Microstructural evolution and strengthening mechanism of aligned steel fiber cement-based tail backfills exposed to electromagnetic induction  

作　　者：Xihao Li Shuai Cao Erol Yilmaz 

机构地区：[1]School of Civil and Resources Engineering,University of Science and Technology Beijing,Beijing 100083,China [2]State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education,University of Science and Technology Beijing,Beijing 100083,China [3]Department of Civil Engineering,Geotechnical Division,Recep Tayyip Erdogan University,Fener Rize TR53100,Turkey

出　　处：《International Journal of Minerals,Metallurgy and Materials》2024年第11期2390-2403,共14页矿物冶金与材料学报（英文版）

基　　金：financially supported by the China’s National Key Research and Development Program(No.2022YFC2905004);the China Postdoctoral Science Foundation(No.2023M742134).

摘　　要：Cemented tailings backfill(CTB)not only boosts mining safety and cuts surface environmental pollution but also recovers ores previously retained as pillars,thereby improving resource utilization.The use of alternative reinforcing products,such as steel fiber(SF),has continuously strengthened CTB into SFCTB.This approach prevents strength decreases over time and reinforces its long-term durability,especially when mining ore in adjacent underground stopes.In this study,various microstructure and strength tests were performed on SFCTB,considering steel fiber ratio and electromagnetic induction strength effects.Lab findings show that combining steel fibers and their distribution dominantly influences the improvement of the fill’s strength.Fill’s strength rises by fiber insertion and has an evident correlation with fiber insertion and magnetic induction strength.When magnetic induction strength is 3×10^(-4) T,peak uniaxial compressive stress reaches 5.73 MPa for a fiber ratio of 2.0vol%.The cracks’expansion mainly started from the specimen’s upper part,which steadily expanded downward by increasing the load until damage occurred.The doping of steel fiber and its directional distribution delayed crack development.When the doping of steel fiber was 2.0vol%,SFCTBs showed excellent ductility characteristics.The energy required for fills to reach destruction increases when steel-fiber insertion and magnetic induction strength increase.This study provides notional references for steel fibers as underground filling additives to enhance the fill’s durability in the course of mining operations.

关 键 词：electromagnetic induction steel fiber cemented tailings backfill strength microstructure 

分 类 号：TD926.4[矿业工程—选矿]