Nauki Ścisłe i Nauki o Ziemi

Archives of Mining Sciences

Zawartość

Archives of Mining Sciences | 2020 | vol. 65 | No 1 |

Abstrakt

The article presents an assessment of the value of the post-industrial landscape in the town of Rydułtowy using a comprehensive approach. It includes: 1) Defining the scope of the study taking into account regional context; 2) Inventory of mining facilities; 3) Desk study; 4) Field research and interviews; 5) Value assessment and guidelines. For assessing the value of the post-mining landscape the Architectural-Landscape Units & Interiors method was selected. The usefulness of the proposed method for the post-industrial landscape assessment was demonstrated using the case of Rydułtowy, a mining town. This article also describes the history of the mining activities in the town of Rydułtowy. The significance of the more than 200 years of mining on the growth and expansion of the town as well as its identity is reviewed. Special attention is given to the history and the present state of the most prominent element of the landscape, namely the cone-shaped landfill – Szarlota. The guidelines resulting from applying the proposed landscape value assessment are useful for a number of stakeholders and future activities planned for both the cone heaps and the mining plant.

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Autorzy i Afiliacje

Anna Ostręga
Marek Cała

Abstrakt

The structural system of a multiple strip-shaped pillar-roof is common in underground mine exploitation, and research on its mechanics and micro/macroeconomics is meaningful for utilizing strip-shaped pillar resources. A general model of the structural system of a multiple strip-shaped pillar-roof was established, the deformation mechanism of the model was analysed by material mechanics, and the deflection curve equations of the model were obtained. Based on the stress strain constitutive relation of the strip pillar and cusp catastrophe theory, the nonlinear dynamic instability mechanism of the structural system of a multiple strip-shaped pillar-roof was analysed, and the expressions of the pillar width for maintaining the stability of different types of structural systems were derived. The benefits of different structural systems were calculated using micro/macroeconomic theory, the type of the structural system was determined, and different recovery schemes were obtained. Theoretical application research was applied to a large manganese mine, and the results demonstrate that no pillar recovery was needed in 2016, a 9-m wide artificial pillar could be built to replace a pillar in 2017, and the construction of 14-m wide artificial pillars can be conducted in 2018.

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Autorzy i Afiliacje

Qingfa Chen
Shiwei Wu
Fuyu Zhao

Abstrakt

The aim of the study was to develop an assessment methodology for the temperature of the surface of the friction pair during the braking for mine hoists. During the braking process, the work of friction is transformed into heat at the level of friction surfaces, and in case high temperatures are reached, the friction coefficient is influenced negatively, thus the risk of braking failure exists. In the first part of the study we measured the temperature of the friction surfaces for a particular case of hoist in real braking conditions. In the second part of the study is presented a theoretical model for the calculation of the temperatures resulted in the braking process for the hoist equipped with shoe brakes. The theoretical model for calculation was simulated numerically for a particular case in real braking conditions. Based on the conclusions resulted after the study, a series of hypotheses and recommendations for adjusting the control of the process parameters have been given out, in order to avoid the excessive heating of the brakes of the hoists and, respectively, their improved safety, maintenance and availability.

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Autorzy i Afiliacje

Miorita Ungureanu
Nicolae Stelian Ungureanu
Marius Cosma

Abstrakt

Subnetwork with two nodes shared with entire ventilation network can be separated as its part. For the network under common ventilation conditions, one of these nodes will become the subnetwork starting node, while the other will be the subnetwork end node. According to the graphs theory, such a piece of the network can be considered as a subgraph of the graph representing the entire ventilation network. A special feature of that subgraph is lack of predecessors of the subnetwork starting node and lack of successors of the subnetwork end node. Ventilation district of a mine may be often treated as a subnetwork. Vicinity is a part of the network which is not separated as subnetwork. In the case of a ventilation district its vicinity forces air flow through the district. The alternative characteristic curve of the vicinity can therefore be compared to the characteristics curve of a fictional fan that forces the airflow in the district.

