Study on Sound Propagation Performance of Mechanized Coal Gangue-Fine Sand Filling Body

Table 2

Physical properties of fine sand.

Specific gravity	Loose bulk density (kN·m⁻^3)	Dense bulk density (kN·m⁻^3)	Maximum porosity (%)	Minimum porosity (%)	Angle of repose (°)
2.51	14.776	16.308	39.68	33.43	30.40