INTEGRATING OF GEORADAR ANS SEISMIC STUDIES OF THE TAILINGS DAM

Mapping Intimacies ◽

10.32008/geolinks2021/b1/v3/49 ◽

2021 ◽

Author(s):

Alexander Dyakov ◽

A. Kalashnik

Keyword(s):

Internal Structure ◽

Water Saturation ◽

The Body ◽

Tailings Dam ◽

Hydraulic Facility ◽

Tailings Dams ◽

Geophysical Surveys ◽

In Situ Experiments ◽

Water Saturated

Identification of water-saturated zones in the tailings dams is an actual scientific and practical task in terms of providing, first of all, their mechanical strength and filtration stability. The prevention of accidents in tailings is complicated by the circumstance that the processes of increased filtration, appearing and developing in the dam body, are not fixed on the initial stages by visual and traditional methods. Insufficiency, from the point of view of data completeness, of networks of piezometric boreholes on tailings dams does not allow solving the tasks of necessary information hydrological support. At the same time, the use of active- sounding geophysical study methods allows obtaining sufficiently detailed information about the peculiarities of the internal structure of the tailings dam and the degree of water saturation of the composing soils. A reasoned choice of geophysical methods, as well as their combination, allows increasing the level and reliability of obtained data at subsurface studies. The paper presents the results of in-situ experiments on the study of the tailings dam of the mining enterprise by different in nature wave GPR (georadar) and seismic methods. A comparative analysis of the conducted studies has allowed clarifying the internal structure and assessing the dam’s condition, paying special attention to the identification of local zones of increased water saturation and filtration. Based on the calculated correlation coefficient of electromagnetic and seismic wave velocity values, it was revealed that synchronization of geophysical surveys allows significantly increasing the reliability of in-situ determinations, as well as obtaining more reliable data. The results of the studies are the basis for predicting the most vulnerable places (zones) of a bulk ground hydraulic facility, as well as the localization of water-saturated areas in the body of the ground structures with greater reliability and performance.

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Combination of ground penetrating radar and seismic surveys of the tailings dam

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/938/1/012020 ◽

2021 ◽

Vol 938 (1) ◽

pp. 012020

Author(s):

A Kalashnik ◽

A Dyakov

Keyword(s):

Internal Structure ◽

Ground Penetrating Radar ◽

Water Saturation ◽

The Body ◽

Tailings Dam ◽

Geophysical Surveys ◽

In Situ Experiments ◽

Water Saturated ◽

Ground Penetrating

Abstract Identification of water-saturated zones in the tailings dams is an actual scientific and practical task in terms of providing, first of all, their mechanical strength and filtration stability. Use of active sounding geophysical study methods allows obtaining sufficiently detailed information about the peculiarities of the internal structure of the tailings dam and the degree of water saturation of the composing soils. The paper presents the results of in-situ experiments on the study of the tailings dam of the mining enterprise by ground penetrating radar (GPR) and seismic methods. A comparative analysis of the conducted studies has allowed clarifying the internal structure and assessing the dam’s condition, paying special attention to the identification of local zones of increased water saturation and filtration. Based on the calculated correlation coefficient of electromagnetic and seismic wave velocity values, it was revealed that synchronization of geophysical surveys allows significantly increasing the reliability of in-situ determinations, as well as obtaining more reliable data. The results of the studies are the basis for predicting the most vulnerable places (zones) of a bulk ground hydraulic facility, as well as the localization of water-saturated areas in the body of the ground structures with greater reliability and performance.

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Experimental Study About Water Saturation Influence on Changes in Reservoirs Petrophysical Properties

Walailak Journal of Science and Technology (WJST) ◽

10.48048/wjst.2021.20594 ◽

2021 ◽

Vol 18 (13) ◽

Author(s):

Sudad Hameed AL-OBAIDI ◽

Victoria SMIRNOV ◽

Hiba Hussein ALWAN

Keyword(s):

Physical Properties ◽

Effective Permeability ◽

Water Saturation ◽

Residual Water ◽

Effective Pressure ◽

Petrophysical Properties ◽

Reservoir Conditions ◽

Water Saturated

Experimental determination of the physical properties of rocks under conditions simulating in situ reservoir conditions is of great importance both for the calculation of reserves and for the interpretation of well logging data. In addition, it is also important for the preparation of hydrocarbon field development projects. The study of the processes of changes in the petrophysical properties of the reservoir under controlled conditions allows not only to determine their reliability but also to evaluate the dynamics of these changes depending on the temperature and pressure conditions of the reservoir and the water saturation of the rocks. In this work, an evaluation of the dependence of the physical properties of hydrocarbon reservoirs on their water saturation (Sw) was carried out. Residual water saturation (Swr) was created in the rocks and the properties of these rocks were compared at the states of partial (25 %) and complete water saturation (100 %). The changes in petrophysical parameters of partially water saturated rocks during the increase in effective pressure were studied and estimates of these changes were obtained. The results showed that when the effective pressure is increased, the Swr increases by an average of 6 % compared to atmospheric conditions. This is accompanied by an increase in the velocity of longitudinal (by 51.9 % on average) and lateral waves (by 37.1 % on average). As residual water saturation increases, effective permeability decreases for both standard and reservoir conditions, with, gas permeability decreasing for both dry samples (by 23 % on average) and samples with residual water saturation (effective permeability decreases by 27 % on average). HIGHLIGHTS Changes in physical properties of hydrocarbon reservoirs by determining physical properties (permeability, porosity, elastic, electrical, deformation strength) under the standard conditions and in physical modelling of reservoir conditions and processes Assessment of the effectiveness of water saturation on the physical properties of the reservoir Comparisons between the petrophysical properties of reservoir core samples in which the pore space is fully saturated with the reservoir fluid model and samples with residual water saturation Experimental determination of the physical properties of rocks under conditions simulating in situ reservoir conditions Estimation of the changes in petrophysical parameters of partial water-saturated rocks during the increase in effective formation pressure GRAPHICAL ABSTRACT

