Experimental study on dynamic mechanical property of cemented tailings backfill under SHPB impact loading

Abstract

Cemented tailings backfill (CTB) have increasingly been used in recent years to improve the stability of mining stopes in deep underground mines. Deep mining processes are often associated with rock bursting and high-speed dynamic loading conditions. Therefore, it is important to investigate the characteristics and dynamic mechanical behavior of CTB. This paper presents the results of dynamic tests on CTB specimens with different cement and solid contents using a split Hopkinson pressure bar (SHPB). The results showed that some CTB specimens exhibited one to two lower stress peaks after reaching dynamic peak stress before they completely failed. The greater the cement-to-tailings ratio is, the more obvious the strain reaction. This property mainly manifested as follows. First, the dynamic peak stress increased with the increase of the cement-to-tailings ratio when the impact velocity was fixed. Second, the dynamic peak stress had a quadratic relationship with the average stress rate. Third, the cement-to-tailings ratio could enhance the increase rate of dynamic peak stress with strain rate. In addition, the dynamic strength enhancement factor K increased with the increase of strain rate, and its value was larger than that of the rock samples. The failure modes of CTB specimens under low-speed impact were tensile failure and X conjugate shear failure, where were nearly the same as those under static uniaxial and triaxial compression. The CTB specimens were crushed and broken under critical strain, a failure mode similar to that of low-strength concrete. The results of the experimental research can improve the understanding of the dynamic mechanical properties of CTB and guide the strength design of deep mining backfills.

Keywords

impact loading test / cemented tailings backfill / dynamic mechanical properties / split Hopkinson pressure bar

References

[1] He MC, Xie HP, Peng SP, Jiang YD. Study on rock mechanics in deep mining engineering. Chin. J. Rock Mech. Eng., 2005, 24(16): 2803.

[2] Hassani FP, Mortazavi A, Shabani M. An investigation of mechanisms involved in backfill-rock mass behavior in narrow vein mining. J. South Afr. Inst. Min. Metall., 2008, 108(8): 463.

[3] Rankine R, Pacheco M, Sivakugan N. Underground mining with backfills. Soils Rocks, 2007, 30(2): 93.

[4] Li P, Cai MF, Guo QF, Miao SJ. Characteristics and implications of stress state in a gold mine in Ludong area, China. Int. J. Miner. Metall. Mater, 2018, 25(12): 1363.

[5] Benzaazoua M, Bussière B, Demers I, Aubertin M, Fried Blier A. Integrated mine tailings management by combining environmental desulphurization and cemented paste backfill: Application to mine Doyon, Quebec, Canada. Miner. Eng., 2008, 21(4): 330.

[6] Fall M, Pokharel M. Coupled effects of sulphate and temperature on the strength development of cemented tailings backfills: Portland cement-paste backfill. Cem. Concr. Compos., 2010, 32(10): 819.

[7] Sivakugan N, Rankine RM, Rankine KJ, Rankine KS. Geotechnical considerations in mine backfilling in Australia. J. Cleaner Prod., 2006, 14(12–13): 1168.

[8] Yang L, Qiu JP, Jiang HQ, Hu SQ, Li H, Li SB. Use of cemented super-fine uncoarse tailings backfill for control of subsidence. Minerals, 2017, 7(11): 216.

[9] Liu ZX, Dang WG, He XQ. Undersea safety mining of the large gold deposit in Xinli District of Sanshandao Gold Mine. Int. J. Miner. Metall. Mater., 2012, 19(7): 574.

[10] Ouellet S, Bussière B, Aubertin M, Benzaazoua M. Microstructural evolution of cemented paste backfill: Mercury intrusion porosimetry test results. Cem. Concr. Compos., 2007, 37(12): 1654.

[11] Yilmaz E, Belem T, Benzaazoua M. Specimen size effect on strength behavior of cemented paste backfills subjected to different placement conditions. Eng. Geol., 2015, 185, 52.

[12] Torres VFN, da Gama CD, e Silva MC, Neves PF, Xie Q. Comparative stability analyses of traditional and selective room-and-pillar mining techniques for sub-horizontal tungsten veins. Int. J. Miner. Metall. Mater., 2011, 18(1): 1.

[13] Zhang JX, Li BY, Zhou N, Zhang Q. Application of solid backfilling to reduce hard-roof caving and longwall coal face burst potential. Int. J. Rock Mech. Min. Sci., 2016, 88, 197.

[14] Deng DQ, Liu L, Yao ZL, Song KIIL, Lao DZ. A practice of ultra-fine tailings disposal as filling material in a gold mine. J. Environ. Manage., 2017, 196, 100.

[15] Ke X, Hou HB, Zhou M, Wang Y, Zhou X. Effect of particle gradation on properties of fresh and hardened cemented paste backfill. Constr. Build. Mater., 2015, 96, 378.

[16] Khoshand A, Fall M. Geotechnical characterization of peat-based landfill cover materials. J. Rock Mech. Geotech. Eng., 2016, 8(5): 596.

[17] Li M, Zhang JX, Zhou N, Huang YL. Effect of particle size on the energy evolution of crushed waste rock in coal mines. Rock Mech. Rock Eng., 2017, 50(5): 1347.

[18] Cui L, Fall M. Mechanical and thermal properties of cemented tailings materials at early ages: Influence of initial temperature, curing stress and drainage conditions. Constr. Build. Mater., 2016, 125, 553.

[19] Ercikdi B, Kesimal A, Cihangir F, Deveci H, Alp Cemented paste backfill of sulphide-rich tailings: Importance of binder type and dosage. Cem. Concr. Compos., 2009, 31(4): 268.

