Belgorod State University, Belgorod, Russia:

T. I. Rubashkina, Associate Professor at the Chair of Applied Geology and Mining, Candidate of Engineering Sciences, rubashkina@bsu.edu.ru
M. A. Korneichuk, Assistant at the Chair of Applied Geology and Mining

The subject of this research is cemented backfill mixtures made using fine and very fine natural sand with increased content of clay and flour particles. Aimed to study optimizability of grain size composition of low-grade fine and very fine natural sand, the physical and mechanical properties of sands from Bolshie Mayachki deposit in the Belgorod Region and blast-furnace granulated slag from metallurgical processing at Severstal were analyzed. Optimization of granular composition included enlargement of size modulus, reduction of specific surface of grains and decrease in the content of clay and flour particles. Initial sand was brought to standard quality level by introduction of slag sand (fractions of 0-5 mm). Then, the grain composition, particle size modulus, clay and dust-like particles content and specific surface area of each composite aggregate grain were determined using the methods described in the article. According to the test results, the increase in the proportion of slag in the composite aggregate leads to the decrease in the water demand due to enlargement of particles and lower content of clay components, which makes it possible to obtain compositions for cemented backfill with strength of 1–10 MPa at the reduced consumption of cement (by 7% on average) and with the preserved rheological characteristics.

1. GOST 8736–2014. Sand for construction works. Specifications. Moscow : Standartinform, 2019. 11 p.
2. Bazhenov Yu. M. Concrete technology : tutorial. 5th ed. Moscow : ASB, 2011. 528 p.
3. Kononova O. V., Chegaeva A. I. The different module size sand mortar investigation. Sovremennye problemy nauki i obrazovaniya. 2014. No. 3.
4. Montyanova A. N., Garkavi M. S., Kosova N. S. Features and efficiency of additives to backfill mixtures. GIAB. 2009. No. 9. pp. 287–295.
5. Vinogradov S. A., Kutuzov V. I. Technology of composing and preparation of backfill for Yakovlevsky mineа. Gornyi Zhurnal. 1991. No. 10. pp. 31–35.
6. Kalmykov V. N., Beloborodov I. S., Grigorev V. V., Saraskin A. V. Exploration of composition and preparation technology for cement-free backfills using lime-and-slag binder. GIAB. 2005. No. 7. pp. 242–245.
7. Ermolovich E. A. Cementless filling mix based on technological waste. Nauchnye vedomosti Belgorodskogo gosudarstvennogo universiteta. Ser. Estestvennye nauki. 2010. No. 9(80). pp. 156–158.
8. Gurevich B. I., Tyukavkin V. V. Binding materials made of slag of nonferrous metallurgy. Tsvetnaya metallurgiya. 2007. No. 4. pp. 10–16.
9. Ermolovich E. A., Ermolovich O. V., Ermolovich A. V., Izmestev K. A., Filimonov A. A. Composition of fill mixture. Patent RF, No. 2455493. Applied: 31.05.2011. Published: 10.07.2012. Bulletin No. 19.
10. Ananyev А. Utilization of granulated blast furnace slag. Its use as an additive to concrete. Stroitelnaya gazeta. 2009. No. 46. pp. 13.
11. Klassen V. K., Morozova I. A., Borisov I. N., Mandrikova O. S. Energy Saving and Increasing the Strength of Cement Using Steel Slag as a Raw Material Component. Middle-East Journal of Scientific Research. 2013. Vol. 18, Iss. 11. pp. 1597–1601.
12. Algermissen D., Ehrenberg A. Possibilities of EAF slag u sage in cement production. Chernye Metally. 2018. No. 9. pp. 21–27.
13. Krupnik L. A., Shaposhnik Yu. N., Shaposhnik S. N. The developoment of backfilling technology in terms of Novo-Leninogorsky mine planning. GIAB. 2015. No. 8. pp. 25–32.
14. Deng D. Q., Liu L., Yao Z. L., Song K. I.-I. L., Lao D. Z. A practice of ultra-fine tailings disposal as filling material in a gold mine. Journal of Environmental Management. 2017. Vol. 196. pp. 100–109.
15. Xing Ke, Xian Zhou, Xiaoshu Wang, Teng Wang, Haobo Hou, Min Zhou. Effect of tailings fineness on the pore structure development of cemented paste backfill. Construction and Building Materials. 2016. Vol. 126. pp. 345–350.
16. Vrancken C., Longhurst P. J., Wagland S. T. Critical review of real-time methods for solid waste characterisation: Inf orming material recovery and fuel production. Waste Management. 2017. Vol. 61. pp. 40–57.
17. Krupnik L. A., Shaposhnik Yu. N., Shaposhnik S. N., Tursunbaeva A. K. Backfilling technology in kazakhstan mines. Journal of Mining Science. 2013. Vol. 49, Iss. 1. pp. 82–89.
18. Jarvie-Eggart M. E. Responsible Mining: Case Studies in Managing Social & Environmental Risks in the Developed World. Colorado : Society for Mining, Metallurgy and Exploration, 2015. 804 р.
19. GOST 8735–88. Sand for construction work. Testing methods. Moscow : Standartinform, 2018. 29 p.