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Modeling a Weak Foundation in Interaction with Reinforced Sand Piles under a Low-Rise Building

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.906.39 ◽

2022 ◽

Vol 906 ◽

pp. 39-45

Author(s):

Tatiana Maltseva

Keyword(s):

Bearing Capacity ◽

Sand Pile ◽

Reinforced Sand ◽

Theoretical Substantiation ◽

In Situ Experiments ◽

Vertical Displacements ◽

Water Saturated ◽

Sand Piles ◽

Theory Of Viscoelasticity

One of the ways to increase the bearing capacity and stability of a water-saturated base by introducing a sand pile vertically reinforced along the contour with geosynthetic material (geogrid SSP 30 / 30-2.5) is experimentally substantiated. This constructive solution is used in low-rise construction. For the theoretical substantiation of the suggested method, it is proposed to model the interaction of a weak foundation and a reinforced sand pile on the basis of the linear theory of viscoelasticity. Calculation of vertical displacements of the pile and comparison with the results of in situ experiments is presented.

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Tracking Deformation Processes at the Legnica Glogow Copper District (Poland) by Satellite InSAR—II: Żelazny Most Tailings Dam

Land ◽

10.3390/land10060654 ◽

2021 ◽

Vol 10 (6) ◽

pp. 654

Author(s):

Paolo Mazzanti ◽

Benedetta Antonielli ◽

Alessandra Sciortino ◽

Stefano Scancella ◽

Francesca Bozzano

Keyword(s):

Negative Impact ◽

Sar Interferometry ◽

Tailings Dam ◽

In Situ Data ◽

Tailings Dams ◽

Deformation Processes ◽

Differential Sar Interferometry ◽

Consolidation Degree ◽

Shear Planes

The failures of tailings dams have a major negative impact on the economy, surrounding properties, and people’s lives, and therefore the monitoring of these facilities is crucial to mitigate the risk of failure, but this can be challenging due to their size and inaccessibility. In this work, the deformation processes at Żelazny Most tailings dam (Poland) were analyzed using satellite Ad-vanced Differential SAR Interferometry (A-DInSAR) from October 2014 to April 2019, showing that the dam is affected by both settlements (with a maximum rate of 30 mm/yr), and horizontal sliding in radial direction with respect to the ponds. The load of the tailings is pushing the dam forward along the glacio-tectonic shear planes located at depth, in the Pliocene clays, causing horizontal displacements at a rate up to 30 mm/yr, which could lead to a passive failure of the dam. The measured displacements have been compared with the ones observed by in situ data from the 90s to 2013, available in the literature. The outcomes indicate that intense localized deformations occur in the eastern and northern sectors of the dam, while the western sector is deforming evenly. Moreover, although the horizontal deformation had a slowdown from 2010 until 2013, it continued in 2014 to 2019 with recovered intensity. The upper and the recent embankments are affected by major settlements, possibly due to a lower consolidation degree of the most recent tailings and a larger thickness of compressible materials.

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An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010648x ◽

1988 ◽

Vol 46 ◽

pp. 884-885

Author(s):

D. Loretto ◽

J. M. Gibson ◽

S. M. Yalisove ◽

R. T. Tung

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Defect Density ◽

High Vacuum ◽

Ultra High Vacuum ◽

Ex Situ ◽

Metal Base ◽

In Situ Experiments ◽

Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

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Electron and ion irradiation-induced dissolution of mechanical twins in the intermetalic U3Si: An in situ HVEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155232 ◽

1989 ◽

Vol 47 ◽

pp. 652-653

Author(s):

Charles W. Allen ◽

Robert C. Birtcher

Keyword(s):

Elevated Temperatures ◽

Ion Irradiation ◽

Ion Beam ◽

National Laboratory ◽

Argonne National Laboratory ◽

Heavy Ion ◽

High Energy ◽

Mechanical Twinning ◽

In Situ Experiments

The uranium silicides, including U3Si, are under study as candidate low enrichment nuclear fuels. Ion beam simulations of the in-reactor behavior of such materials are performed because a similar damage structure can be produced in hours by energetic heavy ions which requires years in actual reactor tests. This contribution treats one aspect of the microstructural behavior of U3Si under high energy electron irradiation and low dose energetic heavy ion irradiation and is based on in situ experiments, performed at the HVEM-Tandem User Facility at Argonne National Laboratory. This Facility interfaces a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter to a 1.2 MeV AEI high voltage electron microscope, which allows a wide variety of in situ ion beam experiments to be performed with simultaneous irradiation and electron microscopy or diffraction.At elevated temperatures, U3Si exhibits the ordered AuCu3 structure. On cooling below 1058 K, the intermetallic transforms, evidently martensitically, to a body-centered tetragonal structure (alternatively, the structure may be described as face-centered tetragonal, which would be fcc except for a 1 pet tetragonal distortion). Mechanical twinning accompanies the transformation; however, diferences between electron diffraction patterns from twinned and non-twinned martensite plates could not be distinguished.

