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Упит dcterms_subject_txt:Tunneling in hard rock

1742 items

  • Blast-induced damage and its impact on structural stability of underground excavations

    Slavko Torbica, Veljko Lapcevic (2017)
    Tunneling in hard rock, rock blasting, key block theory, rock wedges

  • Estimating extent and properties of blast-damaged zone around underground excavations

    Slavko Torbica, Veljko Lapčević (2015)
    Tunneling in hard rock, rock blasting, blast-damaged zone, rock breakage by explosives

  • Development and Application of Methodology for Quantification of Overbreaks in Hard Rock Tunnel Construction

    Zoran Berisavljević, Dragoljub Bajić, Vojkan Jovičić (2023)
    A methodology for determining overbreaks in hard rock tunnel construction using the drill-and-blast technique is presented in this paper. The methodology was developed for and applied to crystalline medium- to thick-bedded limestone, but it can be used in any jointed hard rock mass. Overbreaks are inevitable in hard rock tunnelling in a low-confinement environment (shallow tunnels up to several hundred meters deep) as a result of wedge failures along unfavourably oriented discontinuities caused by blasting. It is widely accepted ...
    hard rock, drill-and-blast, geological overbreak, technological overbreak, stability criterion, discontinuity orientation, tunnel construction

  • Determination of Mechanical Properties of Altered Dacite by Laboratory Methods

    Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović (2021)
    This paper presents a methodology for determining the uniaxial and triaxial compressive strength of heterogeneous material composed of dacite (D) and altered dacite (AD). A zone of gradual transition from altered dacite to dacite was observed in the rock mass. The mechanical properties of the rock material in that zone were determined by laboratory tests of composite samples that consisted of rock material discs. However, the functional dependence on the strength parameter alteration of the rock material (UCS, intact ...
    Geology, Geotechnical Engineering, Engineering Geology
    ... the weaker rock material. Thus, the exponential trendline in Tziallas et al. [1] ends at 37% of the weaker rock material, and the ratio σci UCS/σci hard UCS = 0.47. In Z. Mohamed et al. [4], it ends at 10% of the weaker rock material and the ratio σci UCS/σci hard UCS = 0.30, while in Berisavljević ...
    ... trendline ends at 59% of the weaker rock material and the ratio σci UCS/σci hard UCS = 0.18. In the present study, the exponential trendline ends at a value of 30% of the weaker rock material and the ratio σci UCS/σci hard UCS = 0.34. After the stated values, in Tziallas et al. [1] and Berisavljević ...
    ... ić et al. [6], the ratio σci UCS/σci hard UCS is constant up to 100% of the weaker rock material, while in Z. Mohamed et al. [4] study, the σci UCS/σci hard UCS ratio decreases linearly. In the present study, the strength decrease is significantly lesser than the one determined by Z. Mohamed et ...

  • Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source

    Vladimir Živanović, Igor Jemcov, Veselin Dragišić (2022)
    Groundwater in a hard rock formation is most endangered at places where a potential source can discharge contaminants that can reach the saturated zone of an aquifer. In these circumstances, an essential tool for groundwater protection is the contamination risk map. This map is based on the integration of two maps: a hazards map, i.e., map of potential sources of contamination and a vulnerability map. The selection of a proper vulnerability method is an important task since the resulting ...
    karta rizika od kontaminacije, ranjivosti podzemnih voda, DRASTIC, EPIK, PI, COP, Nacionalni park Tara

  • Дефинисање механичких својстава алтерисаног стенског материјала лабораторијским методама

    Вељко М. Рупар (2022)
    Основни циљ овог рада је да представи методологију одређивања механичких својстава хетерогеног стенског масива који изграђују дацит (Д) и алтерисани дацит (АД), где је уочена је зона постепеног преласка од алтерисаног дацита до дацита. Механичка својства стенског масива у тој зони утврђена су на основу лабораторијских испитивања једноосне и троосне чврстоће на притисак стенског материјала композитних узорака. Композитни узорци су се састојали од дискова стенског материјала, при чему је висина дискова h дефинисала различити процентуални удео појединог стенског материјала, ...
    дацит, алтерисани дацит, једноосна чврстоћа на притисак, троосна чврстоћа на притисак, композитни узорци, механика стена, стабилност косина

