Numerical investigation of the influence of waste rock inclusions on tailings consolidation

2014 ◽  
Vol 51 (9) ◽  
pp. 1021-1032 ◽  
Author(s):  
Frédérick L.Bolduc ◽  
Michel Aubertin
Keyword(s):  
Cross Section ◽  
Hard Rock ◽  
Waste Rock ◽  
Mine Wastes ◽  
Compression Index ◽  
Tailings Impoundment ◽  
Pore Water Pressures ◽  
Zone Of Influence ◽  
Main Factors ◽  
Hard Rock Mines

The construction of waste rock inclusions (WRIs) in a tailings impoundment constitutes an alternative disposal technique that aims at improving the management of mine wastes. This technique consists in strategically placing the WRIs inside the impoundment, at the beginning and during its operation, to form compartments (or cells) in which the tailings are stored. Such inclusions can serve various purposes. In this paper, the authors investigate the effects of drainage from WRIs on tailings consolidation during filling of the impoundment, using experimental data from hard rock mines that provide the hydrogeological and geotechnical properties introduced in the numerical analyses. The model used for the simulations represents a cross section of a portion of a tailings impoundment containing a WRI. The numerical calculations results illustrate how the WRI affects the dissipation of the excess pore water pressures (PWPs) during filling of the impoundment, and help quantify the extent of the zone of influence of the inclusion. The results from the parametric analysis show that the saturated hydraulic conductivity ksat, compression index Cc, thickness, and deposition rate of the tailings are the main factors that affect the efficiency of WRIs to accelerate dissipation of excess PWPs. The discussion that follows recalls the main limitations of this investigation and addresses practical aspects related to the WRIs technique.

Consolidation of hard rock tailings under positive and negative pore-water pressures: testing procedures and experimental results

2021 ◽  
Vol 58 (1) ◽  
pp. 49-65 ◽  
Author(s):  
Karim Essayad ◽  
Michel Aubertin
Keyword(s):  
Pore Water ◽  
Hard Rock ◽  
Experimental Results ◽  
Compression Tests ◽  
Testing Procedures ◽  
Vertical Loading ◽  
Pore Water Pressures ◽  
Experimental Protocols ◽  
First Time ◽  
Hard Rock Mines

This paper presents laboratory testing procedures and key results on the consolidation of tailings from hard rock mines under positive or negative pore-water pressures (PWP). Specific experimental protocols have been developed and applied to assess the behaviour of low-density tailings (slurry) using compression tests in instrumented columns. The testing results on saturated specimens with positive PWP are used to determine the primary and secondary compression (consolidation) parameters of the tailings, based on excess PWP and displacement measurements. The compression tests with controlled negative PWP were conducted using two stress paths: vertical loading with a constant (imposed) suction and with a progressively increasing suction. The results from these tests illustrate specifically, for the first time, the combined effects of the net vertical stress and suction on tailings compressibility parameters, and on the evolution of PWP. The experimental procedures and related experimental results presented here can be quite useful for the analysis of tailings consolidation in the field, where both positive and negative PWP can occur.

Research and Application of Subsidiary Transport in Mines Based on Flexible Surge Bin Design

2010 ◽  
Vol 42 ◽  
pp. 77-81
Author(s):  
Li Rong Wan ◽  
Zai Chang Wang
Keyword(s):  
Cross Section ◽  
Transport System ◽  
Waste Rock ◽  
Large Cross Section ◽  
Main Factors

The concept of flexibly connected surge bin transport system was given in this paper. On this basis, the reliability of subsidiary transport system in mines has been researched, and the main factors that affect the system’s reliability were given. After the flexible surge bin was applied, Xin Wen Mining Bureau successfully carried out new subsidiary transport methods, for example: storing the coal and waste rock in different places and transporting them at different time with different ways, and disposing the waste rock timely at the large cross-section all-rock driving face, etc. The achievements in Xin Wen Mining Bureau prove that the flexible surge bin can remarkably improve the reliability of subsidiary transport system, so the application of the flexible surge bin really has a promising prospect.

Effect of waste rock inclusions on the seismic stability of an upstream raised tailings impoundment: a numerical investigation

2015 ◽  
Vol 52 (12) ◽  
pp. 1930-1944 ◽  
Author(s):  
Behnam Ferdosi ◽  
Michael James ◽  
Michel Aubertin
Keyword(s):  
Ground Motions ◽  
Low Frequency ◽  
Horizontal Displacement ◽  
Waste Rock ◽  
Seismic Stability ◽  
Environmental Damage ◽  
Total Width ◽  
Tailings Impoundment ◽  
Downstream Slope ◽  
Potential Failure

