Avinash Chandan; Abhishek Sharma
Abstract
Due to disposal concerns, an enormous quantity of personal protective equipment (PPE) waste from the COVID-19 pandemic constituted a severe health and environmental risk. During the pandemic, the usage of protective suits increased dramatically raising concerns about how to dispose of them to safeguard ...
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Due to disposal concerns, an enormous quantity of personal protective equipment (PPE) waste from the COVID-19 pandemic constituted a severe health and environmental risk. During the pandemic, the usage of protective suits increased dramatically raising concerns about how to dispose of them to safeguard the environment. This research work uses shredded face masks (SFM) to stabilise clayey soil for sub-grade usage. Shredded face masks are added to clayey soil to investigate consistency limits, compaction characteristics, unconfined compressive strength (UCS), and California bearing ratio (CBR). Laboratory experiments demonstrate that clayey soil geo-technical characteristics such differential free swell, consistency limits, UCS, and CBR values have improved. Based on the CBR results, the IITPAVE software is used to design flexible pavement thickness, which was reduced for various commercial vehicles per day for all combinations. Cost analysis is also done to determine the total cost for a 1000-meter stretch. The results show that addition of SFM to clayey soils strengthen the geo-technical properties of clayey soil as the UCS values increase for all curing periods of 3, 7, and 28 days with a maximum improvement of 64% for 28 days curing for 1% SFM content. Also, the CBR value is found to be increased from 1.96% to 6.72%.
B. Tokhmechi; M. Rabiei; H. Azizi; V. Rasouli
Abstract
A complete and accurate analysis of the complex spatial structure of heterogeneous hydrocarbon reservoirs requires detailed geological models, i.e. fine resolution models. Due to the high computational cost of simulating such models, single resolution up-scaling techniques are commonly used to reduce ...
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A complete and accurate analysis of the complex spatial structure of heterogeneous hydrocarbon reservoirs requires detailed geological models, i.e. fine resolution models. Due to the high computational cost of simulating such models, single resolution up-scaling techniques are commonly used to reduce the volume of the simulated models at the expense of losing the precision. Several multi-scale techniques have also been developed for simulating heterogeneous reservoirs including those in which a limited number of blocks down-scale, i.e. splitting coarse blocks into fine cells around the well-zones in the case of simulation of hydraulic fracturing. In these cases, locally computed basis functions are employed to construct a global solver at a coarse-scale such as wavelet- and kernel-based up-scaling techniques. In this paper, a novel/robust 2D block-ordering system is presented, which enables solving multi-resolution up-scaling fluid flow simulations. The results will be described for a simple model, and fluid flow equations will be developed in order to show the structure of transmissibility matrix. It is confirmed that with a developed block-ordering system not only the accuracy of history match increases but also the CPU time decreases.
Environment
Aditi Nag; Smriti Mishra
Abstract
This review paper delves into the burgeoning cultural phenomenon of dark tourism, specifically exploring its connection with Mining Heritage Towns (MHTs). The paper navigates the intricate interplay between tourism competitiveness and ethical considerations in these sites laden with historical trauma ...
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This review paper delves into the burgeoning cultural phenomenon of dark tourism, specifically exploring its connection with Mining Heritage Towns (MHTs). The paper navigates the intricate interplay between tourism competitiveness and ethical considerations in these sites laden with historical trauma through a meticulous analysis of existing literature, case studies, and ethical frameworks. Dark tourism, characterised by exploring locations associated with tragedy, has emerged as a global trend, prompting a critical examination of its economic, cultural, and ethical dimensions within mining heritage contexts. Drawing on a wide array of sources, this comprehensive review elucidates the challenges confronting managers of heritage sites, shedding light on the complex ethical dilemmas they face. The paper comprehensively analyses the complex relationship between tourism competitiveness and ethical practices. It critically evaluates the impact of dark tourism on MHTs' economic landscape, explores its cultural implications, and delves into the ethical complexities of such visits, enriching academic discourse and offering valuable guidance for practitioners and policy-makers. The study enhances understanding of dark tourism's role in MHTs and advocates for sustainable tourism development, emphasising ethical considerations in shaping the future of these unique and historically significant sites.
