Optimization of Cable Bolting Installation for the HW of an Open Stope
Cable bolting the HW of relatively shallow dipping open stopes is a common practice for the support of underground openings. This helps control dilution (thus reducing cost) and increases stopes turnover. The purpose of this example is to demonstrate the effect of cable bolting on the stability of an open stope’s hanging-wall (HW) in a blocky ground and how to improve a given cable bolting pattern.
Behavior of a Shear Zone (fault) Adjacent to UG Mining Excavations and its Implication on Mine Planning
Most of underground or open pit mines have geological discontinuities including major faults and shear zones that could impact the mining sequence, recovery and ground control designs. This example shows that fault-slip analysis is sensitive to the orientation and magnitude of far field stresses, as well as the geometry and the geotechnical properties of the shear zone.
Design of Ground Support System for an Overcut in a Cut and Fill Operation at Depth (Part 1 of 2)
Cut and fill mining method is the preferred choice for steeply dipping, irregular, thin and relatively high grade orebodies. As the underhand and overhand cuts approach each other, the diminishing pillar, referred to as ‘sill pillar’ is subject to increasing stresses. Therefore, the last planned overcut is usually subject to high stresses in the back, making it a difficult cut to mine from a production rate and workers safety standpoints.
Design of Ground Support System for an Overcut in a Cut and Fill Operation at Depth (Part 2 of 2)
In this section, we will contemplate how to use modeling results of part 1 into the design of ground support of the overcut. Dynamic calculations (energy release and bolt energy absorption) are addressed along with selection of surface and bolt support.
Determination of Backfill Strength Requirements in Underground Stopes with an Open Face
In this example, the backfill strength required for safe extraction of adjacent blocks and to minimize backfill dilution can be determined from numerical modelling with FLAC3D. The same type of exercise can be used to determine what is the required ground support for remnant mining strategies or to mine underneath or around a placed backfill with a given strength.