DEM simulation on AE characteristics of sandstone containing holes based on moment tensors

The filling material within rock masses significantly affects the structural stability of geotechnical engineering projects, introducing uncertainty to the instability and failure processes of rock masses containing holes. To explore the acoustic emission (AE) response mechanism of sandstone containing holes with different filling materials under loading, the discrete element method (DEM) combined with moment tensor theory was employed to simulate uniaxial compression tests on such specimens. The types, amplitude distribution, and b-value characteristics of AE events during the failure process were systematically analyzed. The results indicate that: ① Under filling conditions b and c, the strength increase rates for specimens with circular, rectangular, and trapezoidal holes were 2.75%, 7.12%, and 4.35%, and 8.30%, 13.14%, and 18.03%, respectively.② The presence of filling material led to more intense AE activity, with the intensity positively correlated with the strength of the filling material. Both the cumulative number of AE events and the AE rate were higher for filled specimens compared to unfilled ones.③ Under filling condition c, the proportion of shear-type AE events was higher than that under other filling conditions, and the frequency-amplitude distribution of AE events followed a normal distribution.④ Under the same filling condition, the AE b-value was largest for the circular hole specimen, followed by the rectangular and trapezoidal hole specimens. For the same hole shape, the b-value was the smallest under filling condition c and the largest under filling condition a. These findings provide a valuable reference for analyzing the acoustic failure characteristics of rock masses containing holes under various filling conditions in engineering practice.