SLOPE STABILITY MONITORING
Movement Analysis , a solution that they say goes beyond standard analysis of tailing dams . It incorporates the new Guardian algorithm developed in cooperation with Geopraevent , which “ plays an important role for early precursors of potentially catastrophic tailing dams failures .”
To reliably monitor slow movements over several months or even years is very challenging especially on fixed , but vegetated slopes such as tailing dams , where the smallest movement can be a precursor of a slope failure . SLYX measures very slow displacements with “ an unprecedented coherence ” in the resulting data . The algorithm is based on an automatic selection of the most suitable measurements from the IBIS radar data and on a tailored evaluation for slow movements . This procedure gets even closer to the detection limits , accurately determining millimetre movements over extended time periods .
SLYX is integrated in IBIS Guardian with a dedicated interface for easier application . The analysis period and the measurement window for analysis are flexible and can be selected by each user . “ The reliable and accurate measurement of small , slow movements is difficult . With SLYX Slow Movement Analysis , we launch a powerful tool that allows us to do just that . The SLYX algorithms make it possible to detect large-scale mm movements over several days to months that would normally be lost in instrumental noise ,” said Lorenz Meier , Geopraevent CEO .
Francesco Coppi , IDS GeoRadar Director of Monitoring Radar Product Management , commented : “ Slow movements play an important role as early precursors for potentially catastrophic slope failures , as it could happen for tailing dams . SLYX represents a game changer in this field .”
Senceive on intelligent wireless remote monitoring
Wireless remote condition monitoring is used in a variety of mine applications , but it is especially well-suited to slope monitoring , mainly on open pit walls and tailings dams . UK-based Senceive has been providing users with wireless monitoring solutions since 2005 and the technology is well-proven in demanding conditions . Mine operators can benefit from precise , regular updates on gradual movement such as deformation or sudden failures such as landslides .
Marketing Director Simon Brightwell told IM : “ The technology is ideal for remote locations with limited power and communications infrastructure . All elements are rugged and suitable for long-life performance in all types of climatic condition likely to be encountered .
Senceive solution for Mt Carlton
Evolution Mining ’ s Mt Carlton gold mine is 150 km south of Townsville , Queensland . Operating a 500 m by 400 m pit and a 600 m by 600 m tailings dam , the company opted to introduce advanced deformation monitoring technology to deliver real-time status updates and alerts to its team . Evolution opted for Senceive ’ s GeoWAN solution , a long-range transmission system capable of covering a distance up to 15 km . It incorporates several sensors placed along the tailings dam and / or pit walls to measure for minute movements in the surface . The sensors are wirelessly connected to a solar powered gateway , positioned near to the pit , where data is transferred live to the web-based monitoring software . Depending on the application , different sensors can be used in combination to deliver highly accurate geotechnical measurements , including tilt , pressure , vibration , temperature or optical displacement . Technical support and product training was provided by Senceive ’ s Australian based distributor , Position Partners . The Position Partners deformation monitoring team offers comprehensive advice , installation , onboarding and support throughout Australia , New Zealand and South East Asia . At Mt Carlton , Evolution has more than 20 triaxial tilt sensors positioned around the tailings dam to measure for any movement . The team is also rolling out live monitoring of piezometers that measure changes moisture levels within the tailings dam walls . In the open pit , there are numerous sensors monitoring pit wall , waste backfill and survey pillar movement . Senior Mine Surveyor for Evolution , Callum McNaughton , said the solution has enabled his small team to provide accurate , viable monitoring data to the departments that need it . “ The wireless monitoring platform has been perfect for us ,” he said . “ It dramatically reduces the need for us to manually survey these areas , saving us time and increasing safety by removing surveyors walking these areas on foot .” One of the key advantages , McNaughton explains , is the ability to set different tolerances and time triggers for each sensor and / or area . “ In the tailings dam we have a slightly higher tolerance before any alerts are triggered , because you do get some
Evolution opted for Senceive ’ s GeoWAN solution at Mt Carlton movement in the dam and swelling from rain ,” he said . “ Inside the pit and in one area where there is a crack in the wall , the tolerance is much tighter and the sensors are triggered more frequently ,” he added . “ The sensors are also firing measurements every 10 minutes in the pit , whereas they monitor every half an hour on the tailings dam .” The monitoring data is used by multiple teams at Evolution Mining , including surveyors , geotechnical engineers , pit supervisors and the control room . “ We can configure who gets the alerts and the escalation process , so that different teams can receive different levels of alert if need be ,” McNaughton said . In addition to alerts if movement outside of tolerance is detected , the team uses the monitoring information for various reporting requirements . Geotechnical and survey teams use the data in their monthly reports , and it also forms part of the company ’ s quarterly compliance report for the tailings dam . “ It ’ s great that the monitoring data is helpful to so many different stakeholders at Evolution ,” McNaughton said . “ The geotechnical engineers can pull out any relevant information for their reports and dashboards , and the pit supervisors can instantly receive any alerts if there are changes detected by the system .” McNaughton said that the wireless monitoring system did not replace traditional survey methods , but instead complimented them with ongoing monitoring data that enables early intervention and proactive management of the pit and tailings dam .
Networks are engineered to have a degree of self-healing in order to withstand damage to indvidual components . Sensors are installed in
minutes and can provide half-hourly reporting for 10 to 15 years with virtually no maintenance .”
A wireless remote condition monitoring
106 International Mining | AUGUST 2021