The alternative characteristics (later in the text: the characteristics) of the vicinity of the ventilation district in an underground mine strongly influence air quantity and therefore play a crucial role in the reduction of methane, fire and thermal hazards. The role of these characteristics and proper selection of their approximating function were presented in the article.

The reduction of resistance of an intake stopping (having influence on entire resistance of a ventilation district) produces increased airflow in the district. This changes of airflow in the district caused by a variation in internal resistance (e.g. by opening an internal regulation stopping) depends on the characteristic of the vicinity of the district. Proper selection of its approximating function is also important for this matter.

The methods of determination of the alternative characteristic curve of the district vicinity are presented. From these procedures it was possible to obtain the results of air quantities and differences in isentropic potentials between an inlet and an outlet to/from the ventilation district. Following this, the characteristics were determined by graphic and analytic methods. It was proved that, in contrast to flat vicinity characteristics, steep ones have a smaller influence on the airflow modification in the district (which are caused by a regulation of the district resistance). The characteristic curve of the vicinity determines the ability to regulate air quantity and velocity in the district.

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Autorzy i Afiliacje

Grzegorz Pach

Abstrakt

Stemming plugs are one of the widely used accessory in surface mining operations. Stemming plugs assist conventional stemming material in gas retention and help in better fragmentation and explosive utilization. Effective use of the stemming plugs results in economic benefits and enhance the efficacy of the project. Economic and productive viability of stemming plugs have been conducted in depth by different researchers. Addition of stemming plugs to a new system requires ergonomic challenges for operators conducting drilling and blasting operation. Induction of a newer product in already established system is subject to overall positive feedback. This work investigates ergonomics of three different stemming plugs introduced to a limestone quarry in Pakistan. The stemming plugs were evaluated based on extra time needed, workers feedback, failures during operation, recovery time after failure and number of extra equipment required to carry out the operation. Points based matrix was established with likeliness of each plug and based on overall scores stemming plug 1 was most acceptable followed by stemming plug 3. Stemming plug 2 was disliked by operation and did not reach the level of acceptability of operators. This work will help stemming plug making industry in adapting to best practices by incorporating ergonomics of plugs in designing. Literature shows no previous work on ergonomics of stemming plugs.

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Autorzy i Afiliacje

Atta Ur Rehman
Muhammad Zaka Emad
Muhammad Usman Khan

Abstrakt

The mine seals in coal mines with a good impact resistance and air tightness are mainly used to isolate abandoned mining areas from active workings. For one thing, it can prevent the leakage of harmful gases, such as toxic gas from abandoned areas. For another, once an underground mine explosion happens, it can effectively block the spread of the explosion between the abandoned mining areas and the active workings. Hence, it is of great significance to study the explosion-proof performance and mechanical properties of the mine seals. First of all, the effect of slotting on the stability of the seals in coal mines under explosion load was explored in this study. By numerical simulations, the mechanical response characteristics of the seals with or without cutting a slot under the explosion load were compared in detail. The results show that slotting improved the stress concentration at the contact surface of surrounding rock by transferring partial impact received by mine seals to the surrounding rocks, thus, to achieve the effect of buffering explosion impact. Besides, such effect will be enhanced with increasing cutting depth into rock, and will stabilize when the depth is 20 cm. On this basis, the mechanical properties and damage of the seals constructed by different materials (standard brick and #C40 concrete) under the explosion load were compared. It was found that once a slot was set, the maximum deformation of the concrete seal was reduced, while the maximum deformation of the brick seal increased. Since the non-deformability of the concrete seal is obviously stronger than that of the brick seal, with the impact resistance stronger than that of the brick seal, the concrete seal is more suitable for slotting. Moreover, the damage of the seals in underground coal mines under the strata ground pressure was studied; the results of which show that the damage state under the ground pressure can be divided into 3 levels, i.e. no damage, minor damage and rapid development of damage. Meanwhile, it was found that the prestressed structure formed by the ground pressure at the level of no damage can enhance the protective effect of the seals in coal mines. However, when the ground pressure was further developed, the seal itself was destroyed and the protective effect was lost. In addition, the influence of roof to floor moving convergence, a deformation parameter of the roadway, on the seals was also investigated. The results show that the ground pressure and roof-to-floor convergence act on the seals in coal mines in the same way, thus roof to floor moving convergence can replace the ground pressure to analyze other related mechanical properties of the seals in coal mines in the future researches.

