Abstract: Compared with short-hole shrinkage method， synchronous filling shrinkage method has a significant effect on ore drawing law owing to flexible isolation layer laid before a large number of ore drawing. Based on common features of two mining methods， with the help of the discrete element software， the comparative study on the evolution characteristics of the force chain in the ore drawing process between the short-hole shrinkage method and the synchronous filling shrinkage method is carried out. The results show that in the drawing process of the two mining methods， both the proportion of strong contact and force chain contact increase with the drawing times， the law of change is also different. The number of force chains varies with the increase of drawing times， but the probability distribution law of force chain length is highly consistent， which decreases exponentially. Compared with the short-hole shrinkage method， although the fluctuation range of the force chain strength in the system is small during the drawing process of synchronous filling shrinkage method， but the probability distribution of the force chain strength of the two methods first increases in exponential form and then decreases in exponential form under different drawing nodes， showing the same variation law. In the process of ore drawing， the direction distribution of force chain in the granular materials systems shows obvious change in different stages， the variation law of force chain direction and anisotropy degree characterization parameter have significant difference in each stage. The research results have certain significance for the further study on the ore flow law in the drawing process of synchronous filling shrinkage method.

Key words: short-hole shrinkage method, synchronous filling shrinkage method, loose ore, force chains, evolutionary characteristics