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  • ISSN 1005-2518 
  • Founded in 1988
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Mining Technology and Mine Management

Experimental Study on the Mechanical Properties of Layered Tailing Sand Cemented Backfill and Optimization

  • Long HAI ,
  • Rongtao BAO ,
  • Shilin TAN ,
  • Xianglong FANG
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  • School of Mechanics and Engineering,Liaoning Technical University,Fuxin 123032,Liaoning,China

Received date: 2023-03-02

  Revised date: 2023-04-08

  Online published: 2023-11-21

Abstract

In the process of tailing cemented filling goaf,the discontinuity of the filling operation causes delamination of the filling body at the interface of the two fillings.In order to study the mechanical properties of the layered tailing cemented backfill and improve the deterioration effect of stratification,three types of delaminated backfill specimens,namely,intact non-delaminated,interface natural delamination,and interface sandblasted delamination,were produced.Each delamination type contains three material ratios of 1∶4,1∶6,and 1∶8 for ash-sand ratio,and uniaxial compression tests were conducted on specimens at curing ages of 3 d,7 d,14 d and 28 d to compare and analyze the deformation and damage characteristics of specimens with different delamination characteristics,different material ratios,and different curing ages.The results show that:(1) The delamination phenomenon significantly affects the mechanical properties of the tailing sand cemented backfill,considerably reducing the uniaxial compressive strength and the elastic modulus.Comparing the intact unstratified,naturally stratified specimens,the strength reduction rate caused by stratification increase ranged from 1.41% to 19.09% and exponentially with the increase of the curing age and ash-sand ratio.It indicates that the more significant the ash-sand proportion and the longer the maintenance age,the more pronounced the weakening effect of delamination of the backfill.Comparing the naturally delaminated and sandblasted delaminated specimens,the strength gain rate due to sandblasted delamination ranges from 1.92% to 16.26%,which increases with the increase of the ash-sand ratio,decreases firstly with the rise of the curing age and then remains flat and stable,and shows a higher strength gain rate in the early curing period.(2) The modulus of elasticity of the three-layered backfill types increases exponentially with the maintenance age.The discount of the modulus of elasticity of the natural layering relative to the complete layering increases with the rise in the maintenance age and decreases with the decrease of the gray sand ratio.The modulus of elasticity of the sandblasted layering relative to the natural layering only has a relatively apparent increase at 3 d,and the rest of the age is basically at the same level.(3) Using the rate of decrease of the post-peak strength curve as the ductility evaluation criterion,the post-peak strength curves of the three-layered types of backfill show better post-peak ductility with the decrease of ash-sand ratio,and it becomes more and more evident with the increase of maintenance age.The post-peak ductility performance of different layered types of backfill is in the order of interface sandblasted layered>interface natural layered>complete non-layered.(4)The damage of the delami-nated backfill is mainly in the form of tensile damage and conjugate shear damage,and the delamination surface makes part of the vertical compressive stress transformed into horizontal tensile stress,and the cracks inside the specimen are concentrated in the soft delamination surface,which makes the compressive strength of the backfill reduced.Sandblasting treatment can improve force transmission on the delamination surface to a certain extent.In order to reduce the degradation of the material’s mechanical properties by delamination,sandblasting,and other roughening treatment can be carried out on the last filling surface at the interval of the second filling.

Cite this article

Long HAI , Rongtao BAO , Shilin TAN , Xianglong FANG . Experimental Study on the Mechanical Properties of Layered Tailing Sand Cemented Backfill and Optimization[J]. Gold Science and Technology, 2023 , 31(5) : 763 -772 . DOI: 10.11872/j.issn.1005-2518.2023.05.037

