Mining companies across the world have traditionally used various types of in-situ ground based stability monitoring systems to monitor the stability of both surface and underground mining excavations. However, in the early year 2000 there was a massive shift from the traditional in-situ based ground monitoring techniques towards remote-based slope stability monitoring technologies such as slope stability monitoring radars.
However, findings from recent major slope failures have shown that a comprehensive and efficient slope stability monitoring system should consist of both in-situ and remote-based monitoring techniques. This is due to the fact that in most slope failures the deformation is initiated within 25-50m behind the slope surface (deep-seated). Also, there is evidence that there is substantial time difference between the on-set of slope deformation and the eventual slope failure. In instances where the remote-based or in-situ based ground stability monitoring techniques are used in isolation, there is a risk of either missing the slope failure or detecting it too late, thereby reducing the efficacy of the risk detection strategy.
Since 2016, Hoff Geotechnik has been involved in providing consulting and advanced training on slope stability monitoring to major mining companies across the world. We have been a trusted to provide rockfall hazards mitigation, slope stabilisation and secondary support of underground excavations by blue-chip mining companies across the world. As a result, we have developed expertise on in-situ ground stability monitoring.
Deep-seated ground stability monitoring systems also provides real-time insight into the near-surface and deep-seated rock mass conditions of the slope, thereby providing early warning of potential slope instability.
The in-situ based ground monitoring systems consist of multiple components and various sensors which are strategically placed across the mine within deep boreholes to detect the on-set of near-surface and deep-seated slope instability. The system also consists of a communication and software interface. The communication system consists of a data logger and transmission components.
Hoff Geotechnik’s services cover both design and implementation of the in-situ based ground stability monitoring systems. We have a team of specialised software engineers who will integrate the in-situ based ground stability monitoring system with the existing slope stability monitoring system such as slope monitoring radar and laser monitoring. We also offer advanced training covering system management and interpretation of the data.
It should be noted that in almost all the cases where ground stability monitoring system is required it is in cases where the physical site access is highly restricted. But Hoff Geotechnik have a team of specialised technicians to drill long boreholes and carry-out installations in areas with very limited site access. Hoff Geotechnik has developed extensive technical expertise and proprietary systems to safely carry-out these activities in any physical conditions. Some of the IoT sensors integrated into the monitoring system are:
- Inclinometer
- Displacement transducers
- TDR
- Piezometers
- GeoMos Prisms
