationships between the cemented tailings strength and the curing time were established by experimental data fitting. The results showed that the mechanical parameters for the relationships, such as final strength of cemented tailings, strength response factor, time needed for strength stability and primary strength (t=3) can quantitatively describe the variation of the cemented tailings strength over the curing time. Energy match coefficient was proposed to show the energy density relationship between the excavation and the backfill deformation. Calculation equation showed that the reasonable match time correlated closely with volume density of rock mass, depth of the ore body, elastic modulus of rock mass, cement-tailing ratio, slurry concentration and curing time. This new approach was verified by a uranium mine.

Key words: cemented tailings backfill, energy accumulation for backfill, energy release from excavation, match characteristics