OPEN CUT MINING

Review of blast designs through field assessment and modelling remains a common component of the Heilig & Partners consulting expertise. Outcomes of these studies may focus on issues of improving wall stability of large open cut mines through to quarry faces, optimising fragmentation and diggability of the blasted rock through to improving the overall economics of the drilling and blasting process.

Optimisation of the open cut blasting process with respect to controlling the environmental impacts is routinely provided advice. Models to investigate the influence of varying blasthole patterns, bench heights, blasthole diameters, uncharged collar lengths and explosive types and densities on the level of fragmentation are also available to clients of Heilig & Partners.

Prediction of vibration and overpressure levels from different blasting configurations can also be undertaken. Estimating safe exclusion zones on the basis of flyrock control can be undertaken using sophisticated models based upon NASA code and numerous other technically reviewed models applied in the blasting industry.

Highlighting areas of the open cut mine where restricted blast designs and mining configurations may be necessary to ensure compliance can be assessed through the many analytical models available. Specific “near field” models can be used to optimise wall control blasting, in particular identifying appropriate blasthole loading configurations for pre-split, trim blast and production blast designs.