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A computer-control program for TEM in situ fatigue experiments

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155074 ◽

1989 ◽

Vol 47 ◽

pp. 620-621

Author(s):

Kenneth S. Vecchio ◽

John A. Hunt

Keyword(s):

Slow Crack Growth ◽

Computer Control ◽

Control Program ◽

Video Tape ◽

Computer Control System ◽

Transmission Electron ◽

In Situ Experiments ◽

Tremendous Amount ◽

And Control

In-situ experiments conducted within a transmission electron microscope provide the operator a unique opportunity to directly observe microstructural phenomena, such as phase transformations and dislocation-precipitate interactions, “as they happen”. However, in-situ experiments usually require a tremendous amount of experimental preparation beforehand, as well as, during the actual experiment. In most cases the researcher must operate and control several pieces of equipment simultaneously. For example, in in-situ deformation experiments, the researcher may have to not only operate the TEM, but also control the straining holder and possibly some recording system such as a video tape machine. When it comes to in-situ fatigue deformation, the experiments became even more complicated with having to control numerous loading cycles while following the slow crack growth. In this paper we will describe a new method for conducting in-situ fatigue experiments using a camputer-controlled tensile straining holder.The tensile straining holder used with computer-control system was manufactured by Philips for the Philips 300 series microscopes. It was necessary to modify the specimen stage area of this holder to work in the Philips 400 series microscopes because the distance between the optic axis and holder airlock is different than in the Philips 300 series microscopes. However, the program and interfacing can easily be modified to work with any goniometer type straining holder which uses a penrmanent magnet motor.

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Scaffolds for Drug Delivery in Tissue Engineering

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2008.1.2.1 ◽

2008 ◽

Vol 1 (2) ◽

pp. 113-123 ◽

Cited By ~ 2

Author(s):

Vikas V. Gaikwad ◽

Abasaheb B. Patil ◽

Madhuri V. Gaikwad

Keyword(s):

Drug Delivery ◽

Tissue Engineering ◽

Heart Diseases ◽

Cartilage Regeneration ◽

Tissue Growth ◽

The Body ◽

Patient Specific ◽

In Situ Gel ◽

Heart Muscle Cells

Scaffolds are used for drug delivery in tissue engineering as this system is a highly porous structure to allow tissue growth. Although several tissues in the body can regenerate, other tissue such as heart muscles and nerves lack regeneration in adults. However, these can be regenerated by supplying the cells generated using tissue engineering from outside. For instance, in many heart diseases, there is need for heart valve transplantation and unfortunately, within 10 years of initial valve replacement, 50–60% of patients will experience prosthesis associated problems requiring reoperation. This could be avoided by transplantation of heart muscle cells that can regenerate. Delivery of these cells to the respective tissues is not an easy task and this could be done with the help of scaffolds. In situ gel forming scaffolds can also be used for the bone and cartilage regeneration. They can be injected anywhere and can take the shape of a tissue defect, avoiding the need for patient specific scaffold prefabrication and they also have other advantages. Scaffolds are prepared by biodegradable material that result in minimal immune and inflammatory response. Some of the very important issues regarding scaffolds as drug delivery systems is reviewed in this article.

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Coliform transport in a pristine reservoir: modeling and field studies

Water Science & Technology ◽

10.2166/wst.1998.0124 ◽

1998 ◽

Vol 37 (2) ◽

pp. 137-144 ◽

Cited By ~ 11

Author(s):

Elisa Garvey ◽

John E. Tobiason ◽

Michael Hayes ◽

Evelyn Wolfram ◽

David A. Reckhow ◽

...

Keyword(s):

Model Development ◽

Fate And Transport ◽

Field Studies ◽

Meteorological Conditions ◽

Reservoir Modeling ◽

Vertical Circulation ◽

Quality Model ◽

Circulation Patterns ◽

In Situ Experiments

This paper reports on field studies and model development aimed at understanding coliform fate and transport in the Quabbin Reservoir, an oligotrophic drinking water supply reservoir. An investigation of reservoir currents suggested the importance of wind driven phenomena, and that both lateral and vertical circulation patterns exist. In-situ experiments of coliform decay suggested dependence on light intensity and yielded an appropriate decay coefficient to be used in CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model. Modeling confirmed the sensitivity of reservoir outlet concentration to vertical variability within the reservoir, meteorological conditions, and location of coliform source.

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