[20] Liu C, Han B, Sun W, Wu JX, Yao S, Hu HY. Experimental study of strength of backfilling of cemented rock debris and its application under low temperature condition. Chin. J. Rock Mech. Eng., 2015, 34(1): 139.

[21] Tesarik DR, Seymour JB, Yanske TR. Long-term stability of a backfilled room-and-pillar test section at the Buick Mine, Missouri, USA. Int. J. Rock Mech. Min. Sci., 2009, 46(7): 1182.

[22] Chen JS, Zhao B, Wang XM, Zhang QL, Wang L. Cemented backfilling performance of yellow phosphorus slag. Int. J. Miner. Metall. Mater., 2010, 17(1): 121.

[23] Marsal RJ. Mechanical Properties of Rockfill Embankment Dam Engineering, 1973, New York, John Wiley Sons Inc. 109.

[24] Fall M, Benzaazoua M, Ouellet S. Experimental characterization of the influence of tailings fineness and density on the quality of cemented paste backfill. Miner. Eng., 2005, 18(1): 41.

[25] Kesimal A, Yilmaz E, Ercikdi B, Alp Yumlu M, Ozdemir B. Laboratory testing of cemented paste backfill. Madencilik, 2002, 41(4): 11.

[26] Zhao GY, Wu H, Chen Y, Xu ZW, Li ZY, Wang EJ. Experimental study on load-bearing mechanism and compaction characteristics of mine filling materials. J. China Univ. Min. Technol., 2017, 46(6): 1251.

[27] Xu WB, Song WD, Wang DX, Yang BG, Pan WD. Energy dissipation properties of cement backfill body under triaxle compression conditions. J. China Univ. Min. Technol., 2014, 43(5): 808.

[28] Xu WB, Cao PW, Tian MM. Strength development and microstructure evolution of cemented tailings backfill containing different binder types and contents. Minerals, 2018, 8(4): 167.

[29] Xu WB, Tian XC, Cao PW. Assessment of hydration process and mechanical properties of cemented paste backfill by electrical resistivity measurement. Nondestr. Test. Eval., 2018, 33(2): 198.

[30] Xu WB, Cao PW. Fracture behaviour of cemented tailing backfill with pre-existing crack and thermal treatment under three-point bending loading: Experimental study and particle flow code simulation. Eng. Fract. Mech., 2018, 195, 129.

[31] Xu WB, Tian XC, Wan CB. Prediction of mechanical performance of cemented paste backfill by the electricity resistivity measurement. J. Test. Eval., 2018, 46(6): 2450.

[32] Xu WB, Hou YB, Song WD, Zhou YP, Yin TJ. Resistivity and thermal infrared precursors associated with cemented backfill mass. J. Cent. South Univ., 2016, 23(9): 2329.

[33] Yilmaz E, Kesimal A, Ercikdi B. Evaluation of acid producing sulphidic mine tailings as a paste backfill. Turk. J. Earth Sci. Rev., 2004, 17(S1): 11.

[34] Yilmaz E, Belem T, Benzaazoua M, Kesimal A, Ercikdi B. Evaluation of the strength properties of deslimed tailings paste backfill. Miner. Resour. Eng., 2007, 12(2): 129.

[35] Yilmaz E. Investigating the Hydro-geotechnical and Microstructural Properties of Cemented Paste Backfills Using the Versatile Cuaps Apparatus, 2010, Quebec City, Université du Québec en Abitibi-Témiscamingue (UQAT) 1.

[36] Dong L, Gao Q, Nan SQ, Du JQ. Performance and hydration mechanism of new super fine cemented whole-tailings backfilling materials. J. Cent. South Univ. Sci. Technol., 2013, 44(4): 1571.

[37] Dai J. Dynamic Behaviors and Blasting Theory of Rock, 2002, Beijing, Metallurgical Industry Press 60.

[38] Fu JX, Du CF, Song WD. Strength sensitivity and failure mechanism of full tailings cemented backfills. J. Univ. Sci. Technol. Beijing, 2014, 36(9): 1149.

[39] Liu ZX, Li XB. Research on stability of high-level backfill in blasting. Min. Metall. Eng., 2004, 24(3): 21.

[40] Li N, Zhou KP, Pan D, Zhu HL. Study on intensity response of rubble backfill to dynamic loading of medium-length hole blasting. Min. Metall. Eng., 2011, 31(4): 9.

[41] Zhang QL, Yang W, Yang S, Wang MX. Test research on stability of high-density total tailing cemented backfilling under dynamic loading. China Saf. Sci. J., 2015, 25(3): 78.

[42] Sun JH, Dou YM, Zhou J, Li B. Experimental study of the effect of strain rate on compressive property of concrete. China Concr. Cem. Prod., 2011, 5, 1.

[43] Chen RJ, Liu HW, Zeng R. SHPB dynamic experiment on silica fume concrete. Adv. Mater. Res., 2013, 631, 771.

[44] Fairhurst CE, Hudson JA. Draft ISRM suggested method for the complete stress-strain curve for intact rock in uniaxial compression. Int. J. Rock Mech. Min. Sci., 1999, 36(3): 279.

[45] Xu JY, Fan JS, Lu XC. Dynamic Mechanical Properties of Rock under Confining Pressure, 2012, Xi’an, Northwestern Polytechnical University Press 56.

[46] Wang SS, Zhang MH, Quest ST. Effect of sample size on static strength and dynamic increase factor of high-strength concrete from SHPB test. J. Test. Eval., 2011, 39(5): 898.

[47] Liu JZ, Xu JY, Lu XC, Zhang L, Wang ZD. Experimental study on dynamic mechanical properties of amphibolies under impact compressive loading. Chin. J. Rock Mech. Eng., 2009, 28(10): 2113.