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Упит dcterms_subject_txt:Tunneling in hard rock

1819 items

  • Multiple-Criteria Decision-Making in Mine Development Planning

    Sanja Bajić (2023)
    The Borska Reka ore deposit is an experimental location where developed methodologies have been applied. It is the largest ore body within the Bor mining complex, which has been the subject of numerous studies and analyses for more than three decades. The paper focuses on the application of FAHP and the VIKOR method to address ranking of alternatives and select the optimal mining method by means of fuzzy multicriteria optimization.

  • 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 ...

  • Evaluation And Perspectives Of Underground Coal Mines In Serbia

    Vladimir Milisavljević, Milena Lekić, Ivica Ristović, Vojin Čokorilo, Aleksandar Cvjetić (2017)
    ... will be used in AHP. For this purpose following criteria are selected: • Reserves, score is given in relation to existing A and B amounts of reserves (criteria C1); • Geological conditions, such as faulting, seam inclination, block size, seam variation, roof and floor conditions, rock pressure and ...
    ... ranged from 1 to 5 in relation to actual value of parameter or parameters. Due to restricted number of pages, scores of selected criteria required for AHP are given in Table 2. To provide more complete picture, coal productions achieved in period 2010-2015 in these mines are given in Table 3. Table ...
    ... one of the major coal producers in Europe, with over 38 Mt of coal per year. But most of this production is achieved in lignite open cast mines, which in 2016 produced 37.6 million tonnes [1]. On the other hand, combined production of all underground coal mines in Public Company for Underground ...

  • Simple 2D gravity–density inversion for the modeling of the basin basement: example from the Banat area, Serbia

    Ivana Vasiljević, Snežana Ignjatović, Dragana Đurić (2019)
    We have developed a technique to calculate lateral density distribution of the sedimentary basin basement by combining linear gravity–density inversion and 2D forward modeling. The procedure requires gravity anomaly data, depth-to-basement data and density data for the sediments (density–depth distribution). Gravity efect of density variations in the basement was extracted from the total gravity anomaly by removing the joint efect of the sediments with vertical density variations and homogeneous basement of average density contrast (calculated by 2D modeling). Gravity ...
    funkcije raspodele gustine, lateralna raspodela gustine, karta gustine podloge

  • Preliminary regional landslide susceptibility assessment using limited data

    Igor Peshevski, Milorad Jovanovski, Biljana Abolmasov, Jovan Papic, Uroš Đurić, Miloš Marjanović, Ubydul Haque, Natasha Nedelkovska (2019)
    In this paper a heuristic approach for preliminary regional landslide susceptibility assessment using limited amount of data is presented. It is called arbitrary polynomial method and takes into account 5 landslide conditioning parameters: lithology, slope inclination, average annual rainfall, land use and maximum expected seismic intensity. According to the method, in the first stage, a gradation is performed for each of the carefully selected conditioning parameters by assigning so called rating points to the grid cells on which the ...
    klizišta, podložnost
    ... debris and earth slides and rock falls. Over 60% of the occurrences have been defined as intermediate and deep, and those mostly occurred in debris material overlying hard rock masses or in fluvioglacial and proluvial sediments. The depth of some of these landslides varies in the range from 5->25–30 ...
    ... setting, 38% of the landslides in Macedonia have occurred in soil debris which cov- ers schistose or granitic bedrock, 11% in limestone (mostly rock- falls), and 31% in lacustrine sediments. Other units are less well represented. According to the landslide type, in the available re- ports, most of ...
    ... landslides in the Republic of Macedonia showed that bed- rock and superficial geology are among the most important fac- tors for development of landslide processes (PESHEVSKI et al., 2013). This is usually the case with such diverse lithologies as those present in the Western Balkans. In our case study ...

  • Atmospheric exposure vs burying: influences on damage intensity of built-in kersantite in the monument of the Small Staircase (Belgrade, Serbia)

    Nevenka Novaković, Predrag Dabić, Vesna Matović (2023)
    Proučavan je efekat „zatrpanog kamena“ na intenzitet procesa degradacije prisutnih na kersantitu koji je ugrađen u spomenik Malo stepenište. Istraživanja su vršena na uzorcima stene iz kamenoloma i na oštećenim kamenim blokovima ugrađenim u spomenik. Dok su neki delovi stepeništa bili pod zemljom 90 godina, većina kamenih elemenata je bila izložena različitim uslovima sredine i antropogenim uticajima. Urađeno je detaljno mapiranje trenutnog stanja spomenika kako bi se istražio uticaj “zatrpavanja” i kompleksne geometrije spomenika na tip propadanja i variranje ...
    Raspadanje, Indeks oštećenja, Zatrpavanje, Fizička svojstva, Kersantit

