Geotechnical Instruments

Geotechnical Instruments

Technological advances have radically improved the way we use geotechnical instruments.

Operating as safely as possible is a top priority for all responsible mine operators. Unfortunately, mining, especially underground mining, is, by its very nature, a potentially hazardous activity.

There is always the risk of a rock fall or tunnel collapse trapping miners underground. In addition to the safety hazards they pose, cave-ins and collapses can also cause major damage to mine property and mining equipment. Another problem caused by mining accidents is reduced production, and therefore revenue, while repairs are made and cleanup operations are undertaken.

Being able to intensively and accurately monitor ground movement allows mine engineers to anticipate potentially dangerous situations before they occur and respond to them with appropriate management strategies and countermeasures when necessary. This helps make mining more predictable, and therefore much safer.

Geotechnical instruments, in various forms, have been used by miners for quite some time. Early instruments were mostly mechanically based and needed to be read manually using a caliper or other form of measurement gauge– a time-consuming and labour-intensive process that limited the speed and practical frequency of monitoring and could also disrupt production while instruments were being read in a working area.

Major advances in electronic technology, especially relating to the development of vastly improved sensors and manufacturing techniques, have made modern geotechnical instruments much more accurate, easy to install and simpler to read.

Some of the most common geotechnical instruments in use in modern mines are:

  • Extensometers, to measure displacement (e.g. MDT SMART MPBX)
  • Instrumented Cable Bolts, to measure displacement, strain and load (e.g.
  • MDT SMART Cable Bolt)
    Contractometers, to measure convergence and compression (e.g. MDT SMART Contractometer)
  • Ground Movement Monitors, to measure general ground movement (single-point) (e.g. MDT SMART GMM100)
  • Sloughmeters, to measure sloughing or caving (e.g. MDT Sloughmeter)
    The increasing availability and popularity of wireless mesh networks within underground mines has taken the monitoring of geotechnical instruments into a whole new era.

It is now possible to link hundreds (or thousands) of geotechnical instruments together using a wireless mesh network that consists of the instruments themselves, wireless nodes that can simultaneously connect to multiple instruments (e.g. the MDT-RTU), and one or more Ethernet gateways to feed gathered data into the mine’s existing LAN (local area network).

For best results, the geotechnical instruments that are the foundation of an underground mine’s mesh sensor network should be monitored by a comprehensive wireless monitoring and control system like the Newtrax MineHop™ system.

MineHop™ reads data from all of the geotechnical instruments (and certain other monitoring devices) installed in an underground mine, processes it, and makes it readily available to mine engineers. Information is provided in standard, easy-to-understand formats that can be read on a regular computer (desktop or laptop) already in use.

Because engineers can access up-to-date, accurate data right from their offices (or even view it offsite by using the included MineHop™ web interface), they need to spend a lot less time underground than would be the case if more manual systems were used. This reduces risk and allows them to spend more of their time analyzing data and using it to make the mine a lot safer and more productive, rather than wasting their time gathering it.