O.E. Ifelola
Abstract
Metals are ubiquitous within the earth crust. However, the exceptional high-level concentration of heavy metals in the soil due to natural or anthropogenic activities and the chemical forms in which they exist determine the level of risk they portend to the environment. This work was aimed at determining ...
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Metals are ubiquitous within the earth crust. However, the exceptional high-level concentration of heavy metals in the soil due to natural or anthropogenic activities and the chemical forms in which they exist determine the level of risk they portend to the environment. This work was aimed at determining the background level of the presence of seven priority toxic metals (Cr, Ni, Pb, As, Cd, Cu, Zn) in the chemical phases of the overburden topsoil of a bituminous deposit prior to mining activities through the speciation analysis. The grab samples of overburden topsoil were initially obtained and homogenized to composites based on locations for the subsequent sequential extraction procedure (SEP). The specific physico-chemical properties of the sampled soils were simultaneously determined to complement the SEP inferential analysis. The results obtained showed that most metals were spatially bounded to the Fe-Mn oxides (reducible phase) followed by the organic (oxidizable) and the carbonates phases, respectively. Fractionally, the dominant soil texture in the studied area was sand (55.45%); however, the colloidal organic matter and Fe-Mn oxide phases played the dominant roles in the sorption activities of the selected metals. The soil chemical phase with the least metal pool was the exchangeable (water/salt) soluble fraction. The overall assessment revealed that the geogenic heavy metals in the topsoil posed no threats since a marginal fraction of the metals existed in the bio-available form in non-toxic concentrations in the order of Pb > Zn > Cu, while the potential mobility of metals showed that Zn was preferentially higher than Pb and Cu, respectively.
S. Hryhorovych Nehrii; T. Oleksandrivna Nehrii; H. Viktorivna Piskurska; E. Viktorovych Fesenko; Y. Yevhenovych Pavlov; A. Mykolaiovych Surzhenko
Abstract
In this work, we focus on the technology of stabilizing roof rocks by constructing separate rock supports reinforced with metal grids. Their parameters are specified using the results of physical structural modeling. The reinforced and non-reinforced rock supports with different fractional compositions ...
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In this work, we focus on the technology of stabilizing roof rocks by constructing separate rock supports reinforced with metal grids. Their parameters are specified using the results of physical structural modeling. The reinforced and non-reinforced rock supports with different fractional compositions are arranged and tested. Their initial shapes are similar to rectangular parallelepipeds with the base width-to-length ratios of 1:1, 1:1.5, and 1:2. Their shrinkage is determined by loading the supports regarding the rock particle size and the reinforcement density. Increasing the reinforcement density leads to reducing the linear dimensions without losing load-bearing capacity. It is proved that using the grids conduces the self-wedging of the rock particles. They are most effective at the initial stage of the formation of the load-bearing core. The exponential power dependence of the relative support shrinkage on the grid partitions number is obtained. The bearing core sizes in different supports are determined. For the non-reinforced supports, the core width is about 60% of the initial support width, and for the reinforced ones, it is about 90%. The exponential dependence of the core width-to-height ratio on the number of grid partitions is established. The expression for determining the reinforced support width is obtained. The support stability depends on the smallest initial base size. The size of the rock material has a little effect on the shrinkage. Reinforcement by three metal grids leads to reducing the pliability by 21% and 24% for the supports with the side ratios of 1:1 and 2:1, respectively.
Hafeezur Rehman; Ahmad Shah; Mohd Hazizan bin Mohd Hashim; Naseer Muhammad Khan; Wahid Ali; Kausar Sultan Shah; Muhammad Junaid; Rafi Ullah; Muhammad Bilal Adeel
Abstract
The major factors affecting tunnel stability include the ground conditions, in-situ stresses, and project-related features. In this research work, critical strain, stress reduction factor (SRF), and capacity diagrams are used for tunnel stability analysis. For this purpose, eighteen tunnel sections are ...
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The major factors affecting tunnel stability include the ground conditions, in-situ stresses, and project-related features. In this research work, critical strain, stress reduction factor (SRF), and capacity diagrams are used for tunnel stability analysis. For this purpose, eighteen tunnel sections are modelled using the FLAC2D software. The rock mass properties for the modelling are obtained using the RocLab software. The results obtained show that tunnel deformations in most cases are within the safety limit. Meanwhile, it is observed that the rock mass quality, tunnel size, and in-situ stresses contribute to the deformation. The resulting deformations also affect SRF. SRF depends on the in-situ stresses, rock mass quality, and excavation sequence. The capacity diagrams show that the liner experience stress-induced failures due to stress concentration at the tunnel corners. This study concludes that tunnel stability analysis must include an integrated approach that considers the rock quality, in-situ stress, excavation dimensions, and deformations.