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Autorzy i Afiliacje

Jianwei Cheng
Wanting Song
Yi Jing
Xixi Zhang
Marek Korzec
Marek Borowski
Yue Wang

Abstrakt

The longwall mining system with fall of the roof is still the most common hard coal extraction system in Polish mining. Its utilization for selective coal seams’ mining results in the development of post-extraction gobs at different depths. Methane desorption phenomena from the coal seams in the stress release zones and migration of gas towards the area of operations, result in methane accumulating also after completion of coal exploitation. Methane which is not exploited from the gobs can migrate directly to the atmosphere e.g. through overlying layers, faults, workings or directly via an operated ventilation grid of an adjacent coal mine – contributing to the Greenhouse Gas effect. One of the methods to capture methane (Abandoned Maine Methane) from abandoned coal mines is to drill vertical wells through several post-extraction gobs from the surface.

This paper presents the results of drilling operations at the AGH-Wieczorek-1 well, where first time in Poland, down-the-hole-hammer (DTH) with casing-while-drilling (CwD) technology were used to drill through several post-extraction gobs. The AGH-Wieczorek-1 well with 440.0 m MD was successfully drilled without any complications. Finally, three post-extraction gobs and two coal seams were drilled. Additionally, results from drillability tests, which were performed during drilling operations, are presented.

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Autorzy i Afiliacje

Jakub Siemek
Jan Macuda
Łukasz Łukańko
Jacek Hendel

Abstrakt

Geographical Information Systems have become essential tools for land analysis and the subsequent decision making in many fields of human activity. In the field of mining, GIS applications have appeared in ore deposit modelling, environmental pollution, or planning of mining spaces. In this research, the powerful multicriteria tools of GIS platforms have been applied for the determination of an index that has been called “Exploitability Index”. This index allows analyzing a series of outcrops of industrial aggregates, to help in the selection of the most adequate one to be enhanced from a mining approach. The multicriteria analysis has been applied for its determination, and as a result of this research, a model is proposed. The main criteria that condition the decision have been established in this model, along with their subsequent hierarchization and their weighting. The proposed model is applied to a specific case: the analysis of a series of outcrops of industrial aggregates (ophites) in Cantabria, Spain. After defining the Exploitability Index for those ophitic outcrops, it has been observed that the only deposit that has been classified as very suitable for its exploitation is the only one that has been really exploited, supporting the proposed methodology.

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Autorzy i Afiliacje

Gema Fernández-Maroto
Julio Manuel de Luis-Ruiz
Raúl Pereda-García
Beatriz Malagón-Picón
Rubén Pérez-Álvarez

Abstrakt

The article attempts to transfer information from the Point Nuisance Method (PNM) used in Poland in the issue of protection of buildings in mining areas, to the system of inference based on Bayesian formalism. For this purpose, all possible combinations occurring in PNM were selected. The number of numerically generated patterns was 6,718,464 cases. Then, based on Python package Scikit-Learn, a classification model was created in the form of the Naïve Bayes Classifier (NBC). The effectiveness of three methods used to build this type of decision-support system was analysed, from which the Categorical Multinomial Naive Bayes (CMNB) approach was finally selected. With the created classifier, its properties were verified in terms of quality of classify and generalization. For this purpose a general approach was used, analysing the level of accuracy of the model in relation to training and teaching data, and detailed, based on the analysis of the confusion matrix. Additionally, the operation of the created classifier was simulated to determine the optimal Laplace smoothing parameter α. The article ends with conclusions from the carried out calculations, in which an attempt was made to answer the question concerning potential reasons for incorrect classification of the created CMNB model. The discussion ends with a reference to the planned research, in which, among other things, the use of more complex Bayesian belief networks (BBN) is planned.