References

null Cao Shuai, Song Weidong, Xue Gaili,et al,2015.Tests of strength reduction of cemented tailings filling considering layering character[J].Rock and Soil Mechanics,36(10):2869-2876.
null Cheng Aiping, Dai Shunyi, Zhang Yushan,et al,2019.Study on size effect of damage evolution of cemented backfill[J].Chinese Journal of Rock Mechanics and Engineering,38(Supp.1):3053-3060.
null Fang Zhi, Wu Rongjie, Pei Bingzhi,et al,2021.Size effect of the shear performance on the bonding interface between new and old concrete[J].China Journal of Highway and Transport,34(11):92-103.
null Fu Jianxin, Du Cuifeng, Song Weidong,2014.Strength sensitivity and failure mechanism of full tailings cemented backfills[J].Journal of University of Science and Technology Beijing,36(9):1149-1157.
null Hou Yongqiang, Yin Shenghua, Cao Yong,et al,2022.Stress-strain relationship and damge constitutive model of cemented tailings backfill under uniaxial compression[J].Materials Reports,36(16):179-186.
null Liu Guangsheng, Yang Xiaocong, Guo Lijie,2019.Models of three-dimensional arching stress and strength requirement for the backfill in open stoping with subsequent backfill mining[J].Journal of China Coal Society,44(5):1391-1403.
null Ministry of Housing and Urban-Rural Development of the People’s Republic of China. Standard for soil test method: [S].Beijing:China Planning Press.
null Qi C C, Guo L, Wu Y,et al,2022.Stability evaluation of layered backfill considering filling interval,backfill strength and creep behavior[J].Minerals,12(2):271-271.
null Qiao D P, Cheng W H, Xie J C,et al,2019.Analysis of the influence of gradation on the strength of a cemented filling body and the cementation strength model[J].Integrated Ferroelectrics,199(1):12-21.
null Sari M, Yilmaz E, Kasap T,et al,2022.Strength and microstructure evolution in cemented mine backfill with low and high pH pyritic tailings:Effect of mineral admixtures[J].Construction and Building Materials,328:127109.1.
null Spyropoulos E, Nawaz B, Ojo A,et al,2021.Stability assessment of obliquely-bedded rock cuts using multi-prong procedures-case study[J].IOP Conference Series:Earth and Environmental Science,833(1):012042.DOI:10.1088/1755-1315/833/1/012042 .
null Su Shuai,2019.Experimental Study on Strength Characteristics of Fulltailings-Cemented Filling Body/Layered Cemented Backfill[D].Hengyang:University of South China.
null Sun Demin, Ren Jianping, Jiao Huazhe,et al,2012.Study on the properties of the unclassified tailings cemented backfill materials in a mine[J].Metal Mine,41(3):6-9,14.
null Tang Yanan, Fu Jianxin, Song Weidong,et al,2020.Mechanical properties and crack evolution of interbedded cemented tailings backfill[J].Chinese Journal of Engineering,42(10):1286-1298.
null Wang J, Song W D, Cao S,et al,2019.Mechanical properties and failure modes of stratified backfill under triaxial cyclic loading and unloading[J].International Journal of Mining Science and Technology,29(5):809-814.
null Wang Y M, Wu J Y, Pu H,et al,2022.Effect of interface geometric parameters on the mechanical properties and damage evolution of layered cemented gangue backfill:Experiments and models[J].Construction and Building Materials,349:1-17.
null Wei Xiaoming, Li Changhong, Zhang Lixin,et al,2017.The ratio parameter design and engineering optimization of high stage delayed cemented backfill[J].Journal of Mining and Safety Engineering,34(3):580-586,593.
null Yan Rongfu, Liu Jiaming, Yin Shenghua,et al,2022.Effect of polypropylene fiber and coarse aggregate on the ductility and fluidity of cemented tailings backfill[J].Journal of Central South University,29(2):515-527.
null Yang Jian, Yin Tubing, Liu Kewei,et al,2017.Study on factors affecting strength of tailings backfill body with response surface method[J].China Safety Science Journal,27(12):103-109.
null Yang L J, Hou C, Zhu W C,et al,2022.Monitoring the failure process of cemented paste backfill at different curing times by using a digital image correlation technique[J].Construction and Building Materials,346:1-11.
null Zhang Jusong,2011.Concrete Science[M].Harbin:Harbin Institute of Technology Press.
null Zhao Kang, Huang Ming, Yan Yajing,et al,2021.Mechanical properties and synergistic deformation characteristics of tailings cemented filling assembled material body with different cement-tailings ratios[J].Chinese Journal of Rock Mechanics and Engineering,40(Supp.1):2781-2789.
null Zhao Zhifang,2003.Research on Bonding Mechanism of New and Old Concrete and Its Engineering Application[M].Beijing:China Water & Power Press.
null 曹帅,宋卫东,薛改利,等,2015.考虑分层特性的尾砂胶结充填体强度折减试验研究[J].岩土力学,36(10):2869-2876.
null 程爱平,戴顺意,张玉山,等,2019.胶结充填体损伤演化尺寸效应研究[J].岩石力学与工程学报,38(增1):3053-3060.
null 方志,吴荣杰,裴炳志,等,2021.新旧混凝土结合面抗剪性能的尺寸效应[J].中国公路学报,34(11):92-103.
null 付建新,杜翠凤,宋卫东,2014.全尾砂胶结充填体的强度敏感性及破坏机制[J].北京科技大学学报,36(9):1149-1157.
null 侯永强,尹升华,曹永,等,2022.尾砂胶结充填体单轴受压应力—应变关系及其损伤本构模型[J].材料导报,36(16):179-186.
null 刘光生,杨小聪,郭利杰,2019.阶段空场嗣后充填体三维拱应力及强度需求模型[J].煤炭学报,44(5):1391-1403.
null 苏帅,2019.全尾砂胶结充填体/分层胶结充填体强度特性实验研究[D].衡阳:南华大学.
null 孙德民,任建平,焦华喆,等,2012.某矿全尾砂胶结充填物料性能研究[J].金属矿山,41(3):6-9,14.
null 唐亚男,付建新,宋卫东,等,2020.分层胶结充填体力学特性及裂纹演化规律[J].工程科学学报,42(10):1286-1298.
null 魏晓明,李长洪,张立新,等,2017.高阶段嗣后胶结充填体配比参数设计及工程优化[J].采矿与安全工程学报,34(3):580-586,593.
null 严荣富,刘家明,尹升华,等,2022.聚丙烯纤维和粗骨料对尾砂胶结充填体延性和流动性的影响[J].中南大学学报,29(2):515-527.
null 杨坚,尹土兵,刘科伟,等,2017.全尾砂胶结充填体强度影响因素响应面法研究[J].中国安全科学学报,27(12):103-109.
null 张巨松,2011.混凝土学[M].哈尔滨:哈尔滨工业大学出版社.
null 赵康,黄明,严雅静,等,2021.不同灰砂比尾砂胶结充填材料组合体力学特性及协同变形研究[J].岩石力学与工程学报,40(增1):2781-2789.
null 赵志方,2003.新老混凝土粘结机理研究与工程应用[M].北京:中国水利水电出版社.
null 中华人民共和国住房和城乡建设部. 土工试验方法标准: [S].北京:中国计划出版社.
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