Exploitation
M. Mohseni; M. Ataei; R. Khaloo Kakaie
Abstract
The contamination of ores with wastes or materials of lower than the cut-off grade is referred to as dilution. Dilution is an undesirable phenomenon that, on one hand, reduces the product grade and, consequently, reduces the sales prices and, on the other hand, adds an extra cost to waste production. ...
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The contamination of ores with wastes or materials of lower than the cut-off grade is referred to as dilution. Dilution is an undesirable phenomenon that, on one hand, reduces the product grade and, consequently, reduces the sales prices and, on the other hand, adds an extra cost to waste production. Therefore, studying and evaluating the dilution risk is important in mining, and especially in underground mining. In this work, using a powerful decision-making method, i.e. Multi-Attributive Approximation Area Comparison (MABAC), the dilution risk and ranking it in underground mines are assessed. For this purpose, the most important parameters affecting the dilution in 10 mines of the Venarch manganese mines are first identified and then weighed using the Fuzzy Delphi Analytical Hierarchy Analysis (FDAHP) method. Then using the MABAC method, the dilution risk score for each mine is estimated, and subsequently, various mines are ranked as the dilution risk. Then with the implementation of the Cavity Monitoring System (CMS) and measurement of the actual dilution values, the mines are ranked in dilution. The correct matching of the results of these two rankings indicates that the MABAC method is highly effective in the ranking of the risk. At the end, the risk ranking of the mines is done using the TOPSIS method, and the lack of full compliance with the results of this method with the actual values indicates that the MABAC method is preferable to the TOPSIS method.
Rock Mechanics
Kapoor Chand; Radhakanta Koner
Abstract
In open-pit mine, safety of internal dumps is a significant pointer on the economic perspective of the overall project. It has been found in several studies that unplanned and random deposition of the overburdened material is the main reason for mishaps and failure. The study utilized unmanned aerial ...
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In open-pit mine, safety of internal dumps is a significant pointer on the economic perspective of the overall project. It has been found in several studies that unplanned and random deposition of the overburdened material is the main reason for mishaps and failure. The study utilized unmanned aerial vehicles (UAVs) to map the mine dumps, and the precise 3D geometry of the same was reconstructed to evaluate the safety using numerical methods. A framework is proposed to assess and identify the potential zone of instability in the mine dumps. The study was conducted at the open-pit mine at the Raniganj coalfield of Paschim Bardhaman in West Bengal, India. The study assessed the internal dump safety using a 3D limit equilibrium method and numerical methods. Finally, optimum parameters are suggested for the mine dumps geometry under the prevailing geo-mining conditions of the mine site. The framework proposed here for assessing critical zones in mine dumps is cost-effective, easy to use, quick, and efficient.
Rock Mechanics
Naeem Abbas; Li Kegang
Abstract
The study examined the influence of cohesion, friction angle, and tunnel diameter on stability within engineering and geotechnical frameworks, while considering the consequences of nearby excavations on the overall stability assessment. The results show that a higher angle of internal friction leads ...
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The study examined the influence of cohesion, friction angle, and tunnel diameter on stability within engineering and geotechnical frameworks, while considering the consequences of nearby excavations on the overall stability assessment. The results show that a higher angle of internal friction leads to a decrease in soil stability number and weighting coefficient. Tunnel diameter significantly affects face support pressure, with larger diameters requiring stronger support due to increased stress. Higher friction angles help stabilize tunnel faces and mitigate diameter-related pressure effects. Stress redistribution around the tunnel is significant within 2 meters from the center, transitioning to elastic behavior elsewhere. A safety factor of 1.3 ensures tensile failure prevention in single and twin tunnels. Balanced stress distribution between tunnels with a slight difference is observed under isotropic in-situ stress. Numerical modeling enhances stress estimations and reveals changes during tunnel excavation, weakening the rock mass. Ground reaction curve analysis with support measures shows reduced tunnel convergence after implementation, suggesting support strategies like extended bolts using updated rock mass rating. The study improves tunnel design and stability assessment by comprehensively understanding stress redistribution and support strategies.
