This paper attempts to present the findings involving rockbursts classification, rockburst failure criteria, and related control measures. Experimental investigations were performed using the strainburst testing machi...This paper attempts to present the findings involving rockbursts classification, rockburst failure criteria, and related control measures. Experimental investigations were performed using the strainburst testing machine and impact-induced rockburst testing machine. According to the stress paths and experimental methods, rockbursts were classified into two major groups, i.e. the strainbursts and impact-induced bursts. The mechanisms and criteria of rockburst obtained from experimental investigations were discussed. Then, the developments of constant-resistance and large-deformation bolt (CRLDB), which can adapt itself to the external loading at a constant resistance by elongating continually, were introduced. The deformation energy Of country rocks with large deformation can be absorbed by CRLDBs. Finally, the principles and the experimental results for control and prevention of rockburst using the CRLDBs were presented.展开更多
Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines.To assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst ...Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines.To assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst tests using blasting were conducted at the Kiruna Mine.In this study,a numerical simulation for one of the field tests was conducted using the LS-DYNA code to investigate the dynamic response of the ground support systems including shotcrete and rockbolts.The numerical results showed a similar particle vibration pattern and a crack pattern to those of the field measurements.The effects of the detonator position and the charge configuration on the dynamic response of ground support systems are also discussed.Numerical results indicated that the peak particle vibrations on the tested panel increase along the direction of detonation propagation.It is difficult to use different charge concentrations in one borehole to investigate the effect of different dynamic loads on the dynamic response of support systems.Numerical results also indicated that 2D numerical modeling for simulated rockburst experiments could overestimate the dynamic response of ground support systems.展开更多
文摘This paper attempts to present the findings involving rockbursts classification, rockburst failure criteria, and related control measures. Experimental investigations were performed using the strainburst testing machine and impact-induced rockburst testing machine. According to the stress paths and experimental methods, rockbursts were classified into two major groups, i.e. the strainbursts and impact-induced bursts. The mechanisms and criteria of rockburst obtained from experimental investigations were discussed. Then, the developments of constant-resistance and large-deformation bolt (CRLDB), which can adapt itself to the external loading at a constant resistance by elongating continually, were introduced. The deformation energy Of country rocks with large deformation can be absorbed by CRLDBs. Finally, the principles and the experimental results for control and prevention of rockburst using the CRLDBs were presented.
基金supported by the Centre of Advanced Mining&Metallurgy(CAMM2)at Lulea University of Technologythe support from the project of SLIM funded by the European Union’s Horizon 2020 research and innovation program under grant agreement N°730294.
文摘Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines.To assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst tests using blasting were conducted at the Kiruna Mine.In this study,a numerical simulation for one of the field tests was conducted using the LS-DYNA code to investigate the dynamic response of the ground support systems including shotcrete and rockbolts.The numerical results showed a similar particle vibration pattern and a crack pattern to those of the field measurements.The effects of the detonator position and the charge configuration on the dynamic response of ground support systems are also discussed.Numerical results indicated that the peak particle vibrations on the tested panel increase along the direction of detonation propagation.It is difficult to use different charge concentrations in one borehole to investigate the effect of different dynamic loads on the dynamic response of support systems.Numerical results also indicated that 2D numerical modeling for simulated rockburst experiments could overestimate the dynamic response of ground support systems.