MMS Rock Stress Measurement News

We have been very busy with R&D on our diamond drill rig. We now have remote controls to operate the drill rig. This keeps the drill operator safe from burst hydraulic hoses and reduces the chance of people being caught in rotating parts.

We also have been working on a R&D project for collection of data from the overcore and biaxial tests. We now have a system where the data is sent to a computer and the strain gauge values are returned in real time. Our software also enables plotting of the tests in progress. The data is then stored to the computer (and also to the logger as backup). The data is automatically stored in our stress programme format and we can have the full 3 stress field result minutes after completing the overcore and biaxial tests.

We have recently completed a large project in Brazil. Currently we are working on a large project at a mine in Tasmania, and prior to that mines in Northern Territory, South Australia, Queensland and Western Australia.

MMS has just completed testing at Newcrest's Cadia East Project in NSW. Prior to our drill and equipment going underground it had to comply with the NSW Department of Mines MDG15 regulations and also satisfy Newcrest's interpretation of these regulations. Two independent audits were undertaken on our drill and equipment. Our equipment passed these audits and is now MDG15 compliant, which means our equipment can be used at any mine in NSW.

We conducted tests at 1 site. We had a good run once our equipment was underground, drilling to depth, overcoring 3 CSIRO HI cells and installing a monitoring cell in 5 days. There will probably be another 2 sites early next year to test as well.

Early next year we have 2 mines in Western Australia to conduct overcoring tests at, one in South Australia and another one in NSW. There is also a possibility of a large project overseas.

MMS has just released a new version of stress monitoring analysis software for CSIRO HI cells. Multiple stress runs are possible with just a click of a button.

MMS has also just released a new version of stress measurement analysis software (Stress 2011) for CSIRO HI cells. It is now compatible with MS Excel 2007 and 2010. It is also backward compatible with Excel 2003. Soon we will be adding an online software manual in our download section. If you currently hold a Licence for the software and would like an upgrade please email us

Last year was very busy and challenging for MMS conducting stress measurement tests. Some sites have been technically challenging with poor core, debonding of gauges from the CSIRO cell, borehole breakout and discing of the core. Some of these sites have been deeper than +1500m and highly stressed. In order to get "good" stress measurement results at some mines we have had to conduct USBM cell overcores as well as using CSIRO HI cells. This USBM cell (2D) does not rely on gluing the gauges to the pilot hole. This information has been invaluable for confirming the results from the HI cells.

We have also been busy modifying our overcore drill rig and developing a heat exchange unit to heat the water for overcore tests (see our FAQ page on the importance of temperature control).

After finishing the Neves Corvo report early last year we have been testing at Ernest Henry Mine, Freeport Indonesia (3 mines 9 sites), Gwalia deeps, Otter-Juan mine and Oyu Tolgoi Project in Mongolia.

This year as well seems likely to be another busy year. With jobs at Oyu Tolgoi again (another 3 sites), Challenger Gold mine, Cliffs Nickel Project and a couple of sites at Ernest Henry mine.

overcore power pack

New 1000 Volt Power Pack

We completed and tested our new 1000 Volt hydraulic power pack for our overcore drill rig. This makes it quite a versatile drill rig now as we have the option of diesel or electric power packs. We have used this electric power pack at Cosmos Nickel Project, Ernest Henry mine and also Gwalia Deeps mine. This power pack is easy to set up underground with a single Flyght pump plug for the power. As the power pack does not draw many amps it can be used in combination with a Jumbo drill from the same electrical box.

stress measurement drill

Neves Corvo Mine

We were contracted by Somincor to conduct stress measurement tests for the Neves Corvo Lombador Project. Previous attempts at stress measurement tests by others were inconclusive. We air freighted our gear including our overcore drill rig to Portugal. We only supplied the drill and control panel and Neves Corvo provided the hydraulic power pack and hoses. One site was in the footwall shales and the other in the massive sulphides. We used a combination of USBM and HI cells tests to calculate a site result.