A. Ramezanzadeh; M. Hood
Abstract
The first step in mining activities is rock excavation in both mine development and production. Constant pressure for cost reduction and creating an improved/safe work environment for personnel has naturally resulted in increased use of mechanical excavation systems in many mining operations. Also, mechanical ...
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The first step in mining activities is rock excavation in both mine development and production. Constant pressure for cost reduction and creating an improved/safe work environment for personnel has naturally resulted in increased use of mechanical excavation systems in many mining operations. Also, mechanical excavation and mining is more compatible with automation, meaning possibility of reduction in number of people in the active underground mines. This factor plays a major role in selection of mining systems especially considering the dire shortage of skilled labour in the industry. While these systems are an integral part of mining activities in underground soft rock mining (coal, salt, potash, trona etc.), there is a need for developing new approaches and machinery for use in the underground hard rock mining. This paper will offer a review of current and emerging technologies for mechanical hard rock excavation, including disc cutting technology, drag picks, mini-disc, and activated/oscillating disc cutter. A review of general guidelines for assessment of the potentials of new research and development on this topic and evaluation of emerging technologies for a specific mining application will also be offered.
R. Ghavami-Riabi; H.F.J. Theart
Abstract
The massive sulphide deposit at Kantienpan Cu-Zn mine is hosted by volcano sedimentary succession known as the
Areachap Group, in the eastern part of Namaqua Metamorphic Province, South Africa. The deposits were affected by a
complex deformation and metamorphic history and represent ...
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The massive sulphide deposit at Kantienpan Cu-Zn mine is hosted by volcano sedimentary succession known as the
Areachap Group, in the eastern part of Namaqua Metamorphic Province, South Africa. The deposits were affected by a
complex deformation and metamorphic history and represent examples of upper amphibolite to granulite grade
metamorphosed volcanic-hosted massive sulphide (VHMS) deposits. The principal purpose of this research is to
characterise the primary geochemical halo’s related to VHMS deposits in this mine. Lithogeochemical characterization
of the primary haloes is based on borehole samples of the footwall, ore zone and hanging wall successions.
Geochemically, the ore zone and alteration zones at Kantienpan VHMS ore deposit display a high peraluminous ratio
confirming the peraluminous nature of these zones as indicated mineralogically and lithologically. The intervals
identified in sampled borehole core with low CaO and Na2O and with high MgO and K2O contents represent the
alteration zone in the original footwall rocks of the deposit.
R. Gholami; A. Moradzadeh
Abstract
Reservoir permeability is a critical parameter for characterization of the hydrocarbon reservoirs. In fact, determination of permeability is a crucial task in reserve estimation, production and development. Traditional methods for permeability prediction are well log and core data analysis which are ...
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Reservoir permeability is a critical parameter for characterization of the hydrocarbon reservoirs. In fact, determination of permeability is a crucial task in reserve estimation, production and development. Traditional methods for permeability prediction are well log and core data analysis which are very expensive and time-consuming. Well log data is an alternative approach for prediction of permeability because they are usually available for all of the wells. Hence, attempts have been made to utilize well log data to predict permeability. However, because of complicate and non-linear relationship of well log and core permeability data, usual statistical and artificial methods are not completely able to provide meaningful results. In this regard, recent works on artificial intelligence have led to the introduction of a robust method generally called support vector machine (SVM). The term “SVM” is divided into two subcategories: support vector classifier (SVC) and support vector regression (SVR). The aim of this paper is to use SVR for predicting the permeability of three gas wells in South Pars filed, Iran. The results show that the overall correlation coefficient (R) between predicted and measured permeability of SVR is 0.97 compared to 0.71 of a developed general regression neural network. In addition, the strength and efficiency of SVR was proved by less time-consuming and better root mean square error in training and testing dataset.
Environment
Debasmita Basu; Smriti Mishra
Abstract
This study presents a comprehensive analysis of community perceptions regarding the impacts of reclamation strategies for abandoned coal mines in India, with a specific focus on the Manikpur Coal Mine. Through a structured survey administered to residents in the vicinity of the mine, the research investigates ...
