Rigby, A, Malovichko, D & Kaiser, PK 2024, 'Simulating the displacement and energy demand imposed by a strainburst near a tunnel', in P Andrieux & D Cumming-Potvin (eds), Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 1399-1414, https://doi.org/10.36487/ACG_repo/2465_92
(https://papers.acg.uwa.edu.au/p/2465_92_Rigby/)
Abstract: During a strainburst, there is a simultaneous energy and displacement demand placed on the support system. To better understand the evolution of this demand, high-resolution, dynamic, two-dimensional modelling was conducted of self-initiated strainbursting near an isolated circular tunnel. By analysing the results of this modelling, estimates are made of the radial damage propagation velocity (193 m/s) and the duration to form a strainburst notch (4.1 ms) that are consistent with previously reported values. It is shown that surface displacements evolve to equilibrium more slowly than damage propagation, with a duration of 14.1 ms estimated. This is consistent with source durations estimated from seismic data for small strainbursts. It is shown that for the case considered (stiff loading system, no detaching of rock), an energy pulse is generated that leads to a demand path that deviates from the hyperbolic path used in deformation-based support design (for violent strainbursting in a soft mining environment). A parametric study was conducted to quantify the effect of varying the support pressure, depth of burden, and rock mass parameters (stiffness and brittleness). These factors are shown to strongly influence the demand path generated by a strainburst.

Keywords: strainbursting, ground support, support demand, numerical modelling, seismology