Претрага

Упит dcterms_subject_txt:field stress

126 items

  • Influence of DEM resolution on numerical modelling of debris flows in RAMMS - Selanac case study

    Jelka Krušić, Biljana Abolmasov, Mileva Samardžić Petrović (2019)
    Debris flows induced by intensive rainfall represent very hazardous phenomena in many parts of the World. Methods for prediction of runout distance of flow like mass movements are different and depending on the input data, rheology, and available or appropriate numerical solution. However, sometimes it is not easy to obtain pre event and post event high-resolution data in the rural or mountainous area. Thus, the topology of terrain is the most important input parameter for the every real case ...
    tecišta, modeliranje, RAMMS, DEM
    ... basal shear stress in each grid cell: 𝑒𝑚 = 0 𝑓𝑜𝑟 𝜏 < 𝜏𝑐 (5) 𝑒𝑚 = 𝑑𝑧𝑑𝜏 (𝜏 − 𝜏𝑐) 𝑓𝑜𝑟 𝜏 ≥ 𝜏𝑐 (6) The potential erosion depth (per kPa) dz/dt controls the rate of vertical erosion (in the z-direction) as a linear function of channel-bed shear stress. Even ...
    ... in snow avalanche models, which means that is basically one-phase. It is assumed that the initiation mass starts to move as a plug defining shear stress in different points of transportation path. RAMMS DBF software is FVM (Finite Volume Method) based software for modelling of debris flows. RAMMS ...
    ... the Voellmy friction relation (Salm et al., 1990; Salm, 1993) and specifies the dry-Coulomb term (friction coefficient / scaling with the normal stress and the viscous or turbulent friction (coefficient/ depending on the flow velocity U (Christen et al.,2010a, 2012; Bartelt et al., 2013): 𝑆𝑓 ...

  • Determining seismic hazard in slowly deforming region: Can we gather enough information from karst caves?

    Ана Младеновић, Јелена Ћалић (2021)
    ... research area is characterized by strike-slip tectonics, most likelyresulting from far-field stress generated by the collision of the Adriatic microplate, the Moesianindenter and the tectonic units in-between. Such stress field is shown to be highly heterogeneouseven in this relatively small research area, ...
    ... led to intensive karst process and formation of both surface and underground karst forms.Therefore, investigations of faults and deformations on the field surface are very difficult, butinvestigations of neotectonically active faults inside the karst caves can give a lot moreinformation. In this abstract ...

  • Numerical modeling of Selanac debris flow propagation using SPH code

    Jelka Krušić, Biljana Abolmasov, Miloš Marjanović, Manuel Pastor, Saeid M. Tayyebi (2021)
    The Selanac debris flow is a very huge event triggered after extreme rainfall caused by Cyclone Tamara activity in the Republic of Serbia in May 2014. The Selanac case study was already modelling in different programs using Voellmy rheology assumptions like RAMMS software. In this paper research are focusing particularly on the process of debris flowing from initiation zone to main deposition area using Geoflow SPH two-phase model considering frictional rheology law. Main rheological parameters are back-calculated using also ...
    debris flow, modelling, SPH code, DEM
    ... C. a kinetic relation between the deformation-rate tensor and velocity field, and SCG-XIII INTERNATIONAL SYMPOSIUM ON LANDSLIDES. CARTAGENA, COLOMBIA- JUNE 15th-19th-2020 D. rheological equation relating the soil-stress tensor to the deformation-rate tensor. Generally, it consists of the ...
    ... voids filled with either water or mud. If the shear resistance of the fluid phase can be neglected, the stress tensor in the mixture can be decomposed into a ‘pore pressure’ and an effective stress, and the mechanical behavior of the mixture can be described by a system of differential equations governing ...
    ... soil and basal surface is smaller than the friction angle of the fluidized soil, the basal shear stress is given by: , (2) - where are: b basal shear stress, depth averaged velocity, and ’d is submerged density given by ...

  • Investigation of nanostructured Ca0.9Er0.1MnO3 obtained by sucrose nitrate procedure

    Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)
    ... Serbia This paper presents the influence of geometry on the determination of the stress intensity factor KI on specimens produced by the selective laser sintering technique.The analysis of the determination of the stress intensity factor includes experimental and numerical tests. For this purpose ...