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Autorzy i Afiliacje

Janusz Rusek

Abstrakt

In this study, the compressive deformation of crushed sandstone was tested using a crushed rock deformation-seepage test system, and the effects of various factors, including crushed rock grade, grade combination, water saturation status, and stress loading method (i.e., continuous loading or cyclic loading and unloading), on the compressive deformation of crushed sandstone was analyzed from four perspectives including stress-strain, bulking coefficient, deformation mechanism and energy dissipation. The results indicate that the stress-strain relations of crushed sandstone are closely associated with all factors considered, and are well represented by exponential functions. The strain observed for a given applied stress increased with increasing crushed rock grade throughout the loading period. Crushed sandstone grades were combined according to a grading index (n), where the proportion of large-grade rocks in the sample increased with increasing n. The bearing capacity of a water-saturated crushed sandstone sample with n = 0.2 was less than that of an equivalent dry sample for a given applied stress. The stress-strain curve of a water-saturated crushed sandstone sample with n = 0.2 under cyclic loading and unloading was similar to that obtained under continuous loading. Observation and discovery, the deformation mechanism of crushed sandstone was mainly divided into four stages, including crushing, rupture, corner detachment and corner wear. And 20% of the work done by testing machine is used for friction between the crushed sandstone with the inner wall of the test chamber, and 80% is used for the closing of the void between the crushed sandstone, friction sliding, crushing damage.

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Autorzy i Afiliacje

Yanan Sun
Peisen Zhang
Wei Yan
Fenqian Yan
Junda Wu

Abstrakt

Coal is the main energy source in China, but its underground mining causes surface subsidence, which seriously damages the ecological and living environments. How to calculate subsidence accurately is a core issue in evaluating mining damage. At present, the most commonly used method of calculation is the Probability Integral Method (PIM), based on a normal distribution. However, this method has limitations in thick topsoil (thickness > 100 m), in that the extent of the calculated boundary of the subsidence basin is smaller than its real extent, and this has an undoubted impact on the accurate assessment of the extent of mining damage. Therefore, this paper introduces a calculation model for surface subsidence based on a Cauchy distribution for thick topsoil conditions. This not only improves the accuracy of calculation at the subsidence basin boundary, but also provides a universal method for the calculation of surface subsidence.

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Autorzy i Afiliacje

Yue Jiang
Rafał Misa
Krzysztof Tajduś
Anton Sroka
Yan Jiang

Abstrakt

Finding effective ways to efficiently drive roadways at depths over 1 km has become a hotspot research issue in the field of mining engineering. In this study, based on the local geological conditions in the Xinwen Mining Area (XMA) of China, in-situ stress measurements were conducted in 15 representative deep roadways, which revealed the overall tectonic stress field pattern, with the domination of the horizontal principal stresses. The latter values reached as high as 42.19 MPa, posing a significant challenge to the drivage work. Given this, a comprehensive set of innovative techniques for efficiently driving roadways at depths over 1 km was developed, including (i) controlled blasting with bidirectional energy focusing for directional fracturing, (ii) controlled blasting with multidirectional energy distribution for efficient rock fragmentation, (iii) wedge-cylinder duplex cuts centered on double empty holes, and (iv) high-strength supports for deep roadways. The proposed set of techniques was successfully implemented in the –1010 west rock roadway (WRR) drivage at the Huafeng Coal Mine (HCM). The improved drivage efficiency was characterized by the average and maximum monthly advances of 125 and 151 m, respectively. The roadway cross-sectional shape accuracy was also significantly improved, with the overbreak and underbreak zones being less than 50 mm. The deformation in the surrounding rock of roadway (SRR) was adequately controlled, thus avoiding repeated maintenance and repair. The relevant research results can provide technical guidance for efficient drivage of roadways at depths over 1 km in other mining areas in China and worldwide.

