Punkkinen, A, Li, G & Taheri, A 2023, 'Dynamic impact and static testing of self-drilling dynamic bolt types installed in Normet’s urea-silicate injection resin: a new path forward to reducing worker exposure to high-stress ground conditions', in J Wesseloo (ed.), Ground Support 2023: Proceedings of the 10th International Conference on Ground Support in Mining, Australian Centre for Geomechanics, Perth, pp. 285-300, https://doi.org/10.36487/ACG_repo/2325_19
(https://papers.acg.uwa.edu.au/p/2325_19_Punkkinen/)
Abstract: In deep mining operations, large deformation of surrounding rock and rockbursts have become unavoidable concerns worldwide, exposing workers to high-stress hazards. In response to these challenges, Normet has developed high-energy dissipation self-drilling dynamic bolt (SDDB®) varieties installed in urea-silicate injection resin. This research evaluates the static and dynamic performance of Normet’s fully encapsulated SDDB. To enable a comprehensive evaluation, an innovative test method utilising continuous and split tube configurations was developed to assess the installation of fully encapsulated bolts in both intact surrounding rock and jointed rock mass. The tests included pull tests, shear tests, continuous tube drop tests and split tube drop tests. Static tests provided insights into the yield load, maximum load, failure load, and bolt elongation under tensile and shear stress, while the dynamic tests evaluated the performance of the SDDB during impact and characterised the failure patterns of the bolts. The fully encapsulated Leinster SDDB exhibited a maximum load capacity of 349.8 kN with 80 mm elongation in the pull test. In comparison, the Onaping SDDB withstood a shear load of 282.6 kN and generated a displacement of 27 mm. Furthermore, the Nevada and Nordic coupled SDDB demonstrated a total elongation of 196 mm and withstood an impact load of 271 kN in the drop test. These research findings highlight the exceptional mechanical properties of Normet’s SDDB and its efficacy as a dynamic ground support component in high-stress environments.

Keywords: high-stress, dynamic bolt, mechanical performance, static and dynamic, fully encapsulated