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Fractal analyses of rock damage and fracture
Published in Xie Heping, Fractals in Rock Mechanics, 2020
Rock bursts are experienced in underground mining at various localities in the world, causing death and injury to underground miners and damage to mine structures (drifts, stopes, etc.). To date, many studies have been conducted to understand the causes of rock bursts and outbursts and to predict their occurrence. The approaches made to detect rock bursts include: the microgravity method, rheological method, rebound method, drilling-yield method, microseismic method, and so on (Haramy & McDonnell, 1988). Although all of these methods have been used, none is completely reliable, and few are useful in the rapidly advancing mining environment. The US Bureau of Mines recognized microseismic technology as a potential tool for rock burst prediction as early as 1939, however, to date only a few successful predictions have been achieved (Jenkins et al., 1990). The causes may be due to two aspects: the first may be that the exact physical process of rock bursts is very complicated and too difficult to measure, and the second may be that the initial data recorded by these approaches are not completely utilized. Even so, the microseismic technique (or acoustic emission technique) is still commonly used in monitoring rock bursts.
An analysis of the stress fields induced by mining with application of parallel high performance computing
Published in G.N. Pande, S. Pietruszczak, H.F. Schweiger, Numerical Models in Geomechanics, 2020
R. Blaheta, O. Jakl, R. Kohut, A. Kolcun, J. Starý
As an example of large scale modelling in geomechanics, we now describe the assessment of the development of the stress fields during mining of the uranium ore at the deposit Rozna in the Czech Republic. The knowledge of the development of the stress fields is important for estimating of the possibility of rock bursts, estimate of the mutual influence of mining at adjacent ore veins and the assessment of suitability of various mining technologies. The described problem was solved within the project “High Performance Computing in Geosciences” where the formulated problems serve also for testing of various iterative methods for solving large scale algebraic systems.
Monitoring, assessment and mitigation of rock burst and gas outburst induced seismicity in longwall top coal caving mining
Published in Ömer Aydan, Takashi Ito, Takafumi Seiki, Katsumi Kamemura, Naoki Iwata, 2019 Rock Dynamics Summit, 2019
S. Durucan, W. Cao, W. Cai, J-Q Shi, A. Korre, G. Si, S. Jamnikar, J. Roser
Underground coal extractions lead to continuous stress and pressure redistribution around mine openings. Rock bursts are generally triggered in conditions where a slight change in stress equilibrium can lead to an instantaneous release of a large amount of stored strain energy ejecting rock and/or coal particles in the mine opening. Rock bursts have been extensively studied in hard rock mines, and less so in coal mines (Ortlepp and Stacey, 1994; Wang and Park, 2001; Haramy and McDonnell, 1988, Zhao and Jiang, 2009, Calleja and Nemcik, 2016).
Monitoring nonlinear and fast deformation caused by underground mining exploitation using multi-temporal Sentinel-1 radar interferometry and corner reflectors: application, validation and processing obstacles
Published in International Journal of Digital Earth, 2023
Kamila Pawłuszek-Filipiak, Natalia Wielgocka, Damian Tondaś, Andrzej Borkowski
In addition to significant mining deformation, the intensive extraction of raw materials and the complicated geological structure cause numerous high-energy tremors in the area of interest. Seismic events have typical magnitudes of between 1.0 and 3.5 M and are located at a depth of around 290–1000 m (Pilecka and Szermer-Zaucha 2015). The effects of tremors can be observed at and below the ground surface. Rock bursts lead to damage to the underground infrastructure of the mine, and sometimes to the deaths of miners. The tremors can also be felt by the inhabitants of nearby towns (Dubiński, Stec, and Bukowska 2019). Therefore, deformation monitoring is important in this area to mitigate mining hazards and can be facilitated by InSAR. The area of Rydułtowy mine is mostly covered by urban and rural settlements. In addition to Rydułtowy, there are other larger towns in the region, such as Radlin or Pszów.
Rock burst mechanism induced by stress anomaly in roof thickness variation zone: a case study
Published in Geomatics, Natural Hazards and Risk, 2022
Xianxi Bai, Anye Cao, Wu Cai, Yingyuan Wen, Yaoqi Liu, Songwei Wang, Xuwei Li
As a special dynamic phenomenon in coal mining, rock bursts are mainly induced by substantial local stress concentration resulting from mining activities, which severely affects underground mining safety and productivity (Cao et al. 2015; Vižintin et al. 2016; Zhao et al. 2018; Guo et al. 2019; Dou et al. 2021). Two fundamental factors account for rock bursts: the initial stress before mining and the redistribution of stress during mining (Pan and Meng 2004; Orlecka-Sikora et al. 2012; Guo et al. 2017). Stress anomaly concentration areas (faults, folds, coal pillars, etc.) are more vulnerable to rock bursts. For example, the particular roof structure near the faults, which may prevent abutment pressure from transferring to the deeper rock mass, can lead to stress concentration (Cai et al. 2021; Cao et al. 2021). Fold-induced rock bursts mainly occur when the static stress is concentrated, while the static stress is mostly horizontal (Wang et al. 2018; Guo et al. 2022). Rock bursts around pillars are mainly caused by concentrated static stress (mainly vertical stress; Cao et al. 2016).
Dynamic and static analysis of a kind of novel J energy-releasing bolts
Published in Geomatics, Natural Hazards and Risk, 2020
Xingdong Zhao, Shujing Zhang, Qiankun Zhu, Huaibin Li, Guoju Chen, Pengqiang Zhang
Rock burst is defined as damage to an excavation that occurs in a sudden or violent manner. In many deep mines, for example Crighton Mine and Kidd Creek Mine in Canada, rock burst hazards which are over the Richer magnitude 1.2 occur monthly (Jager et al. 1990; Ortlepp and Stacey 1994). Rock burst often causes dynamic damage to surrounding rock of stopes (tunnels). In a mining environment, the strain burst associated with rock fracturing and bulking may combine with rock ejection to generate very high ejection velocities up to or exceeding 10 m/s (Ortlepp 1993). The sudden release of energy also cause collapse of the entire stope (tunnel), rockbolts failure, death of the personnel, damage to the machine, moreover influence the production and development of local mining area and the stability of surface buildings (Weng et al. 2016; Zhang et al. 2016; Feng et al. 2017; Han et al. 2018). To reduce these damages, effect support is urgent.