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Autorzy i Afiliacje

Wei Zhang
Jia-Jia Tang
Dong-Sheng Zhang
Lei Zhang
Yuyan Sun
Wei-Sheng Zhang

Abstrakt

Monitoring the stress change of bolt and knowing the anchoring condition in a reasonable and effective way, accurately, can effectively prevent tunnel accident from breaking out. The stress of rock mass around the roadway is usually transferred to the anchor rod in the form of axial load, so it is of great significance to study the axial load of the bolt. In this paper, a full size anchoring and drawing experiment system was designed and established, innovatively, which realized the pull-out test of 2.5 m prestressed end Anchorage and the full-length Anchorage by using the new resin anchorage agent under vertical and horizontal loads. Through the application of fiber Bragg grating (FBG) sensing technology to the test of full-scale anchor rod, the axial force distribution characteristics of the end Anchorage and the full-length Anchorage anchor rod were obtained under the action of pre-tightening torque and confining rock pressure. The comparison indicates that the proportion of high stress range accounts for only 17.5% and the main bearing range is near the thread end of anchor rod, the proportion of main bearing range of end Anchorage is 83.3%, and the feasibility of FBG force-measuring anchor rod is verified in the field. The research results have certain reference value.

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Autorzy i Afiliacje

Tuo Wang
Jucai Chang
Peng Gong
Wenbao Shi
Ning Li
Shixing Cheng

Redakcja

Editor-in-Chief

Prof. Antoni Tajduś, AGH University of Science and Technology, Krakow

Associate Editor

Prof. Jakub Siemek, AGH University of Science and Technology, Krakow, Poland

Section Editors

Dr Katarzyna Cyran, AGH University of Science and Technology, Poland

Prof. Wacław Dziurzyński, Strata Mechanics Research Institute, Polish Academy of Sciences, Krakow, Poland

Associate prof. Jerzy Krawczyk, Strata Mechanics Research Institute, Polish Academy of Sciences

Associate prof. Krzysztof Tajduś, Strata Mechanics Research Institute, Polish Academy of Sciences, Poland

Editorial board

Prof. Piotr Czaja, AGH University of Science and Technology, Krakow, Poland

Prof. Józef Dubiński, Central Mining Institute, Katowice, Poland

Prof. Stanisław Nagy, Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Prof. Stanisław Prusek, Central Mining Institute, Katowice

Prof. Tadeusz Słomka, AGH University of Science and Technology, Krakow

Prof. Ryszard Tadeusiewicz, AGH University of Science and Technology, Krakow

Prof. Wacław Trutwin, Strata Mechanics Research Institute, Polish Academy of Sciences, Krakow

Prof. Andrew K. Wojtanowicz, Louisiana State University, Baton Rouge, USA

Chairman of International Advisory Board

Prof. Marek Cała, AGH University of Science and Technology, Krakow, Poland

Members of International Advisory Board

Prof. Leandro R. Alejano, Universidad de Vigo, Spain

Prof. Kashy Aminian, West Virginia University, USA

Prof. Timothy Carr, West Virginia University, USA

Prof. Eleonora Widzyk-Capehart, University of Chile, Chile

Prof. Pedro Riesgo Fernández, University of Oviedo, Spain

Prof. Mihaly Dobróka, University of Miskolc, Hungary

Prof. Sevket Durucan, Imperial College London, United Kingdom

Prof. Aidarkhan Kaltayev, al-Frabi Kazakh State University, Almaty Kazachstan

Prof. Evgeny I. Križanivskij, National Oil and Gas University of Ukraine, Ivanofrankovsk, Ukraine

Prof. Ian Lowndes, University of Nottingham, Nottingham, United Kingdom

Prof. Henryk Marcak, AGH University of Science and Technology, Krakow

Prof. Marian Marschalko, VŠB-Technical University of Ostrava,Czech Republic

Prof. Stefan Miska, University of Tulsa, Tulsa, USA

Prof. Pierpaolo Oreste, Politecnico di Torino, Italy

Prof. Durga Charan Panigrahi, Indian School of Mines, Dhanbad, India

Prof. Tadeusz Patzek, The University of Texas at Austin, USA

Prof. Lucjan Pawłowski, University of Technology, Lublin

Prof. Genadyi G. Pivnyak, National Mining University of Ukraine, Dniepropetrovsk, Ukraine