  • Cutting Resistance Laboratory Testing Methodology for Underwater Coal Mining

    Vladimir Čebašek, Veljko Rupar, Stevan Đenadić, Filip Miletić (2021)
    Geology,Geotechnical Engineering and Engineering Geology
    ... of Rock/Soil Type of Rock/Soil Strength Index, fpr (MPa) Uniaxial Compressive Strength, σc (MPa) I High-strength rocks Solid and tough quartz and basalt 20 200 II Very hard rocks Porphyritic quartz, granite 15 150 III Hard rocks Granite, hard sandstone, hard iron ore 10 100 IV Relatively hard rocks ...
    ... undisturbed rock, or soil material samples, of cylindrical shape [25], typically 38 mm or more in diameter and height equal to twice the diameter of the sample. A rock or soil sample is placed in a triaxial (glass or plastic) cell, in the triaxial test, with the sample being enclosed in a rubber membrane ...
    ... block-shaped rock material samples. Consequently, the testing method is most used for determination of the cutting resistance of the material to be excavated. 2. Coal Mining in Underwater Pit “Kovin” Exploration work in the coal and gravel deposit area began in 1976, while coal exploita- tion began in 1995 ...

  • Simpson's rule application for experimental determining parameters of rock mass oscillation equation at limestone

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Branko Gluščević, Luka Crnogorac (2021)
    By its form, the use of explosives has a destructive character. However, energy of chemical explosives is tamed and perfected in many effects, so that is developed a series of activities which work is unthinkable without the use of explosives. In mining industry, explosives are most commonly used for exploitation in hard rock mass. Thereby, large amounts of explosives can be used, especially for mass blasting. The application of large amounts of explosives gives auspicious techno – economic indicators ...
    working environment, seismic effects of blasting, oscillation velocity, rock mass oscillation equation, Simpson’s rule

  • Analiza seizmičkog dejstva eksplozije pri miniranju na primeru izrade tunela Golubac kod Golupca

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac (2022)
    Savremeno rudarstvo, a pogotovo masovna eksploatacija metaličnih ležišta, ne bi se mogla zamisliti bez primene eksploziva. Rudarstvo je privredna grana, gde su eksplozivi našli najširu primenu za eksploataciju čvrstih mineralnih sirovina. Primena energije eksploziva dovodi do poboljšanja tehničkoekonomskih pokazatelja pri eksploataciji mineralnih sirovina, ali i do pojave negativnih efekata koji prate radove na miniranju. Eksplozivni materijali u rudarstvu, geologiji i drugim delatnostima, svojim dejstvom narušavaju prirodnu sredinu u vidu drobljenja, razbacivanja komada stene, vazdušnih udara, pojave sezmičkih efekata, pojave ...
    miniranje, seizmičko dejstvo, brzina oscilovanja stenske mase, kriterijumi ocene seizmičkog dejstva

  • Sensitivity analysis of rock mass parameters estimate influence on decline support design using NATM

    Slavko Torbica, Veljko Lapčević, Wang Gang, Nemanja Đokić, Miodrag Duranović (2019)
    Rock mass, Tunneling, NATM, GSI, Stress, Cukaru Peki, Bor

  • Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac (2023)
    ... point r increase in the same or approximately the same ratio, the rock mass oscillation velocity V remains the same [6]. Here we cite second way of rock mass oscillation velocity equation derivation. If, in blasting in the specific environment, the relative increment in rock mass oscillation velocity ...
    ... determine the value of the parameter K in advance for an adopted value of the parameter m in the interval from 1 — 2, as has been applied in model 5. In this way, a new simplified formula has been obtained for determining the rock mass oscillation velocity equation in which only parameter K is calculated ...
    ... 2 V,OS NM +V TV 3 Q) 3. ROCK MASS OSCILLATION VELOCITY EQUATION Rock mass oscillation velocity equation defines velocity alteration of rock mass oscillation depending on distance, explosive amount, properties of rock material and blasting method. The equation, defined in this way, offers the possibility ...

