(1. The Third Research Institute of Corps of Engineering，General Staff of PLA，Luoyang，Henan 471023，China；
2. School of Mechanics and Civil Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221008，China；
3. State Key Laboratory for Disaster Resistant in Civil Engineering，Tongji University，Shanghai 200092，China)
Abstract：New understandings about the mechanism of rockburst of high stress tunnel are presented on the basis of rockburst model tests. Energy accumulated within the rock mass of rockburst alone is insufficient to generate ejective rockburst，extra energy must be transmitted from the surrounding rock to rockburst mass when rockburst happens. Energy convergence from surrounding rock to burst rock is a significant premise of ejective rockburst. In the process of ejective rockburst，the transformation from static to dynamic state is caused by the surplus energy released from the surrounding rock to rockburst body. Rockburst，even intense rockburst may happen when = 0.3–0.7，because of the existence of regions with weak structures and stress concentrations in the surrounding rock. Ejective rockburst could not be realized in the existing model tests under the slow loading with the ordinary hydraulic control system of slow oil supply. New model test devices were thus developed. Test results show that the developed devices can simulate ejective rockburst phenomenon well.
2014, Vol. 33 
