Compaction characteristics and energy dissipation of crushed gangue with different particle sizes under mining stress

• Published in: Environmental earth sciences Vol. 82; no. 12; p. 310
• Main Authors: He, Xiang, He, Shuxin, Yang, Ke, Wei, Zhen, Liu, Bin, Zhang, Cun
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2023; Springer Nature B.V
• Subjects: Axial strain; Axial stress; Backfill; Biogeosciences; Compaction; Crushing; Deformation; Earth and Environmental Science; Earth Sciences; Elastoplasticity; Energy dissipation; Energy exchange; Environmental Science and Engineering; Fractal geometry; Fractals; Gangue; Geochemistry; Geology; Hydrology/Water Resources; Load distribution; Loading rate; Mining; Original Article; Particle size; Strain; Stress-strain relationships; Terrestrial Pollution; Crushed gangue; Backfill mining; Fractal dimension; Energy dissipation; Compaction process
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-023-11011-0

Compaction properties of the backfill body are the key to reveal the law of roof subsidence and illustrate the mechanism of ground pressure control with gangue backfill mining. A rock mechanic testing machine and a self-designed steel cylinder were applied to conduct compaction experiments of gangue with different particle sizes, axial stresses, loading rates decided by actual mining stress in goaf. The characteristics of stress–strain, fractal dimension and energy dissipation for crushed gangue were analyzed. The stress–strain relationship of crushed gangue in the compaction process increases exponentially and can be divided into void compaction stage, structure adjustment stage and elastoplastic deformation stage. The fractal dimension will increase with the increase of axial stress, and decrease with the increase of loading rate. The energy dissipation in the process of gangue sample compaction depends on the stress–strain characteristics, that is resistance to axial deformation. Based on the experimental results, gangue particle size gradation has a more significant influence on compaction characteristics of gangue more than axial stress and loading rate. The axial strain caused by particle size ranges from 0.19 to 0.51, and the energy dissipation exceeds the range of 5 times, which are far beyond the influence of other factors.