Acoustic Emission and Infrared Radiation Temperature Characteristics of Coal with Varying Bedding Planes Under Uniaxial Compression

As a core structure in coal mine underground reservoirs, the coal pillar dams’ stability is susceptible to the orientation of coal bedding planes. This study examines the deformation characteristics, acoustic emission (AE) evolution, and infrared radiation temperature (IRT) response of coal specimens with varying bedding angles (0°, 30°, 60°, 90°), investigating microscopic failure mechanisms and AE-IRT correlations. The results show that compressive strength and elastic modulus follow a V-shaped trend with increasing bedding angle, initially decreasing before rising. The proportion of low-amplitude events (40–60 dB) increases, while the higher-amplitude (>60 dB) AE signals decrease with the bedding angle. The AE b-values increase with the bedding angles. Mean IRT temperatures exhibit an overall increasing trend with significant fluctuations, and fluctuation amplitudes display an N-shaped pattern. Microscopically, all specimens undergo tensile–shear composite failure, but shear failure contribution varies markedly: 30° specimens show the highest shear proportion, while 60° specimens show the lowest. There is a positive correlation between AE and IRT. The correlation coefficient (γ) is relatively low at 0°, but it is higher at 30°, 60°, and 90°. This research provides a theoretical underpinning for optimizing the design and stability evaluation of coal mine underground reservoirs.