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This study presents a comprehensive analysis of community perceptions regarding the impacts of reclamation strategies for abandoned coal mines in India, with a specific focus on the Manikpur Coal Mine. Through a structured survey administered to residents in the vicinity of the mine, the research investigates the economic, socio-cultural, and environmental impacts of reclamation efforts. Utilizing Structural Equation Modeling (SEM), the study identifies key factors influencing community perceptions, including the perceived benefits of reclamation, levels of community involvement, and overall satisfaction with mining operations. The findings reveal significant relationships among these factors, such as the positive influence of reclamation availability/requirement (path coefficient = 0.633) on satisfaction and the negative impact of involvement on satisfaction (-0.805). Indirect effects highlight the interplay between constructs, with experience positively influencing involvement (0.673) and satisfaction (0.162) while negatively affecting reclamation availability/requirement (-0.194). Variations in latent variable scores for satisfaction (-1.63 to 3.031) and reclamation availability/requirement (-1.42 to 1.903) underscore the diverse respondent experiences. These insights emphasize the importance of effective community engagement and tailored reclamation strategies. Policy recommendations are provided to enhance the sustainability and effectiveness of reclamation efforts, emphasizing the need for holistic approaches that integrate economic viability, socio-cultural acceptance, and environmental sustainability. The study contributes to the field of mine reclamation by offering valuable insights into resident perceptions and practical guidelines for improving reclamation practices in mining-affected areas.
Mostafa Javid; Behzad Tokhmechi
Abstract
There are two methods for identifying formation interface in oil wells: core analysis, which is a precise approach but costly and time consuming, and well logs analysis, which petrophysists perform, which is subjective and not completely reliable. In this paper, a novel coupled method was proposed to ...
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There are two methods for identifying formation interface in oil wells: core analysis, which is a precise approach but costly and time consuming, and well logs analysis, which petrophysists perform, which is subjective and not completely reliable. In this paper, a novel coupled method was proposed to detect the formation interfaces using GR logs. Second approximation level (a2) of GR log gained from optimum mother wavelet decomposition was used for formation interface detection. Short time Fourier transform (STFT) of a2 was gained since the window band was fixed in the entire of well depths. Inverse STFT of various windows of transformed data was gained, which creates various signals in depth domain. To this end, a novel formulation was developed to obtain modified signal for formation interface detection. The mean of various resulted signals creates a smooth signal the logarithm well of which highlights formation interfaces. Synthetic data were used to test the applicability of proposed algorithm. Accordingly, GR logs corresponding to five different wells located in an oilfield in south of Iran also were used to investigate the accuracy and applicability of the proposed method. Lastly, the validation process took place by comparing the results of core data analysis and the proposed method. Good agreements were obtained between these approaches, demonstrating the applicability of the proposed methodology.
M. Hemmatian; B. Tokhmchi; V. Rasouli; R. Gholami
Abstract
A good knowledge of the parameters causing casing damage is critically important due to vital role of casing during the life of a well. Cement sheath, which fills in the gap between the casing and wellbore wall, has a profound effect on the resistance of the casing against applied loads. Most of the ...
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A good knowledge of the parameters causing casing damage is critically important due to vital role of casing during the life of a well. Cement sheath, which fills in the gap between the casing and wellbore wall, has a profound effect on the resistance of the casing against applied loads. Most of the empirical equations proposed to estimate the collapse resistance of casing ignore the effects of the cement sheath on collapse resistance and rather assume uniform loading on the casing. This paper aims to use numerical modeling to show how a bad cementing job may lead to casing damage. Two separate cases were simulated where the differences between good and bad cementation on casing resistance were studied. In both cases, the same values of stresses were applied at the outer boundary of the models. The results revealed that a good cementing job can provide a perfect sheath against the tangential stress induced by far-field stresses and reduce the chance of casing to be damaged.
Asghar Azizi; Ali Dehghani; Seyyed Zioddin Shafaei
Abstract
AbstractThe purpose of this study was to investigate the controllable operating parameters influence, including pH, solid content, collector, co-collector, and depressant dose, and conditioning time, on apatite flotation kinetics. Four first order flotation kinetic models are tested on batch flotation ...