  • Mesozoic carbonate rocks in Serbia used as dimension stone

    Vesna Matović, Tijana Vojnović Ćalić (2016)
    The building industry in Serbia uses, to a great extent, imported natural stone for architectural purposes. The significance of local deposits, particularly limestones, is not adequately perceived despite the country’s abundance of these valuable resources. Therefore, this study focuses on Serbia’s Mesozoic carbonate rocks, specifically on the deposits of four selected quarries: Klisura, Skrzut, Struganik, and Tisnica. The quality and prospects of the application of these limestones has not yet been the subject of a detailed, comprehensive investigation. Therefore, ...
    Ukrasni kamen, Mezozoik, Krečnjak, Srbija, Petrografija, Fizičko-mehanička svojstva
    ... 12.5 to 25.5 m. In geological terms, the rock mass is known as “Bulog limestone”. It belongs to the Medium Triassic-Late Pelsonian to Middle/Late Illyrian age (Pan- tić-Prodanović 1996; Sudar et al. 2013). The Skrzut quarry of natural stone was opened in 1960. It is situated in western Serbia ...
    ... they have decreased by 20-27 %. A small decrease in compressive strength of the Struganik limestone (after the frost test), compared to the expected decrease in strength in water saturated sam- ples, may be due to the heterogeneity of the rock mass, 1.e., tested samples. All observed limestones ...
    ... 1b). The limestone ore body is elongated in a NW-SE direction, with variable thickness of 6.95-34.0 m (Lazarević 1994). The rock mass is built of Upper Cretaceous limestone, which belongs to the Cenomanian age (Dimitrijević 1996). Tectonically, the rock mass is fragmented into blocks by a system ...

  • English for Geology Students. 2

    Lidija Beko (2023)
    Engleski jezik
    ... the intrusion of molten granite batholiths into surrounding rock, both through heat and by forcing very hot liquids with high mineral contents into the rock. The crystallisation that occurs with cooling results in cracks in the rock being filled with mineral veins or – when the veins are grouped ...
    ... synonyms: amid, amidst astonishing adjective used to describe something amazing or hard to believe; synonyms: amazing, jolting, jaw-dropping; antonyms: mundane, ordinary, usual astonishingly adverb in a rather surprising manner; synonyms: amazingly, surprisingly, unexpect- edly; antonyms: ...
    ... of the basic rock types – igneous, sed- imentary and metamorphic – can be host to mineral ore deposits: accumulations of minerals with a sufficiently high concentration of the desired end product to make extraction and processing financially viable. This property is also described in terms of the ...

  • Pre-failure deformation monitoring as rockfall prediction tool

    Miloš Marjanović, Biljana Abolmasov, Zoran Berisavljević, Marko Pejić, Petko Vranić (2021)
    General Engineering
    ... Serbia milos.marjanovic@rgf.bg.ac.rs Abstract. In this article, we are elaborating an example of predictive rockfall assessment by using Terrestrial Laser Scanning (TLS) in monitoring a road cut, hosted in flysch rock formation, near Ljig in Serbia. A sequence of rockfall events from 2013-2019 ...
    ... example will be presented, while the entire rock slope will be analyzed in greater depth in the near future. 1.1. Related research There is a substantial amount of scientific literature, papers, books, etc. related to the field of rock slope monitoring. In addition, commercial industries, especially ...
    ... point, as potentially valuable information in rock slope analysis (surface rock type, weathering degree water content might be correlated). These angular and distance measurements allow accurate reconstruction of each target point spatial coordinates (X,Y,Z) in respect to the optical center of the ...

  • Primena programa UVSZ pri zaštiti od miniranja

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac, Rade Tokalić (2021)
    Primena energije eksploziva tj. miniranje, predstavlja osnovni način eksploatacije čvrstih mineralnih sirovina u rudarstvu. Miniranjem se postižu vrlo povoljni tehnoekonomski pokazatelji, koje nažalost prate i negativni efekti miniranja. U cilju zaštite životne sredine potrebno je za svaku radnu sredinu odrediti jednačinu oscilovanja stenske mase pri miniranju. Ova jednačina definiše promenu brzine oscilovanja stenske mase u zavisnosti od rastojanja, količine eksploziva, uslova izvođenja miniranja i geoloških karakteristika stenske
    Program UVSZ, miniranje, potres, zaštita životne sredine
    ... the main way of hard raw materials exploitation in mining industry. Very favorable techno-economic indicators are achieved by blasting, which are followed by negative effects of blasting unfortunately. In order to protect the environment, it is necessary to determine the rock mass oscillation ...
    ... represents the main way of hard raw materials exploitation in mining industry. Very favorable techno-economic indicators are achieved by blasting, which are followed by negative effects of blasting unfortunately. In order to protect the environment, it is necessary to determine the rock mass oscillation equation ...
    ... environment during blasting. This equation defines the change of rock mass oscillation velocity depending on distance, explosive amount, conditions of blasting and geological characteristics of rock mass. Oscillations of the particles of rock mass at terrain are felt as shock. Based on application of ...

