Predictive acoustical behavior of rockburst phenomena in Gaoligongshan tunnel, Dulong river highway, China

The excavation of the Gaoligongshan tunnel encountered a complex geological condition, resulting in a disastrous rockburst. The rockburst during the excavation of the Gaoligongshan tunnel led to casualties and to the instability of supporting structures, which further damaged boring equipment. Therefore, the forecasting of rockburst events is of great importance. In this paper, areas with high or low risk of rockburst are identified using the Gaoligongshan tunnel stress-based rockburst criterion. Then, an acoustic emission (AE) method is adopted to forecast the magnitude and location of areas at high-risk of rockburst. Based on statistical analysis of AE characteristics and rockburst events, an AE-based rockburst criterion is proposed. As a result, in the Gaoligongshan tunnel, the stress-based and AE-based rockburst criteria are helpful in determining construction schemes and selecting support measures.