  • Split-Desktop software for the analysis of fragment size distribution of blasted rock mass

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović (2023)
    Drobljenje stena je najvažniji pokazatelj u proceni efekata miniranja pri proizvodnom miniranju u površinskoj eksploataciji. Stepen drobljenja stena ima veliki uticaj na efikasnost daljih operacija utovara, transporta, drobljenja i mlevenja. Optimalno drobljenje stena pri proizvodnom miniranju utiče na smanjenje ukupnih troškova proizvodnje. Stoga je pouzdana procena veličine drobljenja odminirane stenske mase veoma važno pitanje, ne samo u operacijama miniranja, već i u rudarskoj proizvodnji. Za predviđanje distribucije veličine komada odminirane stenske mase postoje različiti empirijski modeli. KUZ-RAM model omogućava ...
    Split-Desktop softver, drobljenje stena, miniranje, analiza, digitalna obrada fotografija

  • Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking

    Lazar Kričak, Milanka Negovanović, Nikola Simić, Stefan Milanović (2024)
    Within the Innovation developed several different non-detonating chemical mixtures for non-invasive methods of rock breaking. Laboratory and polygon tests gave the satisfactory results and knowledge enough to start the practical experiments in the field. The basis of this innovation is a theoretical assumption that certain chemical mixtures release a large quantity of gases during combustion. If these gases are found in the enclosed space a growing pressure on the walls of the chamber in which combustion takes place will ...
    non-detonating, chemical mixture, rock breaking, borehole pressure

  • Models of Determining the Parameters of Rock Mass Oscillation Equation with Experimental and Mass Blastings

    Suzana Lutovac, Branko Gluščević, Rade Tokalić, Jelena Majstorović, Čedomir Beljić (2018)
    ... is used for rock destruction, and part of energy, in the form of seismic wave, is lost in the rock mass causing rock mass oscillation. Investigations of the character and behavior of the pattern of seismic wave indicate that the intensity and nature of the seismic wave are influenced by rock mass properties ...
    ... open pit, located in central Serbia. In this paper, parameters n and K from Sadovskii’s equation were determined in three ways—models in the given work environment. It was noted that, in practice, all three models can be successfully used to calculate the oscillation velocity of the rock masses. Keywords: ...
    ... explosive and given in the following form R = r r0 . Thus, we have obtained the oscillation law of rock mass, i.e., the equation of Sadovskii. 3.2. The Property of the Rock Mass Oscillation Equation The rock mass oscillation equation, given in the Equation (1) may be written in the form: v(R) = K·R−n ...

  • Uniaxial compressive strength test before and after standard fire test on rock mass

    Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović (2022)
    ... high temperatures in case of fire, as they were in standard fire test. REFERENCES Hoek, E. and Brown, E.T., 1980. Underground excavations in rock. The Institution of Mining and Metallurgy, London. Wittke, W., 2014, Rock Mechanics Based on an Anisotropic Jointed Rock Model (AJRM) SRPS ...
    ... the structure of the rock mass, grain size and orientation, number and arrangement of cracks and fissures. For the same rock, strength may be different, depending on physical characteristics. Heat of environment can affect structure of rock mass, which results in a change in uniaxial compressive ...
    ... strength of rock after fire. Uniaxial compressive strength is an important parameter of rock material in the field of rock mechanics. It is the basic parameter for determining strength and classification of rock mass. It is determined experimentally, by laboratory strength testing. ...

  • Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Nikola Simić, Jelena Majstorović (2024)
    During construction of buildings in urban areas, sometimes there is a need to blast solid rock mass in the immediate vicinity of the surrounding buildings. In that case, the aim is not only to increase the efficiency of blasting, but also to reduce harmful effects of ground vibration induced by blasting. At the same time, it is very important to protect the buildings located in the safe zone from the blast site as well as remaining rock mass around ...
    expansive mortar, artificial screens, pressure, rock breaking, building foundation

  • Rock slope stability analysis under Hoek–Brown failure criterion with different flow rules

    Svetlana Melentijević, Zoran Berisavljević, Dušan Berisavljević, Claudio Olalla Marañón (2024)
    The stability analysis of homogeneous rock slope following the Hoek–Brown failure criterion under the hypothesis of different flow rules is performed based on limit equilibrium and finite element methods. The applied failure criterion is the generalized Hoek–Brown that can be introduced as a shear/normal function in analysis applying different flow rules. The results are compared with those obtained by the application of equivalent shear strength parameters of the Mohr–Coulomb criterion, considering that this is still the most widely used ...
    Kružna klizna površ, Huk-Braunov kriterijum loma, Kriterijum popuštanja, Smičuća/normalna funkcija, Nivo napona, Verovatnoća i parametarska analiza

  • Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation

    Maja Franković, Nevenka Novaković, Vesna Matović (2015)
    The Dark Gate is the monument of culture, part of the cultural and historical complex of the Belgrade Fortress. It is constructed of limestone blocks that after 270 years of exposure to environmental conditions and different anthropogenic influences show wide ranges of decay forms. During 2007, detail registration of all built limestone microfacies and weathering forms was done using tools of monument mapping. A correlation scheme ‘‘intensity– damage category’’ was made according to the type, intensity, and distribution of ...
    Krečnjak, mapiranje, Indeks raspadanja, brzina raspadanja, progresija
    ... algal rudstone and grainstone in almost same prevalence. Their distribution in this portal imply an organized building technique. While the soft and easy workable algal rudstone was used for upper part and arch of the portal, hard and compact grainstone was built in lower parts of facade. Content ...
    ... weathering forms. Mapping models used in the study included rock type mapping and weathering form mapping. Determination of damage categories on built stone blocks made it possible to calculate damage indices. Field observation of the Dark Gate was done in November-December 2007. For lithological ...
    ... homogeneous distributed through- out the rock (Fig. 2f). Size of these clasts reaches up to 1 cm. Among the sparry varieties of this microfacies, in- trasparrudite, biosparrudite to intrabiosparrudite may be distinguished. They are made of simple and complex in- traclasts and fossil fragments of ...

  • Flyrock induced by blasting in surface mining

    Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac (2022)
    Miniranje predstavlja i dalje najefikasniji i najjeftiniji način eksploatacije velikih količina čvrstih mineralnih sirovina na površinskim kopovima. Energija eksplozije se koristi za fragmentaciju čvrste stenske mase do zahtevane granulacije. Pored pozitivnih efekata miniranja, postoje i određeni neželjeni efekti svakog procesa miniranja koji se mogu javiti, a to su: potresi tla, razletanje komada stene, vazdušni udari, otrovni i zagušljivi gasovi i prašina. Razletanje komada stene je nekontrolisano izbacivanje fragmenata odminirane stenske mase i predstavlja jedan od glavnih izvora materijalne štete ...
    razletanje, bušenje, miniranje, površinska eksploatacija, bezbednost, nesreća

  • Composition of organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in East Herzegovina (External Dinarides, Bosnia and Herzegovina)

    Nikoleta Aleksić, Aleksandar Kostić, Miloš Radonjić (2021)
    This paper presents the first data on the organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in the East Herzegovina region of the External Dinarides. Representative, organic-rich samples from outcropping sedimentary rocks of different ages in the area (Triassic to Neogene) were selected and analysed. The organic matter was studied by Rock-Eval pyrolysis and under the microscope in reflected non-polarized light and incident blue light. The results obtained show the presence of different types of organic ...
    nafta i gas, Rock-Eval, refleksija vitrinita, maceral, termička zrelost
    ... (Vlahovi¢ et al., 2005) and reflect- ed in a variety of deposited rock types that can be observed in East Herzegovina (Fig. 1C). 4 N. ALEKSIĆ Et Al. �e oldest stratigraphic unit in the area is the mixed si- liciclastic-carbonate succession of the Late Triassic, exposed in the core of the Lastva Anticline ...
    ... fraction (< 2 mm) was used for preparing petrographic “whole rock” specimens (polished block), and the pulverized rock (0.10–0.25 mm) was used for Rock-Eval pyrolysis. Methods In this study, common analytical methods were used: Rock-Eval pyrolysis and organic petrographic investiga- tions, including ...
    ... crushed fraction (< 2 mm) was used for preparing petrographic “whole rock” specimens (polished block), and the pulverized rock (0.10-0.25 mm) was used for Rock-Eval pyrolysis. Methods In this study, common analytical methods were used: Rock-Eval pyrolysis and organic petrographic investiga- tions, including ...

