In this report protocols for 3D and 4D analyses of microstructure of geological and mineralogical samples are given, which is aligned with the main objectives of the project J1-7148 entitled »3D and 4D microscopy - development of new powerful tools in geosciences«. The main goal of the project J1-7148 is to develop and implement protocols for optimal 3D microscopy, which include imaging on laboratory based microtomograph microXCT 400 (XRADIA) situated at ZAG, 3D image analysis with software AVIZO (FEI) and if necessary analysis with complementary techniques such as SEM, Hg porosimetry, gas soprtion and optical microscopy. With dynamic structural processing (microtomographic imagins simultaneous with mechanical and temperature loading) we developed also protocols for 4D microscopy. These protocols enable more standardized, achievable, usable and less time consuming and cheaper spatial analysis of geological and mineralogical materials. The following protocols are given in the report: - Protocol for 3D image analysis of pores (Chapter 2); - Protocol for image stitching and imaging at different resolution (Chapter 3); - Protocol for the 3D mineralogical analysis (Chapter 4); - Protocol for spatial imaging of low attenuation phases and high attenuation phases (phase contrast) (Chapter 5); - Protocol for dynamic microstructural processing (Chapter 6) and - Protocol for transfer of microtomographic data sets in different 3D geological tools (Chapter 7). Given protocols are developed based on testing of actual geological samples such as rocks, ores, as well as other mineralogical samples, such as concrete, sediments, teeth and similar.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 2433639Authigenic calcitic mineralization often occurs in lignite layer of Velenje basin. They occur in two main lithotypes of Velenje lignite: xylite and gehlite, which have different amount of xylite component. Based on macroscopic observations six different structural types of mineralisation occur: (1) mineralisation in the form of lamina and thin layers; (2) mineralisation in the form of small lenses and small lens bodies; (3) densely dispersible mineral matter in fine grained detritic material; (4) mineralisation in the form of replacement of xylithic fragments; (5) mineralisation in the form of incrustations of the xylithic fragments; and (6) mineralisation in the form of yellowish flowstone in the form of secondary fillings of voids. Understanding of the geometry of mineralisation, their extent and their 3D distribution in lignite is important for understanding of mineralisation genesis as well as for understanding of geomechanical and other characteristics of mineralised lignite. In this paper we present first results of microtomographic examinations of space distribution of mineralogical domains and their interrelations on the chosen samples of Velenje lignite. Spatial microscopy was carried out with the microXCT400 microtomograph (XRADIA). For 3D image analyses we used AVIZO FIRE (FEI). The final resolution achieved on samples of 3cm in diameter was 31.6 µm.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 1435742Fibre reinforced concrete is a type of concrete which, unlike conventional concrete in its structure also contains discontinuous high tensile strength fibres. Thanks to them, it has significantly better mechanical properties than ordinary concrete. In addition to the need for uniform fibre distribution in concrete, a very important parameter, which directly influences the mechanical properties of fibre reinforced concrete, is the orientation of each individual fibre. The need for a better understanding of the influence of fibre orientation on mechanical behaviour, anisotropy of material and progression of damage, puts in centre microstructural analysis. With this development and huge improvements in X-ray tomography, 3D analysis of fibre orientation has become possible by testing concrete samples. For the purpose of this study, the samples of reinforced concrete with different proportions of industrial and recycled steel fibres were tested. For the need of fibre orientation analysis, samples of reinforced concrete were examined by computer tomography and 3D analysis of images was performed. This is the first time that this kind of analysis was performed for hybrid concrete, where tomography is used for simultaneous detection of geometrical properties of two different types of steel fibres. The aim of the study was to determine the influence of orientation and number of fibres on the post-cracking behaviour of hybrid fibre reinforced concrete.
D.10 Educational activities
COBISS.SI-ID: 2433383Three lectures with practical demonstrations of microtomographic imaging and 3D image analyses were carried out on 20.4.2016, 24.5.2017 and 30.5.2018 in the frame of the following subjects: Analyses of mineralogical materials, Technical mineralogy and Special mineralogy. Around 60 students of first grade and second grade of Geology listened to the lecture.
D.10 Educational activities
COBISS.SI-ID: 2223975The second workshop on computed microtomography, which was organized in the frame of the ARRS J1-7148 project, was held on 19.1.2016. 35 participant from industry and research gathered at the workshop. The first presentation was on the project, current challenges, which was followed by presentation of practical examples of microtomographic imaging and 3D image analyses, carried out at ZAG. Prof. Dr. Tadeja Muck presented 3D technologies of printing (invited lecture). After the workshop participants had opportunity to visit microtomographic laboratory and observe in live 3D priniting and 3D image analysis.
B.06 Other
COBISS.SI-ID: 2275687