Particle-Crushing Characteristics and Acoustic-Emission Patterns of Crushing Gangue Backfilling Material under Cyclic Loading

Minerals

Yanli Huang¹  Meng Li¹  Ming Qiao²  Zhongwei Chen³  Mehmet Kizil³  Junmeng Li³ 

[1] Technology, Xuzhou 221116, China;School of Mechanical and Mining Engineering, The University of Queensland, Queensland 4072, Australia;;State Key Laboratory of Coal Resources and Safe Mining, School of Mines, China University of Mining &

关键词: crushing gangue backfilling material;    cyclic loading;    particle crushing;    acoustic emission;    solid backfilling coal mining;   

DOI  :  10.3390/min8060244

来源: DOAJ

【 摘 要 】

In solid backfilling coal mining (SBCM), the crushed gangue backfilling material (CGBM) is generally compacted circularly by a compaction machine in order to reduce its compressibility. In this cyclic compaction process, the particles are crushed, which has a significant effect on the deformation resistance of CGBM. However, the deformation resistance of CGBM is critical for controlling overburden strata movement and ground surface subsidence. This study implemented an experimental approach to investigate the particle-crushing characteristics and acoustic-emission (AE) characteristics of CGBM during constant-amplitude cyclic loading (CACL). At the same time, the relationship between particle crushing and AE signals was established. The results showed that the gangue particles were generally in the shape of irregular convex polyhedrons with more edges and angles that were prone to breakage. It also demonstrated that both the crushing ratio (Bg) and the newly produced fine granule content increased with the cyclic loading times. The content of newly generated fine particles can reflect the particle-crushing conditions to a certain extent. What is more, it was found that the CGBM samples exhibited an apparent Felicity effect during CACL, and AE signals were the most active during the first loading cycle. The crushing ratio of CGBM was highly correlated to the AE signals, which indicated that AE signals can be used to reflect the particle-crushing situation of CGBM. This study is of great significance for obtaining an in-depth understanding of the mechanical properties of CGBM, as well as providing guidance for the engineering practice of SBCM.

【 授权许可】

Unknown