In order to study the bearing capacity and acoustic emission characteristics of gangue aggregate, a hydraulic servo rock mechanics test system was used to conduct a confining compression test, with an acoustic emission system to collect acoustic emission information of crushed gangue aggregate. Considering the particle size distribution characteristics and stress state of broken gangue in caving zone, the stress-strain relationship, acoustic emission energy, particle size gradation and fractal dimension of gangue aggregate processes were analyzed with comparison between normal distribution and average grading under different axial stress loadings. The results show that the stress-strain curve of gangue aggregate is an exponential function relationship, but the normal distribution gangue aggregate changes significantly during the compaction process. Compared with the average gradation, the normal distribution gangue aggregate first occurs large-scale crushing phenomenon, and the frequency is higher, the distribution is more uniform, but the highest acoustic emission energy is less than the average gradation. The relationship between fractal dimension and loading stress is logarithmic function. The growth rate of fractal dimension of normal distribution gangue aggregate is higher than that of average gradation, and has a larger span interval.