Optimising Cable Bolt Pre-tensioning Practice to Control Roadway Roof Failure Using Advanced Combined Axial and Shear Testing Facility

The primary aim of this project was to aid in the optimisation of cable bolt tensioning practice for the control of roof failure in underground mining roadways through large-scale experimental tests using the advanced combined axial and shear testing facility at Swinburne University of Technology in Melbourne. Numerical models were also developed to complement future parametric studies relating to the considered system and other potential scenarios.

The project outcomes includes:

• A survey of current cable bolt tensioning practice across mining sites located within the Australian states of NSW and Qld.
• Results from largescale experimental tests performed on an idealised cable bolt system using the advanced combined axial and shear testing facility at Swinburne University of Technology.
• Preliminary work on developing a FE model for further parametric studies. Parametric studies from the calibrated models for different cable bolt tensioning levels, cable bolt characteristics, grout characteristics and embedment characteristic would be useful for further performance characterisations.

Conclusions were reached and reported in detail, regarding:

• The mining sites survey.
• The largescale experimental tests on relative joint axial separation.
• The largescale experimental tests on relative joint shear sliding.
• The largescale experimental tests on combined relative joint shear sliding and axial separation.
• The preliminary FE modelling.