The assessment of the performance of ground support systems under dynamic loading is typically subjected to qualitative and subjective interpretations. As a result, it is difficult to develop an explicit knowledge of the mechanisms of action and interaction of support elements subjected to rockbursts. This paper examines rockbursts that occurred at Creighton and Copper Cliff mines since 2000 and 2004, respectively. The majority of pertinent information was obtained through onsite field assessments, seismic system records, and numerical elastic stress modelling. Passive monitoring is used to link the evolution of the frequency and severity of rockbursts to the evolution of mining and support practice at the two mine sites. Based on the collected data, ground-support elements that enhanced the capacity of support systems to withstand dynamic loads are identified. https://papers.acg.uwa.edu.au/p/1410_09_Hadjigeorgiou/ The influence of change in mining and ground support practice on the frequency and P Morissette et al. severity of rockbursts

This paper reports on an ongoing analysis of support performance at Vale's Creighton Mine covering the period from January 2000 to September 2011. A database was constructed of 133 rockbursts and the associated damage to support systems at 191 locations. The main source of information has been obtained through the seismic systems and on-site assessments. This work validates the information collected on site in order to quantify the performance of different support systems in a seismically active mine. 2 Data collection For the purpose of this investigation, it was decided to focus on data from one mine site. Creighton Mine of Vale was selected due to its long history of mining, seismicity and rockburst, the quality of its seismic data, and the considerably large range of event magnitudes recorded. The mine has always had a dedicated ground control team. A variety of rock support systems have been tested at Creighton during the past, making this mine site even more interesting for passive monitoring of support performance. This section provides the necessary background on the local geology at Creighton, mining methods and ground support practices. Sources of information available on-site and data collected are further reviewed. https://papers.acg.uwa.edu.au/p/1201_02_morissette/ Validating a support performance database based on passive monitoring data P. Morissette et al.

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The performance of ground support systems under dynamic loading is typically assessed in a qualitative and subjective manner. As a result, it is difficult to develop an explicit knowledge on the mechanisms of action and interaction of support elements subjected to rockbursts. This paper examines rockbursts that have occurred at Creighton, Copper Cliff, and Coleman mines since 2000, 2004, and 2006, respectively. The mines are located in the Sudbury Basin, in Ontario, Canada. The majority of pertinent information was obtained through on-site field assessments, seismic system records, and numerical elastic stress modelling. Passive monitoring is used to link the evolution of the frequency and severity of rockbursts to the evolution of mining and support practice at the three mine sites. Based on the collected data, ground support elements that enhanced the capacity of support systems to withstand dynamic loads are identified. rockburst, ground support systems, passive monitoring.

In underground mines, a ground support system is required to maintain the integrity of an excavation over its service life. The design of support systems typically accounts for the anticipated static loads and is, to some extent, supported by quantitative engineering guidelines. In deep and high stress mines, dynamic loads associated with mining-induced seismicity represent an important component of the demand imposed on the support. Quantifying dynamic loads that apply on, and between, reinforcement and surface support elements is an important challenge. In this respect, the design of ground support systems for dynamic-loading conditions has relied importantly on qualitative assessments of support performance. This paper presents a ground support design strategy, supported by high-quality field data, for deep and high stress mines subjected to dynamic-loading conditions. The strategy has been developed and validated using rockburst data from three seismically active mines located in the Sudbury region, Canada, and cumulating 32 years of mining.

Rockbursting is one of the important challenges faced in deep and high stress mines. Ground support systems designed for supporting static loads are often not able to manage the imposed dynamic loads. Consequently, in anticipation of dynamic-loading conditions, stiff support systems are typically enhanced using reinforcement or surface support elements that are perceived to improve the yielding capacity. In order to develop cost-effective ground support strategies, it is important to quantify the conditions that lead to an increased likelihood of rockburst. This paper provides an objective and practical guideline for the identification of burst-prone ground conditions based on the anticipated magnitude events and the associated probability of rockburst, the proximity of large-scale geological structures, and mining-induced stress conditions. The guideline was developed using passive monitoring of ground support performance under dynamic-loading conditions at Creighton Mine, operated by Vale in Sudbury, Ontario, Canada. A comprehensive database was constructed of 123 seismic events and the resulting 184 damage locations. The reported rockbursts occurred between January 2000 and September 2013. The majority of pertinent information was obtained through onsite field assessments, seismic monitoring records, and numerical stress analyses. The proposed guideline is validated for Creighton Mine and the employed methodology is transferable to other deep underground mines.

Seismic activity is known to affect the short-and long-term behaviour of mining ground support, yet the influence of seismicity on ground support demand is not fully understood. This paper quantitatively assesses the influence of various seismic parameters on the performance and degradation of ground support elements. A large database was created using the LaRonde mine (Quebec, Canada) as a case study, which consolidates information on the history of the rock support of an entire mine sector comprising 18.5 km of drifts: type, installation date, and behaviour over time. This database was linked with the seismic event database available at the mine. Analyses identified various seismic parameters (i.e. large seismic events, number of seismic events, increase in apparent stress, b-value from the Gutenberg-Richter frequency-magnitude relationship, peak particle velocity, and energy radiated from the event) as precursory trends that may influence the performance and degradation of ground support elements. A key finding is that the number of seismic events and their magnitude are contributing factors in controlling the demand on ground support. A high number of seismic events and high local magnitude event have frequently been recorded before observing degradation on ground support elements. Another important finding is that the demand on ground support cannot be explained entirely by seismicity; it is also controlled by other site factors.