Mining in focus
An underground surveyor in action .
Nicolaas Steenkamp safety department ’ s planning and preventative or proactive measures . The maps are crucial for proto-teams and mine rescue in the event of an incident rescue and / or recovery operation . Accurate maps are lifesavers when emergency ventilation or communication and supply boreholes need to be drilled .
Surface mine surveying
In surface operations , the mine survey data will determine the development of the open pit . The data is used by the rock engineers and geotechnical engineers to identify potential risks , such as slope failure , by monitoring slow movements or deformation as detected by the mine survey . The data is also used to determine the risk of encountering failures due to , for example , wedges being exposed by excavations . The mine survey data is also used to determine the rate of development of the open pit and the remaining resources and reserves , based on the pit-shell model . Whittle optimisation can be applied to increase or decrease the size of the pit-shell , using the survey data . Other surface survey tasks are related to surface layouts , which will include buildings and other permanent or temporary structures . Surface surveys are also used to measure stockpiles .
The maps generated for a surface mining operation are a representation
of the true size and shape of all excavations . The map should contain sufficient cross-sections showing the advances made in the operation and the areas reclaimed or again filled in .
3-D scanning surveys
The introduction of laser 3-D scan has revolutionised the mine surveying industry . Mine surveys can now be completed in a fraction of the time of a traditional survey by a suitably qualified surveyor . The laser 3-D scans can be viewed interactively and give a much richer texture and level of detail . The 3-D model has the option of a ‘ fly-through ’ view and offers detail as small as nuts and bolts . Incident investigations will also benefit greatly from this advance in surveying , offering 3-D views that can be used by the incident investigation team , without the risk of disturbing the scene or placing more people at risk by entering the danger area . The data can also be used to reconstruct the event or to run simulations .
Laser survey scanners are able to capture large amounts of data in a point cloud . This data is then used to create a CAD model . The latest technology can capture a large number of points ( approximately 976 000 per second ), accurately and quickly . Buildings , industrial plants , and mine voids can be scanned and models constructed of the ‘ as built ’ conditions .
Drones
The increasing commercial availability of drone or unmanned aerial vehicles ( UAV ) has also had a major impact on the mine surveying industry . Drone-based data collection aids in increasing productivity by reducing the amount of time needed to conduct a survey and minimising the amount of time required to mobilise from one survey position to the next . It also reduces the reliance on images collected by third parties and is significantly cheaper than conventional aerial photography from an aeroplane or helicopter .
Surveyors are able to collect accurate spatial data from the air using a drone or UAV technology and can vastly reduce risk by minimising the time staff spend on site . The drones can also be used to survey risky areas within active open pits or dangerous slopes . The main limitation in South Africa on the use of UAVs or drones is that pilot licences are required to operate it legally .
Work is also being done to effectively use drones in underground operations . In parallel , work is being done to develop automated or semi-autonomous vehicles to conduct surveys . Both technologies will reduce the risk , especially in dangerous areas . b
[ 26 ] MINING MIRROR APRIL 2018