  • Overview of the hydrogeological investigations of recently discovered world class deposits in Serbia

    Nebojša Atanacković, Vladimir Živanović, Veselin Dragišić, Sava Magazinović (2019)
    Europe industry has growing concerns on availability of the raw materials. To address this challenge, the European Commission has created a list of critical raw materials for the EU, launched EIT Raw Materials initiative, and continuously support research projects (like INTRAW, UNEXMIN etc.) with the aim of reducing the dependency and meeting growing demands. In the last 15 years Serbia is experiencing new bust in geological exploration of mineral deposits. Currently 167 exploration licenses are active, covering approximately 6000 ...
    Groundwater, Raw materials, Lithium, Mining, Field hydrogeology

  • Еволуција напонског поља подручја Интерних Динарида у Србији током алпске орогенезе

    Ana S. Mladenović (2015-06-19)
    Циљ ове докторске дисертације био је реконструкција еволуције напонског пољаЗемљине коре у подручју Интерних Динарида у Србији током Алпске орогенезе.Истраживања за потребе решавања овог проблема су изведена у два дела. Првидео обухватао је анализу палеонапона на дефинисаном подручју истраживања,док се други део односио на анализу тренутно активног поља напона у овом делуБалканског полуострва. Истраживано подручје обухвата унутрашњи деоДинарског орогеног појаса, који се простире у централној и западној Србији. Собзиром на циљ истраживања, истраживано подручје је дефинисано тако даобухвата три ...
    Интерни Динариди, анализа палеонапона, фокални механизмиземљотреса, напонско поље, тектоно-магматски догађаји
    ... calculate the stress tensors which activated the considered faults. Relative and stratigraphic age of these stress tensors and reconstructed tectonic phases, was determined based on the age of faults used to calculate the specific stress tensor. The analysis of the recently active stress field in the ...
    ... 552.3:534.64:624.07/.1 (497.11-15)(043.3) STRESS FIELD EVOLUTION IN THE AREA OF THE INTERNAL DINARIDES IN SERBIA DURING THE ALPINE OROGENIC CYCLE Abstract The main aim of this PhD thesis was to reconstruct the evolution of the stress field of the Earth's crust in the area of Internal ...
    ... the Kopaonik Mts. Keywords: Internal Dinarides, paleostress analysis, earthquake focal mechanisms, stress field, tectono-magmatic events Scientific field: Geosciences Field of academic expertise: Dynamic geology UDK number: 55:551.24.03:551.1/.761 552.3:534.64:624.07/.1 ...

  • 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
    ... ranged from 5–10 min, with a stress rate of 0.1–0.3 kN/s. The specimens were tested at room temperature of 20 ± 2 ◦C, and the time between field extraction of samples and the laboratory testing was no longer than 15 days. The values of horizontal σ3 and vertical σ1 stress were obtained based on the ...
    ... 10. Relationship between maximum and minimum stress for different participation of AD. Minerals 2021, 11, 813 12 of 19 Also, the analysis included relationships between shear and normal stresses that were constructed based on the Mohr circles of stress. This analysis determined the envelopes for all ...
    ... connect separate discs [4] was shown as inadequate due to plaster failure at lower loads, causing the discs to displace and introducing non-uniform stress distribution throughout the disc interfaces. Tziallas et al. [1] found that the use of plaster to connect separate discs is unnecessary, considering ...

  • Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate

    Marija Ilić, Franz-Hubert Haegel, Vesna Pavelkić, Snežana Zlatanović, Zoran Marković, Aleksandar Cvjetić (2015)
    Microemulsion systems with water, toluene and nonionic surfactants are interesting for application due to the excellent solvent properties of aromatic hydrocarbons. In this study, the pseudo-binary phase diagram (“fish-diagram”) of such a ternary system was investigated using a branched technical alkyl polyethoxylate. Lutensol ON 50 (i-C10E5) was considered a suitable surfactant. The system with technical branched i-C10E5 exhibits very long, and for compositions near optimum solubilization, i.e., the minimum content of surfactant needed for a bicontinuous microemulsion, extremely long ...
    микроемулзија, толуен, оксоалкохол етоксилат, термодинамичка стабилност, тернарни фазни дијаграми, дијаграми „fish“

  • Geotechnical Conditions for Construction of Savski Trg Metro Station as a Part of the Belgrade Metro Line One

    Nemanja Stanic, Dragoslav Rakic, Josip Isek, Slavoljub Simic (2024)
    In order to solve serious traffic congestion in Belgrade, a number of studies regarding the Belgrade Metro construction have been carried out since 1973. However, only in 2019, the routes of the future metro lines 1 and 2 were de-fined as a part of the General Metro Construction Project. The lines are de-signed to intersect at the location of Sava Square, where an interchange met-ro station will be built. It represents a complex geotechnical structure consist-ing of three different ...
    metro station, geotechnical modelling, displacements

  • Structural and geochronological constraints from the Drina-Ivanjica thrust sheet (Western Serbia): implications for the Cretaceous–Paleogene tectonics of the Internal Dinarides