Prof. Pekka Särkkä, Helsinki University of Technology Helsinki, Finland

Prof. Anton Sroka, Strata Mechanics Research Institute of the Polish Academy of Sciences, Krakow

Prof. Stanisław Stryczek, AGH University of Science and Technology, Krakow

Prof. Vlad Ulmanu, University Petroleum-Gas of Ploiesti, Romania

Prof. Jann Rune Ursin, University of Stavanger, Norway

Prof. Jan Wachowicz, Central Mining Institute, Katowice

Prof. Yaroslavl Vasyuchkov, Russian Academy of Natural Sciences, Moscow, Russia

Prof. Isik Yilmaz, Cumhuriyet University Sivas, Turkey

Kontakt

Mrs. Marta Bitner

Instytut Mechaniki Górotworu PAN

ul. Reymonta 27, 30-059 Kraków

Phone: +48 12 637 62 00 w. 58

Email: ams@img-pan.krakow.pl

Instrukcje dla autorów

General information

It is essential for us that authors write and prepare their manuscripts according to the instructions and specifications listed below. Therefore, authors are strongly encouraged to read these instructions carefully before preparing a manuscript for submission.

Archives of Mining Sciences (AMS) is concerned with original research, new developments and case studies in all fields of mining sciences which include:

- mining technologies,

- stability of mine workings,

- rock mechanics,

- geotechnical engineering and tunnelling,

- mineral processing,

- mining and engineering geology,

- mining geophysics,

- mining geodesy

- ventilation systems,

- environmental protection in mining,

- economical aspects in mining,

- mining machine science.

Papers are welcomed on all relevant topics and especially on theoretical developments, analytical methods, numerical methods, rock testing, site investigation, and case studies.

AMS publishes research and review articles, technical notes.

Papers suitable for publication in AMS are those which:

- contain original work - the main result is not published elsewhere neither by the authors nor somebody else, and is not currently under consideration for publication in any other journal,

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References

A bibliography without numbering, arranged alphabetically according to the author’s last name, should include all positions referring in the text. In case of more than one article from the same year, the articles should be differentiated as follows: 1985a, 1985b, etc. The following order is required: last name and initials of all co-authors, year, title, type of publications, (journal, conference material, collection of monograph articles, unpublished texts) with the page numbers used.

Quoting references

Name(s) of the author(s) should be provided in parentheses. e.g.: (Brandt, 1993), (Crosdale & Beamish, 1994). (Dziurzynski et al., 1990) in the case of one, two or more than two authors, respectively. If the name(s) of the author(s) is included in the text, then the reference should be cited as follows e.g.: „According to Brandt (1993)...”

Example of bibliography.

Brandt, J., 1993. Neuere Erkentnisse auf dem Gebiet der Gasausbruchprognose. Glückauf Forschungshefte 54, 5, 228-233.

Crosdale, P. J., Beamish, B.B., 1994. Methane sorption studies at South Bulli (NSW) & Central (QLD) collieries using a high-pressure microbalance. 28 Newcastle Symposium on „Advances in the study of Sydney Basin”, Newcastle, NSW, Australia, 15-17 April, 118-125.

Dziurzynski, W., Trutwin W., Tracz J., 1990. Symulacja komputerowa przepływu powietrza i gazów powyrzutowych w sieci wentylacyjnej kopalni. J. Litwiniszyn (Ed.), Górotwór jako ośrodek wielofazowy; Wyrzuty skalno-gazowe. Wydawnictwo AGH, Kraków, Vol. II, 743-758.

Lama R. D., Bodziony, J., 1996. Outbursts of gas, coal and rock in underground mines. Publisher Lama & Associates, 130 Brokers Road, Mt. Pleasant, NSW 2519, Australia.

Nekrasovski, Ya. E., 1951. Razrabotka plastov podverzhennykh vnezapnym vybrosam ugla i gaza. Ugletekhizdat, Moskva.

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