Precursory and damage characteristics of static and dynamic failures in granite under biaxial compression with different loading rates: Insight from sound signals

In deep rock engineering, rocks adjacent to excavation boundaries, subjected to biaxial compression, frequently encounter severe static and dynamic hazards induced by construction activities. These processes generate abundant sound signals associated with rock pre-failures, although the beneficial characteristics of these signals remain inadequately understood. Their potential drives us to comprehensively explore the precursory and damage characteristics of static (spalling) and dynamic (rockburst) failures in granite under biaxial compression with different loading rates using sound signals. Based on the characteristic analysis of sound signals in the time and frequency domains, we identified multiple precursors correlated with the rock failures and introduced a prediction method for determining the rock failure modes (spalling and rockburst). Subsequently, the strong effects of loading rate on the sound precursors were revealed. Moreover, the proposed sound-based damage constitutive model for granite under biaxial compression with different loading rates was proven to be feasible. Furthermore, the amplitude-frequency properties of sound signals produced by rock cracking under biaxial compression were uncovered. The research results of this study improve the prediction and warning of static-dynamic mechanisms driven rock failures under biaxial compression through sound monitoring technology.