# Development of Rockburst Research: A Comprehensive Review
## 6 Rockburst Prevention and Control

Table 7: Worldwide survey of rockburst prevention and control. [PERSON] et al. summarized four functions required to provide a reliable support system for burst-prone conditions, shown in Figure 12, pointing out that support selection in burst-prone areas is a repeated process, which needs to be verified and modified based on field observation [191]. In terms of design of rockburst support for shallow-dipping tabular excavations in South Africa, due to the small width of stop and effect of shallow-dipping tabular geometric structure, the length of bolts is limited (usually 0.9 m) and may be less than settlement height. Steel mesh is easily damaged by the impact of blasting and cleaning operations, so it is difficult to design a stronger and permanent regional support system with large coverage, while it will also lead to the failure of regional support and single yield support to form an integrated system. [PERSON] et al. deemed that a possible solution is the use of reef boring techniques, where the reef is drilled out by boring machines from predeveloped access drives while removing miners from the hazardous stope faces [192]. [PERSON] et al. used the seismic events and rockburst events of three deep mines in the Sudbury basin of Canada to establish a comprehensive database and proposed a database-based support design strategy to determine the mine location for enhanced support, the time for dynamic support installation and selection of the appropriate surrounding rock support system [193]. Figure 11: Seven rockburst support design principles (from [30]). Figure 12: Required support functions in burst-prone ground (from [191]). A new design method for deep hard rock foundation support was proposed by [PERSON] et al. [194], shown in Figure 13, including estimation of depth failure, calculation of the static and/or dynamic demand on ground support capacity, selection of support surface and reinforcement unit, which was carried out in several deep underground mines in Western Australia. A support system for rockburst control comprises, in general, three support layers, including a layer of fully covered surface retaining devices (mesh, mesh strap and shotcrete), a layer of systematic energy absorbing rockbolts and a layer of energy absorbing cable bolts (optional) [195]. A bolt is an indispensable and important piece of equipment in a support system. Under the condition of high stress, a traditional bolt is hard to provide satisfactory rock reinforcement effect. An energy absorbing bolt with sufficient strength and good energy absorption capacity has become an internationally recognized momentous support component for underground engineering. An energy absorbing bolt dissipates energy by the stretching of the bolt body or the sliding of the inner anchor in the borehole. Compared with a traditional bolt, an energy absorbing bolt not only has a greater deformation capacity but also has higher bearing capacity, so it can absorb a large amount of energy released by rock dynamic failure [196]. Some typical energy absorbing bolts and their energy absorbing characteristic curves are shown in Figures 14 and 15. In an early stage of support design, it is significant to select the appropriate bolt. An ideal rockburst support system should be a combination of a high-strength energy absorbing bolts and high-strength fully covered surface support components [197]. [PERSON] et al. used a large-scale dynamic testbed to give the application scope of various energy absorbing bolts and classified the appropriate bolt types with different surrounding rock energy demands and deformation capacity ranges, which provided clear guidance for the initial design of the support system [198]. On the other hand, [PERSON] et al. evaluated the potential value of various rockburst support systems in deep tunnels and mines, providing guidance for the selection of support systems from an economic level [199]. Figure 13: Ground support design in deep underground mines (from [194]).