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AbstractThe purpose of this study was to investigate the controllable operating parameters influence, including pH, solid content, collector, co-collector, and depressant dose, and conditioning time, on apatite flotation kinetics. Four first order flotation kinetic models are tested on batch flotation time-recovery profiles. The results of batch flotation tests and the fitting of first-order kinetic models to assess the influence of operating parameters on the flotation kinetics indicated that model with fast and slow - floating components and classical model gave the best and the worst fit for experimental data, respectively. Also, rectangular distribution of floatabilities and gamma distribution of floatabilities fitted the experimental data well. In this study, the model with rectangular distribution of floatabilities associated with fractional factorial experimental design was employed to evaluate the effect of six main parameters on kinetic parameters (R_∞, K). The result indicated that linear effects of depressant dose, conditioning time, and the interaction effects of solid concentration and pH statistically were important on ultimate recovery but the significant parameters for flotation rate constant were linear effects of solids content, depressant dosage and the interaction effect between pH and conditioning time. Regression equations obtained to relate between flotation operation and kinetic parameters.
Hamid Khoshdast
Abstract
A new parametric model was developed for predicting cut point of hydraulic classifiers. The model directly uses operating parameters including pulp flowrate, feed particle size characteristics, pulp solids content, solid density and particles retention time in the classification chamber and also covers ...
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A new parametric model was developed for predicting cut point of hydraulic classifiers. The model directly uses operating parameters including pulp flowrate, feed particle size characteristics, pulp solids content, solid density and particles retention time in the classification chamber and also covers uncontrollable errors using calibration constants. The model applicability was first verified using a bench scale classifier and then, validated at industrial scale for a coal classifier. Results showed that the new model can predict the cut point more precisely compared to the conventional Masliyah model, i.e. the accuracy values of 80% and 37% for the new and Masliyah models, respectively. Sensitivity study showed that the model was extremely sensitive to the particle size distribution of feed while being least sensitive to the particles retention time.
M. Hosseini Nasab
Abstract
In this research work, the parameters affecting the settling velocity within the thickeners were studied by introducing an equivalent shape factor. Several thickener feed samples of different densities including copper, lead and zinc, and coal were prepared. The settling tests were performed on the samples, ...
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In this research work, the parameters affecting the settling velocity within the thickeners were studied by introducing an equivalent shape factor. Several thickener feed samples of different densities including copper, lead and zinc, and coal were prepared. The settling tests were performed on the samples, and the corresponding settling curves were plotted. Using the linear regression analysis, the Chein's equation was fitted to the experimental data in order to obtain the equivalent shape factors for the different minerals. Moreover, the relations between the equivalent shape factors and the settling parameters were investigated. The R-squared values for the fits proved the capability of the Chein’s equation to fit well on the experimental data (0.96
M. Mohebbi; A.R. Yarahmadi Bafghi; M. Fatehi Marji; J. Gholamnejad
Abstract
Presence of joints and fractures in rocks strongly influences the behavior of the rock mass by dividing the media into smaller units. These structures intensify the potential instability besides the development of sliding and rotational movements. The assumption of discontinuum media changes the whole ...
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Presence of joints and fractures in rocks strongly influences the behavior of the rock mass by dividing the media into smaller units. These structures intensify the potential instability besides the development of sliding and rotational movements. The assumption of discontinuum media changes the whole analysis conditions in relation to the continuum analysis. Acquisition of geometrical and structural discontinuity data alongside their mechanical properties is of paramount importance in a rock mass analysis. Orientation, spacing, expansion, and other geometrical characteristics of the rock mass and their relative geometrical position to the studied projects influence the pattern and potential of failure. Therefore, inevitably, the first step involved in the analysis of rock mass is geometric data collection of the discontinuities as a crucial step before analysis. In this study, the traditional data collection methods in structural discontinuities with their disadvantages are reviewed. Then the discontinuity data collection based on digital image analysis is developed and applied in a case study to several walls of the Choghart iron ore mine. The results obtained show that this method has a very good accuracy in assessing the fine structures, and also it collects data in a much shorter time. This study, therefore, suggests that the proposed method can be used as a practical approach.
Exploitation
M. Jamshidi; M. Osanloo
Abstract
The block economic value (BEV) of a single-metal deposit is calculated based on the metal content and the related costs. The common methods available for calculating BEV are just based upon the profitable elements, and the effects of undesirable elements on BEV are not considered. However, in multi-element ...
