Abstract
Predictive blasting models are being used to optimise outcomes in many areas of the value chain. This paper will concentrate on surface, hard rock, blast movement models used in grade control and extraction operations.
Physics models have come a long way since computer modelling began. Computer gaming engines and the acceleration of graphics processing units have enabled enormous computational power that is being used to quickly simulate millions or billions of particle interactions.
Today, extremely complex physics models are used to simulate the effects of blasting in a variety of situations. One blast movement modelling program has been used by hundreds of mines globally, simulating over 50,000 blasts. The accuracy of the simulations created by this program depend on many factors, but principally, on the quality of the blast design data imported into the simulation. Other items matter, such as the pre-blast boundary conditions, actual hole firing times, and rock mass properties. But the simulation stands no chance of an accurate outcome if the blast design imported is wildly different than the actual blast design implemented.
Some variation between a blast design and the as-built blast design is expected. Many studies have shown improvements in the accuracy of hole drilling, benefits to properly loading holes, and better fragmentation through precise electronic initiation systems. Several products exist in the marketplace that allow miners to measure and record as-built blast data and compare it to the blast design. However, the effects of the variation between planned and as-built on grade control financial outcomes has been largely ignored. With this knowledge, miners may be able to understand what as-built data is critical, and what data is “nice to have” if available.
This paper will present actual blasts simulated with a blast movement model, and the incremental improvements gained through more accurate and precise blasting data.