Over the years, seismic activity has been a relatively common cause of tailings impoundment failure. The flow of liquefied tailings from such ruptures can result in very severe consequences, including loss of life and environmental damage. A co-disposal technique consisting of placing waste rock inclusions in tailings impoundments prior to and during tailings deposition was proposed by the authors. The waste rock is placed to create continuous inclusions within the impoundment, which provide a number of environmental and geotechnical benefits, particularly with respect to seismic stability. The results of numerical simulations previously performed have shown that the UBCSAND model can predict the seismic response of tailings. The UBCSAND constitutive model was used to conduct simulations to evaluate of the use of waste rock inclusions to improve the seismic stability of a tailings impoundment. The evaluation consists of numerical analyses of an actual tailings impoundment as constructed (without inclusions), and then assuming that it was constructed with inclusions, subjected to earthquake loads of various energy contents and with different predominant frequencies. The analyses were conducted in static, seismic, and post-shaking phases. The displacement of the surface of downstream slope of the tailings dyke was recorded during the analyses. The results indicate that the presence of waste rock inclusions can significantly improve the seismic behavior of the impoundment by reducing the displacements of the surface of the downstream slope and the extent of potential failure zones. Also, the results show that in most cases, the influence of a low-frequency earthquake on the displacement of the downstream slope of the tailings dyke is more important than that of a high-frequency earthquake. The performances of the tailings impoundment with different configurations of waste rock inclusions (varying width and center-to-center spacing) were classified based on the average normalized horizontal displacement of the downstream slope (ARx) for a range input ground motions. Charts were then developed to show how ARx is influenced by the total width of inclusions, their spacing, and the input ground motions.

Numerical modeling approach for design of water-retaining dams in underground hard rock mines—a case example

2018 ◽  
Vol 11 (23) ◽  
Author(s):  
John Loui Porathur ◽  
Minnie Jose ◽  
Rana Bhattacharjee ◽  
Subashish Tewari
Keyword(s):  
Numerical Modeling ◽  
Hard Rock ◽  
Modeling Approach ◽  
Hard Rock Mines

scholarly journals Large-scale deformation in underground hard-rock mines

2015 ◽  
Vol 115 (7) ◽  
pp. 645-652 ◽  
Author(s):  
E. Karampinos ◽  
J. Hadjigeorgiou ◽  
P. Turcotte ◽  
F. Mercier-Langevin
Keyword(s):  
Large Scale ◽  
Hard Rock ◽  
Hard Rock Mines

The Case of Failure Analysis of the PCBA Wire Corrosion under High Reliability Requirements

2019 ◽  
Vol 2019 (1) ◽  
pp. 000369-000372
Author(s):  
Jie Zheng ◽  
Yabing Zou ◽  
Ying Yang ◽  
Jianghua Shen ◽  
Yingjie Zhang
Keyword(s):  
Cross Section ◽  
Ion Chromatography ◽  
Visual Inspection ◽  
High Reliability ◽  
Cleaning Process ◽  
Chromatography Analysis ◽  
Wave Soldering ◽  
Bromide Ion ◽  
Main Factors ◽  
Type Of Failure

Abstract The wire breakage of a no-cleaning process PCBA occurs at the beginning of the application. Through visual inspection, cross-section, SEM & EDS, and ion chromatography analysis, it was found that the high content of ions (bromide ion) on the surface of the solder source side caused corrosion and fracture of the conductors of wave soldering surface, this article also analyzes the source of bromide ion and conclude the main factors involved in this type of failure.

scholarly journals Large-scale destress blasting for seismicity control in hard rock mines: A case study

2020 ◽  
Vol 30 (2) ◽  
pp. 141-149 ◽  
Author(s):  
Isaac Vennes ◽  
Hani Mitri ◽  
Damodara Reddy Chinnasane ◽  
Mike Yao
Keyword(s):  
Large Scale ◽  
Hard Rock ◽  
Destress Blasting ◽  
Hard Rock Mines

Numerical Simulation of Triangle-Arranged Tubular Heat Exchanger

2013 ◽  
Vol 341-342 ◽  
pp. 546-549
Author(s):  
Hui Li ◽  
Rui Hua Hu
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Cross Section ◽  
Field Distribution ◽  
Pressure Field ◽  
Geometric Model ◽  
Temperature Field Distribution ◽  
Tubular Heat Exchanger ◽  
Computational Fluid Dynamics Cfd ◽  
Main Factors

Based on the principle and method of computational fluid dynamics (CFD), using the software, FLUENT, the inner water flow field in the cross-section geometric model of a triangle-arranged tubular heat exchanger was simulated and the flow details were studied roundly. This article analyzed the temperature field distribution, pressure field distribution and pointed out the main factors that affected the effect of the heat transfer. The results of this paper provided a good base and reference for the further research on the optimum design.

Sign in / Sign up

Export Citation Format

Share Document