Early-age strength property improvement and stability analysis of unclassified tailing paste backfill materials
Qian Zhou , Juan-hong Liu , Ai-xiang Wu , Hong-jiang Wang
International Journal of Minerals, Metallurgy, and Materials ›› 2020, Vol. 27 ›› Issue (9) : 1191 -1202.
Early-age strength property improvement and stability analysis of unclassified tailing paste backfill materials
High-density tailings, small cementitious materials, and additives are used for backfill materials with poor early compressive strength (ECS), which may greatly affect the mining and backfill cycle, to prepare paste backfill materials (PBMs) with a high ECS. The effects and mechanisms of different early strength agents on the property of PBM are investigated. The action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction, scanning electron microscope, and energy dispersive spectrometry. Results show that the effects of single-component additives 1, 3, and 6 are better than those of the other additives, and their optimal dosages are 3wt%, 1wt%, and 3wt%, respectively. The optimum multicomponent combinations are 1wt% of additive 1 and 1.5wt% of additive 6. The ECS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive 6. The hydration product of Ca(OH)2 is consumed, and more C-S-H gels are generated with the addition of additives to paste. Tailings particles, ettringite crystals, and gels intertwined with one another form a dense net-like structure that fills the pores. This structure can significantly improve the ECS of PBM.
paste backfill / unclassified tailings / binder powder / early-age strength / microstructure
| [1] |
|
| [2] |
|
| [3] |
|
| [4] |
|
| [5] |
|
| [6] |
|
| [7] |
|
| [8] |
|
| [9] |
|
| [10] |
|
| [11] |
|
| [12] |
|
| [13] |
|
| [14] |
|
| [15] |
|
| [16] |
J.X. Fu, W.D. Song, Y.Y. Tan, and C.C. Sorrell, Study on microstructural evolution and strength growth and fracture mechanism of cemented paste backfill, Adv. Mater. Sci. Eng., 2016(2016), art. No. 8792817. |
| [17] |
J.R. Zheng, L.J. Guo, X.X. Sun, W.C. Li, and Q. Jia, Study on the strength development of cemented backfill body from lead-zinc mine tailings with sulphide, Adv. Mater. Sci. Eng., 2018(2018), art. No. 7278014. |
| [18] |
|
| [19] |
|
| [20] |
|
| [21] |
|
| [22] |
|
| [23] |
|
| [24] |
|
| [25] |
|
| [26] |
|
| [27] |
|
| [28] |
|
| [29] |
|
| [30] |
|
| [31] |
|
| [32] |
|
| [33] |
|
| [34] |
|
| [35] |
|
| [36] |
|
| [37] |
|
| [38] |
|
| [39] |
|
| [40] |
|
| [41] |
|
| [42] |
H.Q. Jiang, J. Han, Y.H. Li, E. Yilmaz, Q. Sun, and J.P. Liu, Relationship between ultrasonic pulse velocity and uniaxial compressive strength for cemented paste backfill with alkali-activated slag, Nondestr. Test. Eval. (0019). DOI: https://doi.org/10.1080/10589759.2019.1679140 |
| [43] |
|
| [44] |
A.X. Wu, Y. Wang, and H.J. Wang, Status and prospects of the paste backfill technology, Met. Mine, 2016, No. 7, p. 1. |
| [45] |
|
| [46] |
|
/
| 〈 |
|
〉 |