  • Preparation of Multimedia Document “YU Rock Scene”

    Milena Obradović, Aleksandra Arsenijević, Mihailo Škorić (2017)
    SUMMARY: This study will present the preparation process of a multimedia document entitled YU ROCK SCENE in which participants were senior students of undergraduate studies of the Department of Library and Information Science at the University of Belgrade Faculty of Philology during the academic year 2014/2015, as a part of the subject Multimedia Documents. This study gives an overview of the historical development of rock and roll in the territory of the former Yugoslavia, rock scene in Yugoslav republics, ...
    multimedia document, library science, information science, rock and roll, music, Yugoslavia
    ... influenced by the hippy movement, but then branching of rock music into sub-branches began, giving rise to hard rock, progressive rock, art rock, jazz, blues and others. At the end of that decade, punk appeared (under the influence of British and American punk bands such as The Sex Pistols, The Clash, The ...
    ... others. 2.4 YU Rock Scene in Bosnia and Herzegovina In Yugoslavia, Bosnia and Herzegovina was a fertile soil for the development of pop and rock music, which was especially evident in Sarajevo, Travnik, Bugo- jno and Bihać. One of the first rock groups in these territories was the group In- deksi, to ...
    ... directions developed in rock and roll music: country pop rock (com- bination of ethno sound and rock style) and the western, mostly Anglo-American rock. Unlike the world rock scene whose texts were a powerful means of propaganda against wars and class conflicts, original domestic rock texts had visual and ...

  • Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series

    Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić (2021)
    Underground mining engineers and planners in our country are faced with extremely difficult working conditions and a continuous shortage of money. Production disruptions are frequent and can sometimes last more than a week. During this time, gate road support is additionally exposed to rock stress and the result is its progressive deformation and the loss of functionality of gate roads. In such an environment, it is necessary to develop a low-cost methodology to maintain a gate road support system. ...
    deformacije podgrade, lasersko skeniranje, višekanalna singularna spektralna analiza, prognoza, klasterisanje fuzzy vremenskih serija
    ... interferometry to support the management of each phase of tunneling. Qian Zhang et al. [8] made a numerical simulation for advanced displacement of tunnel with weak and broken surrounding rock in order to reveal the adjusting process of displacement in the main parts of a tunnel. Grossauer et al. [9] developed ...
    ... gate road support is exposed to the rock stress much longer than is the case with the application of modern mechanized methods. In such a production environment, the maintenance of the gate road stability is almost impossible and is per- formed in an unsystematic way. In order to improve such a difficult ...
    ... gate road support is exposed to the rock stress much longer than is the case with the application of modern mechanized methods. In such a production environment, the maintenance of the gate road stability is almost impossible and is per- formed in an unsystematic way. In order to improve such a difficult ...

  • Deformation and permeability of cement stone of diferent composition in hard formations

    Bošković Zvonimir, Čebašek Vladimir, Nuhanović Sanel, Crnogorac Jovana (2014)

  • Deformation and permeability of cement stone of diferent composition in soft to medium hard formations

    Bošković Zvonimir, Čebašek Vladimir, Nuhanović Sanel, Crnogorac Jovana (2014)

  • Anisotropic grossular–andradite garnets: Evidence of two stage skarn evolution from Rudnik, Central Serbia

    Bojan Kostić, Danica Srećković-Batoćanin, Petyo Filipov, Pavle Tančić, Kristijan Sokol (2021)
    This paper presents LA-ICP-MS data for garnets from the Rudnik skarn deposit (Serbia), which range from Grs45–58Adr40–52Alm2–3 in the core and Adr70–97Grs2–29Sps1 in the rim displaying anisotropy and zoning. In spite of wide compositional variations the garnets near the end-member of andradite (Adr > 90) are generally isotropic. Fe-rich rims exhibit LREE depletion and flat HREE pattern with weak negative Eu anomaly, including higher As and W contents. On the other side, the Fe-poorer core shows flat REE pattern ...
    grandite, garnets, skarn, Rudnik
    ... conditioned by Eu2+ in reduction conditions. The observed variations in optical features and garnet chemistry are the results of their two-stage evolution. The first stage and period of garnet growth is probably buffered by mineral dissolution and reactions in the country rock. The second stage is ...
    ... oscillatory zones, res pec- tively. The studied garnets have grown in a typical skarn rock, rich in ore minerals. Major and trace element zonal distributions reflect primarily the compositional heterogeneity of the proto- lith, changes in fluid composition during garnet growth, as well as, reactions ...
    ... anisotropic core and isotropic rim. Recrystallized calcite with rare epidote grains, was matrix in the protolith rock. Epidote grains are optically zoned and anhedral. Chlorite often appears in radial forms and displays Berlin blue interference colours. The last constituent, quartz, is a terrigenous ...