GRANIT™ (GRound ANchor Integrity Testing) is a unique, award winning system for testing support elements such as rock bolts, bar anchors, strand anchors and soil nails, commonly used in tunnel construction, mining projects and slope stabilisation.
At the 2010 inaugural New Civil Engineer (NCE) International Tunnelling awards in London, the Halcrow GRANIT™ system won the coveted Technical Innovation award. And at the 2011 Tunnels and Tunnelling Award GRANIT™ was highly commended in the innovative use of equipment section. The judges commented, “This is a nice bit of kit that has come a long way … its deployment by Halcrow shows its capability …. it deserves to be highly commended.”
GRANIT™’s key characteristic is its ability to quantify support element bearing loads and identify defects using non-destructive test methods. Crucial data is obtained without causing damage to the support elements or interface bonds allowing individual bolts to be repeatedly monitored throughout their life.
GRANIT™ tests by sending a series of small controlled impulses through the rock bolt using an electronic solenoid. Analysis of the captured response reveals defects such as reduced support element length, whether the support element’s design or safe working load has been exceeded and potential corrosion issues along the bolt.
The self contained test apparatus is safe, reliable, efficient and allows up to 100 support elements to be tested per shift. Once defects have been identified, a remedial program can be devised.
GRANIT™ can help provide an improved health and safety environment for workers and can be used as part of a regular condition monitoring regime.