Study on Micromechanical Properties of Gangue Particle Cluster under Uniaxial Compression

Abstract

Abstract Gangue filling is an important green mining technology, but it is difficult to realize the precise control of the filling and compaction effect, so that the required dense filling rate and filling material parameters cannot be guaranteed. The study of uniaxial compression meso-mechanical properties of gangue particle clusters is of great significance for maximizing the use of gangue filling technology. In this paper, in order to study the mechanical response of displacement, breakage and force chain evolution in the process of compression and compaction of gangue particles, the numerical simulation method based on discrete element is used to establish the model of gangue particle cluster. Through the overflow test, friction physical experiment and steel drum compression test, the compression simulation of gangue particle cluster is carried out, and the physical and mechanical parameters of gangue and the bonding parameters of particle cluster are obtained. The results show that with the compression process, the bonding bond presents the conversion process of bonding-breaking-contact and the crushing sequence of particle cluster tip-whole particle cluster. The formation and extension of the force chain correspond to the fragmentation, displacement and mosaic of the block, and the elongation and penetration of the high stress force chain correspond to the fragmentation of the particle cluster, which will lead to the increase of the stress concentration. The degree of influence on the stress-strain curve of gangue particle clusters from large to small is : particle shape, particle size, loading speed. It provides a theoretical basis for precise quantitative control of gangue solid compaction effect.