    Kristof Porkoláb, Szilvia Kövér, Zsolt Benkó, Gabor Héja, Melinda Fialowski, Balázs Soós, Nataša Gerzina Spajić, Nevenka Đerić, László Fodor (2019)
    Internal Dinarides, Drina-Ivanjica thrust sheet, Deformation history, K–Ar dating, Obduction, Structural analysis
    ... The vergence of folding and thrusting is top-NNE along the section Tectonic evolution of the Drina-Ivanjica thrust sheet 007 simplified stress field Stereoplot Legend Map Legend projection of Certainty of fault kinematics i *ca\jqulaped S1 axis ORR Miocene dis D oaoied d2as - 7 probable ...
    ... |0 56 Pc 66 D2 K / 145——- k D1 J [] L] | — L] normal fault l IJAr aqes of /O/ present study strike-slip fault % Inferred stress field SA – strike-slip I : ( l Stratigraphic range of Albian-Cenomanian sediments reverse fault - Cretaceous sediments - Western Vardar ...
    ... Summary of the Jurassic-Neogene deformation history of the study area. Stereoplots of the simplified deformation patterns show the approximate stress field and related structures through time. cannot correlate it with the innermost thrust sheets of the Internal Dinarides (Jadar-Kopaonik thrust sheet) ...

  • Cutting Resistance Laboratory Testing Methodology for Underwater Coal Mining

    Vladimir Čebašek, Veljko Rupar, Stevan Đenadić, Filip Miletić (2021)
    Geology,Geotechnical Engineering and Engineering Geology
    ... Maximum axial stress, σ1, for each value of confining pressure, σ3 (σ3 = 400, 800, 1600 kPa) (Table 3), was used to approximate the cutting resistance per unit area of the slice, KA (kPa), according to the diagram shown in Figure 6. The values of cutting resistance, KA (kPa), based on axial stress, σ1, for ...
    ... σ σ σ σ σ σ σ σFigure 19. Relationship between cutting resistance, KA, and vertical stress, σ1. σ σ σ σ σ σ σ σ σ σ σ σ σ σ σ Figure 20. Relationship between cutting resistance, KA, and confining stress, σ3 (σ3 = 400, 800, 1600 kPa) (1—lowest value of KA, 2—highest value of KA, 3—empirical ...
    ... in Figures 19 and 20. Table 3. Results of cutting resistance tests for all defined confining pressures, σ3. Confining Pressure, σ3 (kPa) Vertical Stress, σ1 (kPa) Cutting Resistance, KA (kPa) Lowest Value Highest Value KA = σ1/10 0 10,820 903.81 1431.77 1082 400 12,090 952.89 1519.76 1209 800 13,440 ...

  • Fault type assessment based on vertical gravity gradient anomalies – advantages and limitations

    Ivana Vasiljević, Snežana Ignjatović, Branislav Sretković (2024)
    The type of dip-slip faults can be assessed based on the analysis of vertical gravity gradients. Theoretically, just a simple comparation of the gradient extreme values can give us an answer whether the fault is normal or reverse (thrust). Practical application of this method is far more complicated and the results depend on a number of parameters, such as a complexity of geological setting, the quality of gravity data, dip angle and displacement of the fault, density contrast, etc. ...
    dip-slip faults, vertical gravity gradients, field data analysis
    ... for fault type determination are presented in the paper through the application on synthetic models and field example. INTRUDUCTION The gravity method is based on the analysis of gravity field variations produced by the subsurface density distribution. Gravimetry is often applied in the mapping ...
    ... the Republic of North Macedonia application of the method can be much more challenging. FIELD EXAMPLE A profile across the South Morava trench, near Brestovac in eastern Serbia, was chosen as a field example (Fig. 3). First, the gravity anomalies werc calculated for the wider area around the ...
    ... the same. [] ? 4 6 8 10 12 14 South Morava x [km] Fla FIb F2a F2b River F3 F4 i i vi < VOA - K i (b) s VOA V X V a \ c u Figure 3. Field example from South Morava trench: (a) vertical gravity gradient (Uzz) curves A, B and C and (b) disposition of the faults obtained from geological ...

  • 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
    ... by the rock stress surrounding the gate road. Deformation dynamics is the study of time varying response of support under dy- namic loads. These loads are primarily considered a change of rock stress intensity induced by mining activities. As a stope approaches the gate road, the rock stress intensity ...
    ... 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 ...
    ... methods are characterized by a long production cycle, and if we add disruptions then it is obvious that the 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 ...