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The block economic value (BEV) of a single-metal deposit is calculated based on the metal content and the related costs. The common methods available for calculating BEV are just based upon the profitable elements, and the effects of undesirable elements on BEV are not considered. However, in multi-element deposits, the effects of other elements existing in the blocks on BEV should be considered with the purpose of optimizing the blending. These elements and blending methods have considerable effects on the quality of the final product. In this paper, a new approach is introduced to determine BEV in multi-element deposit with two types of profitable and penalty elements by considering the effect of blending on BEV. Consequently, the ultimate pit limits (UPLs) will be determined based on these conditions. The developed model is tested in the Gol-e-Gohar No.2 iron-ore mine, and the mine UPLs is determined. The results obtained showed that the mineable reserve of the pit increased by 3% when the effects of both types of elements are considered. In order to investigate the effect of grade uncertainty on BEV, twenty realizations of the ore block are generated using the sequential Gaussian simulation approach. The UPLs of all the realizations are determined using the developed BEV-calculation method, and the pit limits with different probabilities of occurrence are determined. The total mineable reserve varied between 20,380 and 46,410 million tons. The exploitation of mine should start with the smallest pit (100% probability). The largest pit should be considered as a guide for surface-facility locating.
Exploitation
B. Tokhmechi; S. Ebrahimi; H. Azizi; Seyed R. Ghavami-Riabi; N. Farrokhi
Abstract
Recognition of ore deposit genesis is still a controversial challenge for economic geologists. Here, this task was addressed by the virtue of Bayesian data fusion (BDF) implementing available proofs: semi-schematic examples with two (Cu and Pb + Zn) and three (Cu, Pb + Zn and Ag) evidences. The data, ...
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Recognition of ore deposit genesis is still a controversial challenge for economic geologists. Here, this task was addressed by the virtue of Bayesian data fusion (BDF) implementing available proofs: semi-schematic examples with two (Cu and Pb + Zn) and three (Cu, Pb + Zn and Ag) evidences. The data, in current paper are just concentrations of indicated elements, were collected from Angouran’s deposit in Iran at prospecting and general exploration stages. BDF was used for discrimination between three geneses of Massive Sulfide, Mississippi and SEDEX types. Better genesis recognition with clear discrimination between the geneses was achieved by BDF as compared with earlier studies. The results showed that uncertainties were reduced from 50% to less than 30% and deposit recognition was improved greatly. Furthermore, we believe that using more properties can have a beneficial effect on the overall outcome. The comparison made between 2 and 3 properties showed that the amount of probable belonging values to any type of deposit was greater in 3 properties. It was also confirmed that using the completed information from the various stages of exploration progress can be amplified and be used for genesis recognition via BDF.
G. Kulekci; A. Osman Yilmaz; M. Çullu
Abstract
The aim of this work is to obtain recycled aggregate (RA) from construction debris in order to reduce the rapid consumption of aggregate resources and the environmental impact of these resources. In order to fulfill this aim, the density, porosity, Schmidt hardness test, uniaxial compression resistance, ...
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The aim of this work is to obtain recycled aggregate (RA) from construction debris in order to reduce the rapid consumption of aggregate resources and the environmental impact of these resources. In order to fulfill this aim, the density, porosity, Schmidt hardness test, uniaxial compression resistance, carbonation depth, and ultrasonic p-wave velocity experiments were conducted on different construction debris transported by trucks from 9 different points in Turkey. In addition, the debris samples taken were broken down to the size of the aggregate and subjected to the tests of density, porosity, moisture content, freeze-thaw, and impact resistance. As a result of the conducted experiments, the lowest mass loss as a result of freezing-thawing was in GRA with 9.36%, the highest mass loss was in ORA with 22.58%, the highest ORA average aggregate impact strength index was 21.27%, and the lowest TRA aggregate impact strength index was found to be 18.26%. İt was determined that most of the physical properties of RA obtained from the construction wreckage was within the limit values specified in the literature and that the recycled aggregates could be used instead of natural aggregate. With this work and these results, RA obtained could be used in many areas such as concrete aggregate in the construction sector, underground filling in mining, filling material in gunned concrete, and filling materials on highways.
