Mine Instrumentation/ Tambang
PROJECT MANAGERS, DESIGNERS, CONTRACTORS AND OPERATORS ALL AGREE UPON THE NEED FOR WELL-PLANNED MONITORING, ADAPTED TO EACH INDIVIDUAL EXCAVATION.
Monitoring plays an important role in every stage of a mine exploration and operation. It is used to accurately
assess geological conditions and quantify certain parameters over time as well as monitoring their rate
- At the design phase the use of testing equipment (laboratory or In-Situ) can determine the geotechnical characteristics of an ore body and surrounding rock mass.
- Monitoring is used to accurately evaluate the geological conditions as the excavation progresses. Design hypotheses can be confirmed, the needs of the support structures defi ned and the optimum moment for instrument installation in accordance with convergence-confi nement (NATM) methods can be determined.
- Once the underground mine is in service, long-term monitoring ensures the safety of the access shaft gallery operation over its life span.
In the case of an open pit, as the excavation progresses, the slope stability could be affected creating potential failure. It is therefore necessary to closely observe its beha viour and monitor over time. Auxiliary structures such as tailing impoundments require a thorough assessment as well as continuous monitoring and control during sitting, construction and operation of the mine to insure the prevention of environmental disasters. Well-planned and implemented monitoring is an essential component of successful mine construction and operation. Mine monitoring is subject to numerous regulations in many countries and this is adhered by strict administrative standards.
Selection Criteria for Instrumentation
Four major criteria guide instrument selection:
- Reliability of the measurements obtained (accuracy, resolution, precision and drift)
- Longevity of the instruments supported by numerous references
- Ease of readout automation, essential for effi cient data collection and interpretation
- Features of some instruments like their immunity to electromagnetic interferences and
their intrinsically safe technology for coal mine application Roctest Telemac mine monitoring instruments respond precisely to these four criteria. Monitoring involves numerous steps including direct or remote visual inspection as well as topographical measuring and instrumentation. The scope of the monitoring methods employed depends on the potential risk associated with mine and site characteristics.
- Gallery geological conditions
- Access shaft structural behaviour
- Excavation and tailing impoundment stability
Automated Data Acquisition and Processing
The collection and analysis of large quantities of data, especially over long distances, requires centralized and automated measuring techniques. Results are more accurate and data can be processed more rapidly thus enabling effi cient alarm systems to be implemented when predetermined thresholds are exceeded. It is practically impossible to consider the instrumentation of a major excavation without automated data acquisition systems. Roctest Telemac’s SENSLOG allows economical data logging and can be readily connected to multi-node networks for real-time monitoring. Data acquisition centers are easily user-confi gured through a high-level “soft” instrument control language. This language supports full diversity in connected device types, measurement intervals, data conversion, statistical processing, strategies for alarm control and logging.
- Ensure stability of excavation walls
- Monitor the integrity of adjacent structures, if applicable
- Load in anchors
- Lateral and vertical movement of the surrounding
- Ensure the stability of the excavations
- Monitor the integrity of the gallery
- Deformation of the rock mass around the excavation
- Stress of rock mass
- Verify general stability of structure
- Ensure that infi ltration does not create internal erosion (piping) which may have sliding effects or cause rupture
- Pore pressure within the foundation
- Seepage fl ow through fi llers and drains
- Total and differential deformation
- Lateral and vertical movement