* Foam reduces and in most cases eliminates segregation of the solids/water in high density backfills during transport
This offers great potential for backfill surface tailings disposal.
conveyor places material in a hopper that travels the length of the conveyor and is returned to the trench on a cross conveyor.
Underground paste backfill has become well established in the Canadian mining industry over the last several years as a proven, cost-effective, high quality alternative to rock fill and hydraulic slurry backfill.
Golder Associates has been a leader in implementation of paste technology as a preferred solution to backfill placement and surface waste disposal.
The potential for chemical incompatibility between backfills and the contaminated groundwater is a crucial consideration for vertical cutoff walls, which results in an increase in k.
However, PAC-amended bentonite or sand-bentonite backfills used in hydraulic barrier applications has not been reported.
In past, before the mine closure works had approved, extensive numerical models were done by checked, proposed, grouted, and other consolidation measures supported by laboratory and in situ investigations in the goal to determine the geotechnical characteristics of rock mass and backfills.
Time-dependent occurrences of potential sliding areas on the surface and in mine rocks and subsidence of artificial backfills are still present, but the intensity of time-dependant movements is considerably reduced.
As shown in the comparison of the effects of mining on the overlying strata in six different width mines in Figure 7, the maximum convergence displacement of the roof gradually increases with the reduction in the proportion and concentration of backfills
, but the difference is insignificant.
Caption: Figure 3: Visual appearance of cemented backfill
bodies at 360 d.
Due to the advantage of removing the underground goaf hazards and preventing surface subsidence, the backfill
mining method is widely used in complicated mining conditions, for example, mining under bodies of water, railways or highways, and buildings [3-5] (Table 1).