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Date submitted2023-07-25
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Date accepted2024-05-02
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Date published2024-08-26
Finite element analysis of slope failure in Ouenza open-pit iron mine, NE Algeria: causes and lessons for stability control
Slope failures in mining engineering pose significant risks to slope stability control, necessitating a thorough investigation into their root causes. This paper focuses on a back analysis of a slope failure in the Zerga section of the Ouenza – Algeria open-pit iron mine. The primary objectives are to identify the causes of slope failure, propose preventive measures, and suggest techniques to enhance stability, thereby providing crucial insights for monitoring slope stability during mining operations. The study commenced with a reconstruction of the slopes in the affected zones, followed by a numerical analysis utilizing the Shear strength reduction method within the Finite element method (SSR-FE). This approach enables the examination of slope stability under both static and dynamic loads. The dynamic load assessment incorporated an evaluation of the vibrations induced by the blasting process during excavation, introducing seismic loading into the finite element analysis. The findings reveal that the primary triggering factor for the landslide was the vibration generated by the blasting process. Furthermore, the slope stability was found to be critically compromised under static loads, highlighting a failure to adhere to exploitation operation norms. The challenging geology, particularly the presence of marl layers where maximum shear strain occurs, contributed to the formation of the landslide surface. The study not only identifies the causes of slope failure but also provides valuable lessons for effective slope stability management in mining operations.
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Date submitted2021-02-24
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Date accepted2021-10-18
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Date published2021-12-16
A probabilistic approach to the dynamic cut-off grade assessment
Cut-off grade is an important conditioning parameter that determines the quantity and quality of recoverable reserves and development efficiency. Today, Russian mining companies operate with certified quality requirements. By setting permanent quality requirements, the government seeks to prevent depletion of reserves, reduced production during periods of falling prices, and decreased budget revenues, expressing the interests of all members of society. But to what extent do the permanent quality requirements protect the interests of the state? The answer to this question is ambiguous and does not lie on the surface. The State Commission for Reserves and domestic researchers are working to find a rational solution to the problem of quality requirements. One solution is dynamic quality requirements. The effectiveness of their application has been proven for individual mining companies, but it is incorrect to transfer these conclusions to the entire mineral resource base of the country. This article presents a new approach to determining the dynamic cut-off grade, which varies depending on the price of minerals. The dynamic cut-off grade is proposed to be determined based on the indicators of constant requirements to the quality of exploration work, using the maximum allowable costs in the region. The approach allows to calculate the effect of the introduction of dynamic cut-off grade in the practice of subsurface use for the state (in the form of the amount of taxes received) and for subsoil users (in the form of the amount of income). For a group of gold-bearing deposits with open-pit mining method, it was established that the development of reserves using dynamic values of the cut-off grade in periods of price changes ensures compliance with the interests of the state and subsoil users.
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Date submitted2019-04-27
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Date accepted2019-07-10
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Date published2019-10-23
Estimation of Rock Mass Strength in Open-Pit Mining
The paper presents results of an experimental study on strength characteristics of the rock mass as applied to the assessment of open-pit slope stability. Formulas have been obtained that describe a correlation between ultimate and residual strength of rock samples and residual shear strength along the weakening surface. A new method has been developed to calculate residual interface strength of the rock mass basing on data from the examination of small-scale monolith samples with opposing spherical indentors. A method has been proposed to estimate strength characteristics (structural weakening coefficients and internal friction angles) of the fractured near-slope rock mass. The method relies on test data from shattering small-scale monolith samples with spherical indentors, taking into ac- count contact conditions along the weakening surface, and can be applied in the field conditions. It is acceptable to use irregular-shaped samples in thetests.
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Date submitted2014-12-10
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Date accepted2015-02-20
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Date published2015-12-25
Opencast mine parameters sensitivity analysis at preliminary study of a mining project
- Authors:
- S. I. Fomin
- E. I. Bazarova
The article describes sensitivity analysis, aimed at variables dependence detection: to what extent open cast mine ultimate efficiency or performance will be affected when one of the key input variables is changed. The stronger the dependence effect, the higher the project implementation risk. The sensitivity analysis objective is demonstrated – principle factors identification – critical variables, capable of having a serious influence on the project implementation results, and impact verification of progressive (single) factorial changes. Sensitivity analysis in its content is a single-factor analysis. Output, as a basic performance indicator of an open cast mine, characterizes mine development intensity and is determined by mining-engineering and economic factors. It is proved that the impact degree from various parameters on the open cast mine output is characterized by elasticity ratio. The project indicators sensitivity analysis, which was carried out, allowed to establish the impact degree that various parameters have on the open cast mine output, which takes place in a high-angle ore deposit, characterized by elasticity ratio.
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Date submitted2013-07-16
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Date accepted2013-09-21
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Date published2014-03-17
Gas emission control parameters determination for sublevel caving mining systems at the «Kiselevskaya» coal mine
- Authors:
- O. I. Kazanin
- A. A. Sidorenko
- V. V. Sementsov
The results of the aero- and gas-dynamics processes numerical researches for the sublevel caving mining system with mechanized roof support in conditions of «Kiselevskaya» coal mine are given in the article. It is shown, that reliable and effective panel ventilation is provided with the technological scheme with three entries at the each sublevel. The parameters of the technological scheme are determined.
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Date submitted2010-07-01
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Date accepted2010-09-12
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Date published2011-03-21
Usage modern computer techniques for validation of actions guaranteeing opening strength of pit edge
- Authors:
- S. N. Kotlov
In this article is described an example of using program Modflow for the issues of oreation geofiltration processes numerical simulation on procedure of horizontal drainage well simulation. Also is estimated stability of pit edges in case of using system horizontal drains.
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Date submitted2009-08-23
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Date accepted2009-10-17
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Date published2010-02-01
Reseach of cutoff grade influence on economic performances of mining
- Authors:
- M. D. Morozov
Research of cutoff grade influence on economic performances of mine as well as parameters and configuration of ore deposits with the help of the advanced geoinformation system were carried out. Computer modeling of an ore chute was made; the results of calculation were presented, involvement is given.
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Date submitted2009-07-09
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Date accepted2009-09-01
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Date published2010-04-22
Method of calculation stability of the open pit edges
- Authors:
- A. V. Chebakov
During the opencast mining operations with bating and opening-up of new horizons as a result of the process duration in the near-edge rock mass, fatigue accumulates, which leads to slope deformations in the form of slide rocks, rock falls, roof breaks, and, in some cases, large-scale landslides. Given that the open pit edges are complex engineering structures, on the state of which mining operations effectiveness and safety depend, their stability control is a very urgent problem.