Simply Empowering: Innovative Software Tools for the Miner
"Simplicity is the ultimate sophistication."
Leonardo da Vinci (the draftsman, painter, sculptor, architect and engineer)
Introduction:
Today, Canadian mines face stern challenges. Many confront dwindling ore reserves, or remaining inventories that lie at great depths. All operate under strict regulations that require responsible environmental behaviour, and all have to compete with lower cost operations based in developing countries.
Under such operating climates, success demands engineering excellence. Rocscience Inc. develops innovative software tools that facilitate such excellence in geomechanics. This paper will describe the use of two simple-to-use, yet powerful programs – Examine3D and Phase2 – that enable engineers to design underground mine openings.
Simple Can Be Powerful:
Rocscience supplies the mining industry with high quality, cutting-edge software tools for analyzing structural data on rock masses, and for designing safe and economical mine openings. The greatest strength of our programs lies in simple, efficient interfaces underlain by powerful, sophisticated analysis routines. This enables engineers to channel creative energies into solving geomechanics problems, rather than into figuring out software quirks.
Examine3D and Phase2 are both numerical modelling programs for calculating stresses and deformations around excavations. The principal difference between the two is that Examine3D is for three-dimensional, elastic analysis, while Phase2 performs two-dimensional, elasto-plastic analysis. The programs complement each other, however.
When modelling the entire layout of an underground mine (generally to understand global stress behaviour), Examine3D is the tool of choice. It accommodates the large geometric extents of such problems, and is able to capture stress interactions caused by the three-dimensional geometric layout of openings. A case study, describing how Examine3D was used to design a de-stress slot at an Ontario mine, will be presented in the paper. The main shaft was experiencing dangerously high stresses. Examine3D was used to select a shape and location for the slot that reduced stresses around the shaft, and also allowed high-grade ore to be extracted from a highly stressed pillar near the shaft.
Combining sophisticated analytical capabilities with a user-friendly interface, Phase2 can be used to model the two-dimensional behaviour of excavations and slopes, including complex problems in weak rock and soil. The program is well suited for conditions dominated by material failure. It supplies tools for modelling excavation support systems, discontinuities, seismic loads, and for staging excavation sequences.
Phase2 was used in the de-stress project to design the properties of backfill for the slot. Examine3D modelling revealed that the slot’s thickness, and the stiffness of its backfill material, would play critical roles in lowering stresses in the desired zones. This discounted an initial plan of creating the slot using overlapped boreholes. Phase2 analysis then showed that a second approach of excavating the slot through blasting, and backfilling it with broken rock, would also not work. The program helped design engineers to obtain more complete knowledge on the contribution of backfill stiffness to stress redistributions.
Concluding Remarks:
Overall, the paper will demonstrate that packaging essential geomechanics design capabilities into simple-to-use software facilitates good engineering. Such programs are empowering.