  • Uticaj raspadanja na stabilnost kosina u mekoj stenskoj masi

    Anđela Despotov (2024)
    U radu je opisano ponašanje mekih stenskih masa koje su izložene porecesu raspadanja tokom određenog vremenskog perioda. Meke stenske predstavljaju kritične vrste stenskih masa pošto izazivaju različite probleme tokom izvođenja građevinskih radova. Meke stene mogu biti sedimentne stene, raspadnute metamorfne i magmatske stene. Odlikuju se niskim vrednostima čvrstoće, visokom deformabilnošću, visokom plastičnošću, podložne su dezintegraciji i fizičko-hemijskom raspadanju, odnosno ubrzanom dejstvu površinskog raspadanja usled atmosferskih uticaja.Za klasifikaciju mekih stenskih masa koriste se modifikovane verzije već postojećih klasifikacionih sistema. Jedan ...
    meke stenske mase, dezintegracija, klasifikacioni sistemi, Slake durability test
    ... tectonicallydisturbed heterogeneous rock masses, such as flysch. Bulletin of Engineering Geology and the Environment 78 24. Patton FD (1966), Multiple modes of shear failure in rock. In: Proceedings of the 1st ISRM Congress, International society for rock mechanics, Lisbon, Portugal, September-October ...
    ... Journal, 2, 4-16 17. Hoek, E., Brown, E.T., (1997) Practical Estimates of Rock Mass Strength, International Journal Rock Mechanics Mining Science, 34, 1165-1186. 18. Hoek E., Brown E.T., (1980) Underground Excavations in Rock. London: Institution of Mining and Metallurgy 527 p, London 19. ISO ...
    ... Approach. Proceedings of the 2nd International Symposium on the Geotechnics of Hard Soils / Soft Rocks. Vol. 1, Naples, Italy 10. Vlastelica, G., Miščević, P., Pavić, N., (2016) Testing the shear strength of soft rock at different stages of laboratory simulated weathering. Građevinar, Vol. 68 No ...

  • The shear strength evaluation of rough and infilled joints and its indications for stability of rock cutting in schist rock mass

    Dušan Berisavljević, Zoran Berisavljević, Svetlana Melentijević (2022)
    Construction of E75 highway section through Grdelica gorge was one of the most demanding projects realized in recent Serbian history. The alignment approximately 25 km long consists of several tens of bridges, two tunnels, three galleries and cuts with total length of 6 km. The alignment passes through highly anisotropic Palaeozoic schist rock formation of different weathering grades. This study focuses on shear strength properties of discontinuities, which are found to be the critical feature contributing to the occurrence ...
    Diskontinuitet, nelinearni kriterijum loma, anizotropija, hiperbolična anvelopa

  • Развој модела конструкције просторија отварања рудника са подземном експлоатацијом

    Dražana M. Tošić (2016-08-26)
    Приликом израде подземних просторија у стјенској маси долази до нарушавања природне равнотеже напонских стања стијенског масива који су владали прије израде тих просторија, при чему долази до појаве прертасподјеле напона и његове концентрације у појединим правцима и тачкама, односно долази до појаве пластичних деформација које су праћене ломљењем стијенске масе и кретањима материјала према откопаном простору...
    модел, метод коначних елемената, просторија отварања, напон, дефеормација стијенског масива, алгоритам функционалних зависности
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  • Parameter determination of soil oscillation law using quotient of the relative growth increments of oscillation velocity and reduced distances at “Nepričava“ open pit mine

    Suzana Lutovac, Sanja Bajić, Marina Ravilić, Radmila Gaćina (2015)
    ... energy, in the vicinity of blasting location, destructs and crushes rock mass, a bit further creates cracks and permanent deformations in the rock mass, and even further it is being transformed into elastic deformations. The effect of elastic seismic wave is movement of particles of the rock mass from ...
    ... monitoring point m, Q - amount of explosive kg. 2.1. Derivation of equation of rock mass oscillation law If, by blasting in the specific environment, the relative increase in the oscillation velocity of the rock mass and the relative increase of the reduced distance are monitored, then it can ...
    ...         (11) By the replacement of the value for the parameter n in the equation (11), found in this way, we obtain the relation for the oscillation velocity of rock mass in the monitored environment: 1 1 n R v v R        Thus, to determine the ...

  • Blasting mats for the protection of people, structures and the environment in proximity to the blast site

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović (2023)
    Енергија експлозије која се ослобађа током процеса детонације минских пуњења у бушотинама користи се за дробљење чврсте стенске масе на комаде различитих облика и величина, у зависности од карактеристика стене и оптимизације параметара бушења и минирања. Поред позитивних ефеката минирања, постоје и одређени нежељени ефекти сваког процеса минирања који се могу јавити, а то су: потреси тла, разлетање комада одминираног материјала, ваздушни удари, загушљиви и отровни гасови и прашина. Разлетање комада је неконтролисано избацивање комада одминиране стенске масе и ...
    mecevi za miniranje, pokrivanje, razletanje komada, miniranje