Li, H.; Wang, H.; Bai, L. Research on the Strength Damage and Permeability Characteristics of Cemented Paste Backfill under Chlorine Salt Erosion and Dry–Wet Cycles. Minerals2024, 14, 177.
Li, H.; Wang, H.; Bai, L. Research on the Strength Damage and Permeability Characteristics of Cemented Paste Backfill under Chlorine Salt Erosion and Dry–Wet Cycles. Minerals 2024, 14, 177.
Li, H.; Wang, H.; Bai, L. Research on the Strength Damage and Permeability Characteristics of Cemented Paste Backfill under Chlorine Salt Erosion and Dry–Wet Cycles. Minerals2024, 14, 177.
Li, H.; Wang, H.; Bai, L. Research on the Strength Damage and Permeability Characteristics of Cemented Paste Backfill under Chlorine Salt Erosion and Dry–Wet Cycles. Minerals 2024, 14, 177.
Abstract
Under the dual erosion conditions of the dry-wet cycle, which is caused by the high chloride salt concentrations in mine water and fluctuations in mine water level, cemented paste backfill (CPB) suffers serious damage and deterioration. To discuss the mechanical properties and permeability characteristics of CPB under erosion, this study designs an immersion experiment for CPB under chloride salt and dry-wet cycle conditions. Through a uniaxial compressive strength (UCS) test, the change law for the mechanical parameters of the CPB was explored, strength constitutive equation of the CPB was constructed, and the process of deterioration of the CPB was analyzed. Through the penetration test, the diffusion characteristics of packing under chloride salt and dry-wet cycle conditions were explored. The results demonstrated that the strength and elastic modulus of the CPB first increased and then decreased rapidly, with maximum decrease rates of 32.2% and 38.2%, respectively. The CPB structure presents an initial non-damage stage, initial damage stage, damage development stage, damage destruction, and residual damage stage. The chloride ion penetration depth gradually increased with an increase in the number of dry-wet cycles, with a maximum diffusion depth of 20.5 mm. The maximum apparent diffusion coefficient of chloride ion was 18.99×10-10m2/s, and the maximum concentration was 0.303 mol/L. Under the double erosion conditions due to chloride salt and dry-wet cycle, the CPB structure is seriously damaged.
Keywords
Cemented paste backfill; Chloride salt erosion; Dry-wet cycle; Permeability characteristics
Subject
Engineering, Mining and Mineral Processing
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
