Finite element analysis of the Superbolt under dynamic loading

Authors: Nguyen, BV; Cai, M; Challagulla, K Download Paper

DOI https://doi.org/10.36487/ACG_rep/1925_25_Nguyen

Cite As:
Nguyen, BV, Cai, M & Challagulla, K 2019, 'Finite element analysis of the Superbolt under dynamic loading', in J Hadjigeorgiou & M Hudyma (eds), Ground Support 2019: Proceedings of the Ninth International Symposium on Ground Support in Mining and Underground Construction, Australian Centre for Geomechanics, Perth, pp. 375-386, https://doi.org/10.36487/ACG_rep/1925_25_Nguyen



Abstract:
As the depth of mining and underground construction increases, rock failure leading to seismic events and rockbursting is inevitable. Rockbursts can cause fatalities and/or injuries to workers, damage mine infrastructure and/or equipment and disrupt production. To minimise rockburst risk, design measures will be required. As an important line of defence, ground control support systems are used to prevent or minimise rockburst damage to excavations and enhance workplace safety. A new, patented dynamic rockbolt (the Superbolt) that integrates a reinforcement component (SDA) and a yielding component (paddle bolt) has been developed. The paddle bolt’s shank can slide freely inside the SDA when the bolt is plastically stretched. If the epoxy resin is not properly mixed and the paddle anchor slides, the SDA acts as a secondary mechanical anchor and holds the paddle in place, allowing yielding of the paddle. This new technology allows a one-pass support system to be installed underground, which will result in significant saving in mining operations. In this paper, finite element models are developed to simulate the dynamic drop tests of the paddle Superbolt using Abaqus. The split-tube and continuous-tube drop tests are simulated, and the results from the numerical simulations are in reasonable agreement with the experimental results. A parametric study is performed based on various parameters (i.e. friction, geometry, material strength, etc.) to analyse the performance of the bolt. The results demonstrate that the quality of epoxy-resin mix, the strength and ductility of the bolt material and the corrugated pipe (SDA) influence the performance of the rockbolt. The parametric study improves understanding of the influence of various parameters on the performance of the Superbolt and aids in improving the design of this ground support technology.

Keywords: finite element analysis, rockbolt, Superbolt, paddle bolt, dynamic drop test