Kwang Hyok Kim; Tok Hyong Han; Un Chol Han; Ryo Myong Hong
Abstract
This paper focuses on a study concerned with estimation of the platform motion at the lower loading station in the Trucklift slope hoisting system with varying profile of track. The TruckLift slope hoisting system is an innovative transport technology for open-pit mines, and considerably accelerates ...
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This paper focuses on a study concerned with estimation of the platform motion at the lower loading station in the Trucklift slope hoisting system with varying profile of track. The TruckLift slope hoisting system is an innovative transport technology for open-pit mines, and considerably accelerates and cheapens transport from mine. When a truck drives onto or drives off the platform at the lower loading station in the Trucklift slope hoisting system with varying profile of track, the platform motion influences the operation of the Trucklift slope hoisting system, and the configuration of inclined rope hitched to the platform is varied. The simulation result by using the ADAMS (Automatic Dynamic Analysis of Mechanical Systems) software shows that the horizontal distance between lower loading station and platform varies when a truck drives onto or off the platform and the initial horizontal distance that is the distance between lower loading station and platform when the winder is applied the brake, can be an important factor in operation of the Trucklift slope hoisting system with varying profile track.
S. Alamdari; M.H. Basiri; A. Mousavi; A. Soofastaei
Abstract
The haul trucks consume a significant energy source in open-pit mines, where diesel fuel is widely used as the main energy source. Improving the haul truck fuel consumption can considerably decrease the operating cost of mining, and more importantly, reduce the pollutants and greenhouse gas emissions. ...
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The haul trucks consume a significant energy source in open-pit mines, where diesel fuel is widely used as the main energy source. Improving the haul truck fuel consumption can considerably decrease the operating cost of mining, and more importantly, reduce the pollutants and greenhouse gas emissions. This work aims to model and evaluate the diesel fuel consumption of the mining haul trucks. The machine learning techniques including multiple linear regression, random forest, artificial neural network, support vector machine, and kernel nearest neighbor are implemented and investigated in order to predict the haul truck fuel consumption based on the independent variables such as the payload, total resistance, and actual speed. The prediction models are built on the actual dataset collected from an Iron ore open-pit mine located in the Yazd province, Iran. In order to evaluate the goodness of the predicted models, the coefficient of determination, mean square error, and mean absolute error are investigated. The results obtained demonstrate that the artificial neural network has the highest accuracy compared to the other models (coefficient of determination = 0.903, mean square error = 489.173, and mean absolute error = 13.440). In contrast, the multiple linear regression exhibits the worst result in all statistical metrics. Finally, a sensitivity analysis is used to evaluate the significance of the independent variables.
Rock Mechanics
Praveena Das Jennifer; Porchelvan P
Abstract
This paper presents a comprehensive study on the stability of the deep underground closed Kolar Gold Fields mine (3.2 km deep) under varying seismic loading conditions. The study utilized the Finite Element Method (FEM)-based Midas GTS NX software tool to conduct numerical simulations of seismic loads ...
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This paper presents a comprehensive study on the stability of the deep underground closed Kolar Gold Fields mine (3.2 km deep) under varying seismic loading conditions. The study utilized the Finite Element Method (FEM)-based Midas GTS NX software tool to conduct numerical simulations of seismic loads of varying intensities under multiple conditions of water level in the mine voids. The seismic loads applied were equivalent to the intensity of maximum mining-induced seismicity experienced in the mine. The study also examined the influence of the Mysore North Fault and its effects on the surface above the mining area. A seismic hazard vulnerability map of the mining area was developed based on the results for all simulated numerical model combinations. The results inferred that for a seismic load of PGA, 0.22 g, for fault and actual water level combination, very strong shaking and moderate potential surface damage were observed at vulnerable zones with a maximum PGA of 0.196 g and Peak Ground Velocity (PGV) of 0.49 m/s. The study highlights the importance of monitoring post-mining induced seismic activities using a dedicated microseismic monitoring system with sensors placed at the most vulnerable zone locations assessed from the numerical modelling studies carried out. Remedial measures suggested include regular dewatering of mine workings based on water accumulation and backfilling of mine voids with suitable fill material. The dynamic modelling approach using Midas GTS NX was found to be a more reliable, feasible, efficient, and simple method for assessing the stability of closed mines.
