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Safety analysis of the Żelazny Most tailings pond: qualitative evaluation of the preventive measures effectiveness

Łydżba Dariusz, Różański Adrian, Sobótka Maciej, Pachnicz Michał, Grosel Szczepan, Tankiewicz Matylda, Stefanek Paweł

Studia Geotechnica et Mechanica

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2021

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Vol. 43, nr 2

181--194

EN

In this paper, a qualitative safety analysis of the Żelazny Most tailings pond is addressed. This object is one of the largest facilities of this type in the world being a crucial element in the technological line of copper production in KGHM Polska Miedź S.A. The assessment of the effectiveness of two types of preventive measures, i.e., relief wells and loading berms, is investigated based on displacement and stability analysis of two 2D cross-sections in a technical section of the dam. The study shows that the considered preventive measures generally have a positive impact on increasing the safety level of the structure during its further raise. In particular, their effectiveness is most evident when they are applied simultaneously. It is eventually suggested that the selection of final solutions to be applied on the facility should be based on the quantitative 3D analysis.

2

A comprehensive approach to the optimization of design solutions for dry anti-flood reservoir dams

Łydżba Dariusz, Różański Adrian, Sobótka Maciej, Pachnicz Michał, Grosel Szczepan, Rainer Jakub

Studia Geotechnica et Mechanica

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2021

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Vol. 43, nr 3

270--284

EN

The article proposes the methodology of designing dams of dry flood control reservoirs. The algorithm is developed so as to meet all the requirements given in the Eurocode 7 and, at the same time, to be efficient in terms of necessary calculation time. Furthermore, the presented numerical procedure enables the optimization of design solutions, e.g. the depth and length of the anti-filtration barrier, by means of parametric analyses. The approach assumes the use of numerical methods, in particular, finite element (FE) analysis. Three-dimensional (3D) reconstruction of the terrain topography and subsoil layer arrangement performed in step (1) sets the base for further analyses. In step (2), the filtration phenomena are assessed based on the 3D analysis of a transient groundwater flow. In step (3), the state of displacement is evaluated and the stability is verified for all the relevant phases of construction and operation of the facility, in particular, in the course of simulated flood detention. The analyses in step (3) are carried out on 2D models corresponding to the design cross-sections of the dam. This significantly reduces the computation time (compared to 3D analysis) and, at the same time, provides a safe estimate of factor of safety. The performance of the proposed algorithm is shown on the numerical examples of the computations concerning the dam of Szalejów Górny dry anti-flood reservoir located in Poland.

3

Tunele kolejowe. Rewitalizacja, ocena stanu technicznego, projekt naprawczy, modelowanie numeryczne : problemy naukowo-techniczne

Łydżba Dariusz, Dróżdż Arkadiusz, Wątroba Paweł, Różański Adrian, Sobótka Maciej, Pachnicz Michał, Grosel Szczepan, Rainer Jakub

Geoinżynieria : drogi, mosty, tunele

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2021

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nr 2

92--102

4

Identification of changes in mechanical properties of sandstone subjected to high temperature: meso-and micro-scale testing and analysis

Różański Adrian, Różańska Anna, Sobótka Maciej, Pachnicz Michał, Bukowska Mirosława

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 1

461--482

EN

Material properties largely depend on their structure, and are strongly dependent on the scale of observation. Under the influence of various processes, the structure of a material can undergo evolution, which leads to major changes in the mechanical parameters and morphology of the medium. To understand the behaviour of a given material exposed to the influence of various factors, e.g. loading and temperature treatment, and to be able to modify it appropriately, it is crucial to recognize its structure both in the scale of engineering applications and at the micro-scale. The article proposes a procedure for assessing changes in the structure of sandstone exposed to the temperature treatment. The presented procedure allows the morphology of the material to be evaluated and the influence of temperature treatment on mechanical parameters of rocks to be analysed, by combining use of different laboratory techniques. The changes in rock material have been characterized using three investigative techniques, i.e. a uniaxial compression test, nanoindentation and micro-computed tomography. The uniaxial compression tests were carried out for 11 different temperature values in the range of 23–1000 °C, which enabled the determination of the change in uniaxial compressive strength and Young’s modulus of the sandstone as a function of temperature. Micro-scale laboratory tests were utilised to identify changes in the mechanical and morphological parameters of the sandstone exposed to the temperature of 1000 °C. The results were referred to those obtained for the reference samples, i.e. not subjected to heating (T = 23 °C). Comparison of the results showed an evident relation between the microstructure changes and the mesoscopic properties.

5

Ocena stateczności zapory ziemnej suchego zbiornika przeciwpowodziowego Roztoki Bystrzyckie w trakcie przejścia fali powodziowej

Batog Andrzej, Pachnicz Michał, Różański Adrian, Sobótka Maciej, Stefaniuk Damian, Chudy Grzegorz, Wróblewski Tomasz

Gospodarka Wodna

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2019

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Nr 1

18--23

PL

Specyfika pracy zapory suchego zbiornika przeciwpowodziowego wymusza konieczność sprawdzania stateczności zarówno wtedy, gdy zbiornik jest suchy, jak i gdy jest poddany działaniu przechodzącej fali powodziowej. Aby uwzględnić efekty przejścia fali powodziowej, należy najpierw dokonać analizy nieustalonego przepływu filtracyjnego, a następnie sprawdzić stateczność dla wybranych chwil czasowych. Taką procedurę zastosowano do oceny stateczności zapory ziemnej suchego zbiornika przeciwpowodziowego Roztoki Bystrzyckie. Analizy przeprowadzono w ujęciu metody elementów skończonych, w programie ZSoil.

EN

The specificity of a dry flood control reservoir functioning requires stability verifications both when the reservoir is dry and during high water stages. In order to take into account the consequences of the flood wave, we need first to carry out an analysis of the transient filtration flow and then check the stability for selected moments. Such procedure was applied for the stability analysis of the Roztoki Bystrzyckie dry flood-control reservoir embankment. The analysis was carried out using the finite elements method, in the ZSoil software.