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Abstract Rockbursts can be classified into the strain and impact ones according to the mechanical state upon occurring. Impact rockburst is caused by the combined static and dynamic loads in deep excavation. To develop an experimental system for simulating the impact rockburst is a very challenging issue in rock engineering. 16 simple harmonic waves together with their combinations and superimpositions were implemented in the experimental system developed and described here so that the impact wave disturbance due to the excavation blasting，the roof collapse and the fault slip etc.，could be simulated. The cubic sandstone with a circular-through-hole was initially loaded with triaxial stresses in different directions. The dynamic cyclic loading was then applied in direction，keeping the loads in and directions at constant stress level meanwhile. The data of forces and displacements during the process of impact rockburst were collected in real-time through the servo control system，so that the curve of triaxial stress-strain was obtained. The image acquisition system recorded the whole process of impact rockburst in real-time for analyzing the characteristics of spalling and ejection. The rockburst due to the static loading was carried out and was compared with the one caused by the dynamic loading. A discriminant of dynamic stress and energy for impact rockburst were established through the analysis of the dynamic stress and energy of the rock mass element in roadway.
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Received: 29 August 2013
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2014, Vol. 33 
