Slip and instability mechanisms of coal‐rock parting‐coal structure (CRCS) under coupled dynamic and static loading

Abstract

Abstract The slip and instability mechanisms of coal‐rock parting‐coal structure (CRCS) under coupled dynamic and static loading were investigated using theoretical analysis and numerical simulations, and the fracture and instability processes were described by monitoring the displacement, strain, and acoustic emissions (AEs) of coal and rock parting blocks. Based on the parameters of dynamic load, three different effects on slip and instability characteristics of CRCS were presented, and the effect mechanisms of static stress, as well as amplitude and frequency of dynamic stress wave, were analyzed in detail. Finally, the direct effect on the slip and instability strength of CRCS and the frequency range of dynamic load for generating synchronous slip along two discontinuities sandwiched between coal and rock parting blocks were discussed. This work is relevant for early warning coal‐rock dynamic disasters that are triggered by the slip and fracture instability of CRCS under coupled dynamic and static loading in coal mines.

Keywords

• coal‐rock parting‐coal structure (CRCS)
• discontinuity
• dynamic stress
• instability mechanisms
• stick‐slip