Rockburst inoculation process at different structural planes and microseismic warning technology: a case study.

In the process of TBM tunnel excavation, rockbursts often occurred on the structural planes, which had the characteristics of sudden and destructive. In this paper, combined with a water conveyance tunnel engineering in northwest China, the microseismic (MS) monitoring system was used to monitor the inoculation process of rockbursts at the single structural plane and multi-structural planes. Since the narrow working space of TBM tunnel, the true reflection tomography (TRT) was used to calculate the propagation velocity of P-wave in rock mass. The variation characteristics of MS parameters at the single structural plane and the multi-structural planes were compared and analyzed. Combined with fractal theory, the spatial fractal characteristics and variation trend of MS events on the structural planes were analyzed. Finally, the support measures for rockbursts of different grades were put forward. The results of this study are helpful to understand the inoculation process of rockbursts at different structural planes and have important reference value for the early warning of rockbursts in a deep-buried tunnel. [ABSTRACT FROM AUTHOR]