Stazick, C & Sweet, D 2026, 'Long-term monitoring of electrically connected rockbolts in different corrosive environments', in D Cumming-Potvin & J Wesseloo (eds), Ground Support 2026: Proceedings of the 11th International Conference on Ground Support in Mining, Australian Centre for Geomechanics, Perth, pp. 1-11, https://doi.org/10.36487/ACG_repo/2625_36
(https://papers.acg.uwa.edu.au/p/2625_36_Stazick/)
Abstract: Corrosion of metallic ground support can vary widely within different areas of a single mine depending on the local environment or geology. Steel mesh often runs continuously in long stretches within mine access drifts and tunnels, potentially electrically connecting areas of higher to lower corrosion. The National Institute for Occupational Safety and Health (NIOSH) investigated whether corrosion levels may be locally heightened from current flowing between ground support with different electrical potentials in their respective areas. Rockbolts placed in dissimilar laboratory environments were electrically linked to each other and monitored for current flow, thickness, and weight loss against control samples. Within these tests, 2 isolation methods – resin and phenolic plates – were evaluated to observe their effect on the current flow and corrosion rates. Rockbolts had an initially higher corrosion rate when linked to a differing environment without grouting and/or phenolic plate isolation methods before the reactions reached their stable passivated rates. The current flow for environment pairings with one or both isolation types had a lower cumulative current over time, supporting their efficacy. Investigating methods to limit corrosion rates is necessary to boost safety and understanding of the longer-term structural integrity of ground support in corrosive mine environments.

Keywords: corrosion, ground support, electrical monitoring, electrical isolation, support degradation