1 EVALUATING DEVELOPMENT IN ROOFBOLTING TECHNOLOGY IN AUSTRALIAN COAL MINING Key Words

Roofbolts – cable bolts – support stiffness – rock confinement Roof bolting technology in Australian coal mines has advanced considerably during the 40 years since introduction. However, there is constant need for more efficient strata control in mining in order to improve safety, maximise productivity and decrease costs. Therefore, the changes introduced to roofbolting technology are being assessed and the directions for further future development are discussed. The main area where the majority of improvements have taken place is in the stiffness of the support. The gradual increase of the support stiffness has been achieved mainly by the introduction of chemical anchors and full encapsulation of bolts, higher grades of steel with more efficient deformations and the introduction of cable bolts and resin grouted strand bolts. Another important development occurred in the area of direct application of confinement to the rock mass by applying high support pre-tension. All the changes introduced to roof bolting technology which have resulted in better rock reinforcement are analysed and the directions for further future development are discussed