关键词: 地下开采, 散体粒级, 自然安息角, 散体流动性, 物理试验

Abstract: The accumulation of ore-rock dispersion is common in mining production and is one of the main factors affecting mine production safety and ore recovery.The angle of accumulation （natural repose angle） of dispersion is one of the main characteristics of its liquidity，and also an important physical parameter.Self-made measuring device is used to conduct physical test，so as to study the variation regularity of natural repose angle of ore and rock mass dispersion with different granule grades under static and stope ore-drawing conditions.The results show that under static and stope ore-drawing conditions，the natural repose angle increases when the size fraction of particles increase，its natural repose angle is increasing gradually， and in the nonuniform ore and rock mass，with the increase of the proportion of granular ore and rock mass，its natural repose angle is also increasing gradually.The static test conditions are similar to ore drawing in pass，ore drawing in funnel and accumulation in dump，when selecting the slope angle of the ore-drawing through the well and funnel，determining the floor area and slope angle of the dump site，the corresponding parameters can be adjusted according to the particle size.According to the test results of ore-drawing conditions in stope，appropriately increasing the particle size can reduce the distance from ore outlet and the volume of the bulk，improve the operating conditions of the scraper，and improve the production efficiency.The fluidity of small granule dispersion is better than that of large granule dispersion，the granule of overburden should be larger than that of ore，which is beneficial to ore outflow.

Key words: underground mining, dispersion granule, natural repose angle, fluidity, physical test