  • The final closure of the Vardar Ocean: paleomagnetic, AMS and structural results

    Emö Márton, Marinko Toljić, Vesna Lesić, Vesna Cvetkov (2020)
    ... zone will be discussed in the context of the post-Oligocene CW rotation of the flanking areas and the general NE-SW orientation of thecompressional stress field outside of the zone. Acknowledgement. This work was financially supported by the National Development andInnovation Office of Hungary, project K ...

  • Geotechnical conditions of “Debelo brdo” tunnel construction on the highway E-80: Nis-Merdare-Pristina (“Peace Highway”)

    Dragoslav Rakić, Irena Basarić Ikodinović, Radojica Lapčević, Dragan Lukić (2024)
    The construction of the highway E-80 has begun in Serbia, which will represent the traffic hub of the Western Balkans and will be part of the main regional transport network of Southeast Europe. Its total length through Serbia is 77 km, and one part of the route is designed through a typical plain terrain, while a larger part of the route passes through hilly terrain. The construction of the tunnel “Debelo brdo” is planned partly in an open cut ...
    „Debelo brdo“ tunnel, temporary slopes, open cut excavation, tunnel excavation, piles

  • Insights into dike nucleation and eruption dynamics from high-resolution seismic imaging of magmatic system at the East Pacific Rise

    Milena Marjanović, Suzanne M. Carbotte, Alexandre Stopin, Satish C. Singh, René-Édouard Plessix, Miloš Marjanović, Mladen R. Nedimović, Juan Pablo Canales, Hélène D. Carton, John C. Mutter, Javier Escartín (2023)
    Multidisciplinary

  • Uporedna analiza stabilnosti završnih kosina površinskog kopa „Veliki Krivelj“

    Mihajlo Topalović (2023)
    Površinski kop „Veliki Krivelj“ nalazi se u blizina grada Bora i u neposrednoj blizini sela Krivelj. Od 2018. godine je u vlasništvu kineske kompanije „Zijin“ koja ima udeo od 63% vlasništva celokupnog RTB-a Bor. Na površinskom kopu obavlja se masovna eksploatacija rude bakra opremom visokog kapaciteta. Za bušenje se koriste bušilice prečnika od 250 do 310 mm, a za utovar minirane rude i jalovine bageri čija je zapremina kašike 15 m3 i 22 m3. Za površinski kop „Veliki Krivelj“ ...
    stabilnost kosina, metoda konačnih elemenata, površinski kop, Veliki Krivelj, završna kosina

  • GNSS Time Series as a Tool for Seismic Activity Analysis Related to Infrastructure Utilities

    Sanja Tucikešić, Ankica Milinković, Branko Božić, Ivana Vasiljević, Mladen Slijepčević (2021)
    GNSS, Time series, Seismic deformations, Earthquake, Infrastructure utilities

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... CounterWeight Positon,0.63444. m - | |_Pump Intake Pressure D F·:tnr} 176092 ___| Method Stress (Max) 659.216 |bar | Calculated From IPR. Stress (Min) 290.254 – |bar Calculated From Fluid Level Stress (Max Alowable) 2145.51 - |bar Torsional Effectiveness (ITE), 13.6466 percent Intake Pressure ...
    ... operational life of sucker rods depends on the quality of the material as well as the working conditions, including: maximum stress, the range of maximum and minimum stress, and the number of strokes per minute. All these factors affect material fatigue and the potential for rod failure,. In some ...
    ... fluid through in which they move. – Internal Friction: Within the material of the rod strings and tubing, which occurs due to deformation under stress [3,4]. Walking Beam Equalizer Bearing Horsehead — Horsel Equalizer Pitman Crank Gear Reducer Wireline Hanger (Bridle) Counterweight ...

  • A comparative study of the molecular and isotopic composition of biomarkers in immature oil shale (Aleksinac deposit, Serbia) and its liquid pyrolysis products (open and closed systems)

    Gordana Gajica, Aleksandra Šajnović, Ksenija Stojanović, Jan Schwarzbauer, Aleksandar Kostić, Branimir Jovančićević (2021)
    The molecular and isotopic composition of biomarkers in initial bitumen isolated from immature (0.41% Rr) oil shale samples (Aleksinac deposit) and liquid products obtained by pyrolysis in open (OS) and closed (CS) systems are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in liquid products is determined. The applicability of pyrolysis type, numerous biomarkers and carbon isotopic compositions (δ13C) of n-alkanes in liquid pyrolysates is established. Pyrolysis experiments were ...
    Uljni šejl, Aleksinac, organska supstanca, otvoreni i zatvoreni sistem pirolize, biomarkeri, izotopski sastav ugljjenika