Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model

Tailings dams in the seasonal frozen regions experience freeze–thaw cycles with the change in natural geography and climatic conditions, which may have a strong influence on the mechanical properties of the tailings. In this paper, the effects of freeze–thaw cycles on the mechanical properties and p...

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Main Authors: Chengju Li, Jiaxu Jin, Pengfei Wu, Beibei Xu
Format: Article
Language:English
Published: MDPI AG 2022-09-01
Series:Minerals
Subjects:
Online Access:https://www.mdpi.com/2075-163X/12/9/1125
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author Chengju Li
Jiaxu Jin
Pengfei Wu
Beibei Xu
author_facet Chengju Li
Jiaxu Jin
Pengfei Wu
Beibei Xu
author_sort Chengju Li
collection DOAJ
description Tailings dams in the seasonal frozen regions experience freeze–thaw cycles with the change in natural geography and climatic conditions, which may have a strong influence on the mechanical properties of the tailings. In this paper, the effects of freeze–thaw cycles on the mechanical properties and pore structure of tailings were investigated. Triaxial tests were carried out on tailings with different moisture contents (5%, 10%, 15%, 20%) under different confining pressures (50 kPa, 100 kPa, 200 kPa, 300 kPa) after different freeze–thaw cycles (10, 20, 30, 40, 50). The pore structures of tailings were quantitatively analyzed as well. Furthermore, grey system theory was applied to develop a shear strength prediction model for tailings in cold regions. The results showed that the optimal moisture content of tailings fell 10%–15%. The shear strength of the tailings increased under higher confining pressures, while it decreased after more freeze–thaw cycles. Irrecoverable large pore deformation between particles within the tailings was found after 40 freeze–thaw cycles. After 50 freeze–thaw cycles, the proportion of pores larger than 100 μm increased from 22.76% to 48.45%. Predictions based on the Grey Model were found to be consistent with the test results and the shear strength test law. The residual error and class ratio dispersion of the model were less than 0.2, indicating that the Grey Model has high prediction accuracy and thus can be used for the prediction of the shear strength of tailings.
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spelling doaj.art-d2c1cf8f1f2e483ea58463adece7040a2023-11-23T17:55:54ZengMDPI AGMinerals2075-163X2022-09-01129112510.3390/min12091125Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey ModelChengju Li0Jiaxu Jin1Pengfei Wu2Beibei Xu3School of Civil Engineering, Liaoning Technical University, Fuxin 123000, ChinaSchool of Civil Engineering, Liaoning Technical University, Fuxin 123000, ChinaSchool of Civil Engineering, Liaoning Technical University, Fuxin 123000, ChinaSchool of Civil Engineering, Liaoning Technical University, Fuxin 123000, ChinaTailings dams in the seasonal frozen regions experience freeze–thaw cycles with the change in natural geography and climatic conditions, which may have a strong influence on the mechanical properties of the tailings. In this paper, the effects of freeze–thaw cycles on the mechanical properties and pore structure of tailings were investigated. Triaxial tests were carried out on tailings with different moisture contents (5%, 10%, 15%, 20%) under different confining pressures (50 kPa, 100 kPa, 200 kPa, 300 kPa) after different freeze–thaw cycles (10, 20, 30, 40, 50). The pore structures of tailings were quantitatively analyzed as well. Furthermore, grey system theory was applied to develop a shear strength prediction model for tailings in cold regions. The results showed that the optimal moisture content of tailings fell 10%–15%. The shear strength of the tailings increased under higher confining pressures, while it decreased after more freeze–thaw cycles. Irrecoverable large pore deformation between particles within the tailings was found after 40 freeze–thaw cycles. After 50 freeze–thaw cycles, the proportion of pores larger than 100 μm increased from 22.76% to 48.45%. Predictions based on the Grey Model were found to be consistent with the test results and the shear strength test law. The residual error and class ratio dispersion of the model were less than 0.2, indicating that the Grey Model has high prediction accuracy and thus can be used for the prediction of the shear strength of tailings.https://www.mdpi.com/2075-163X/12/9/1125tailingsfreeze–thaw cyclestriaxial testpore structureGrey Model
spellingShingle Chengju Li
Jiaxu Jin
Pengfei Wu
Beibei Xu
Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model
Minerals
tailings
freeze–thaw cycles
triaxial test
pore structure
Grey Model
title Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model
title_full Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model
title_fullStr Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model
title_full_unstemmed Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model
title_short Effect of Freeze–Thaw Cycles on Shear Strength of Tailings and Prediction by Grey Model
title_sort effect of freeze thaw cycles on shear strength of tailings and prediction by grey model
topic tailings
freeze–thaw cycles
triaxial test
pore structure
Grey Model
url https://www.mdpi.com/2075-163X/12/9/1125
work_keys_str_mv AT chengjuli effectoffreezethawcyclesonshearstrengthoftailingsandpredictionbygreymodel
AT jiaxujin effectoffreezethawcyclesonshearstrengthoftailingsandpredictionbygreymodel
AT pengfeiwu effectoffreezethawcyclesonshearstrengthoftailingsandpredictionbygreymodel
AT beibeixu effectoffreezethawcyclesonshearstrengthoftailingsandpredictionbygreymodel