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Turistická prezentace starých krovů v prostředí historických měst
Bláha, Jiří; Panáček, M.
2018 - Czech
Shrnutí současného stavu poznání a plošné dokumentace historických krovů v českých městech. Přehled vzdělávacích a popularizačních aktivit posledních desetiletí. Vytvoření koncepce obohacení turistických atraktivit historických měst o prohlídky historických krovů a dalších významných památek stavební historie v souvisejících půdních prostorách. Jde o vedlejší produkt dlouhodobých výzkumných aktivit zaměřených na stavební památky a péči o ně, projevy regionální kulturní diverzity a transfer historických technologických inovací v evropském prostředí. Cílem je rozšíření povědomí odborné i laické veřejnosti o tradičním stavebním tesařství, jeho mistrovských dílech, stavebním vývoji a uplatnění v městském prostředí. Zkušenosti z realizace prohlídkové trasy “Pod střechami chebských domů” zprovozněné v roce 2017. The present state of knowledge and documentation of historical roof trusses in Czech towns. An overview of the educational and leisure orientated activities of the last decades. Creating the concept of enhancing the historical towns as tourist attractions with the addition of tours accessing historical timber roofs and other significant artefacts of structural history situated in related attic spaces. It is a by-product of long-term research activities focused on building heritage identification and preservation, manifestations of regional cultural diversity and the transfer of historical technological innovations in Europe. Improvement of awareness for both professionals and the general public of traditional building carpentry, construction development and their manifestation in the urban environment. The first experiences of the realization of the tour route “Under the Roofs of the Cheb Houses” which was established in 2017.
Keywords:
carpentry; Cheb; dendrochronology; building heritage; thematic routes
Available at various institutes of the ASCR
Turistická prezentace starých krovů v prostředí historických měst
Shrnutí současného stavu poznání a plošné dokumentace historických krovů v českých městech. Přehled vzdělávacích a popularizačních aktivit posledních desetiletí. Vytvoření koncepce obohacení ...
Corrosion products phase identification using micro-Raman and FTIR
Majtás, Dušan; Mácová, Petra
2018 - English
Phase identification of corroded metal objects might be problematic because corrosion products are usually a complex mixture of different phases. Furthermore, some of present phases may be either semi-crystalline or amorphous. The most suitable procedure is to use X-ray diffraction (XRD), for identification of crystalline phases in bulk, in combination with micro-Raman spectroscopy to obtain information on smaller scale and given location. Micro-Raman spectroscopy identifies crystalline and semi-crystalline phases. The literature also reports of the application of Mössbauer spectroscopy to identify amorphous phases. In this work, the combined use of Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy is evaluated. The methods may be interchangeable to some point. But is it safe to assume that all phases present can be detected?
Keywords:
corrosion; micro-Raman spectroscopy; FTIR
Available at various institutes of the ASCR
Corrosion products phase identification using micro-Raman and FTIR
Phase identification of corroded metal objects might be problematic because corrosion products are usually a complex mixture of different phases. Furthermore, some of present phases may be either ...
The effect of micro-silica on the microscopic features of the UHPC composite and its inter-facial transition zone
Hrbek, Vladimír; Prošek, Z.; Chylík, R.; Vráblík, L.
2018 - English
The uplift of concrete overall macroscopic performance by way of alternative additives is commonly used technique. In case of ultra high performance concrete (UHPC), micro-silica is added to the mixture as a micro-filler to the structure of cement binder. As a result, the cementitious matrix macro-mechanical performance is elevated. This paper is aimed on the UHPC micro-scale enhancement by different micro-silica additive content in the mixture. More closely, the study investigate the impact of the micro-silica on the inter-facial transition zone (ITZ) between the binder matrix and basaltic aggregate.
Keywords:
high performance concrete; indentation; spectral deconvolution SEM; image analysis; ITZ
Available at various institutes of the ASCR
The effect of micro-silica on the microscopic features of the UHPC composite and its inter-facial transition zone
The uplift of concrete overall macroscopic performance by way of alternative additives is commonly used technique. In case of ultra high performance concrete (UHPC), micro-silica is added to the ...
Design of material and technological copy for repair of sgraffito decorated renders
Válek, Jan; Skružná, Olga; Wichterlová, Z.; Waisserová, J.
2018 - English
This paper deals with research in Renaissance sgraffito materials and techniques. It focuses on the replication process for original materials and application techniques used in a reconstruction of the missing parts of a sgraffito decoration depicting a Landsknecht procession on the façade of a house in Slavonice. The result of the theoretical and practical experimental work is the description and evaluation of the process of creating a material and technological copy of the original. This involved detailed material analysis, determining the provenance of and selecting suitable raw materials, design of a repair mix and its testing, and evaluation during application trials. The study has shown that, in order to achieve good results, the conclusions of material analysis have to be linked to the practical\nskills of restorers and conservators. The particular application procedures that match the requirements of the historical material and the original work can be deduced from full scale practical trials. Feedback between the design of the repair mixture and the application process made it possible to come to an optimal material and application technique. The missing parts of the sgraffito were replaced using a mortar and application technique that closely correspond to those originally used in the Renaissance.
Keywords:
sgraffito; mortar analysis; historic techniques; Slavonice
Available at various institutes of the ASCR
Design of material and technological copy for repair of sgraffito decorated renders
This paper deals with research in Renaissance sgraffito materials and techniques. It focuses on the replication process for original materials and application techniques used in a reconstruction of ...
Tradiční opracování a kvalita dřeva při opravách dřevěných konstrukcí.
Kloiber, Michal; Růžička, Petr
2018 - Czech
Rozsáhlé terénní zkušenosti při opravách dřevěných konstrukcí ukazují na dva základní limitující faktory kvality odvedené práce, které se často různými obcházejí či zjednodušují. V první řadě je to kvalita dřeva při opravách (výměny, protézy) a z ní vyplývající problémy při nedodržení doporučených kritérií pro výběr vhodného materiálu, s ohledem na dlouhodobou koexistenci nového dřeva s původním materiálem. Ve druhém případě jsou velmi vlivným faktorem způsoby opracování dřeva, kdy se pro své výhody preferované tradiční způsoby z různých důvodů nahrazují podvrhem. V tomto článku se budeme vzhledem k jeho omezenému rozsahu věnovat pouze nejkřiklavějšímu případu, a tím je opracování kulatiny tesáním. Extensive field experience with repairing timber structures shows two main limiting factors for the quality of work that are often circumvented or simplified. First, it is the quality of the timber for the repairs (replacements, additions) and the resulting problem when the recommended criteria for the selection of suitable material are not met, with regard to the long-term coexistence of the new timber with the original material. Second, a critical factor is the way in which the timber is worked - the preferred traditional working is for various reasons replaced by counterfeits. Due to the limited scope of this paper, we can only pay attention to the most blatant case, which is working of logs by hewing.
Keywords:
wooden structures; old carpentry tools; timbers
Available at various institutes of the ASCR
Tradiční opracování a kvalita dřeva při opravách dřevěných konstrukcí.
Rozsáhlé terénní zkušenosti při opravách dřevěných konstrukcí ukazují na dva základní limitující faktory kvality odvedené práce, které se často různými obcházejí či zjednodušují. V první řadě je to ...
Influence of printing and loading direction on mechanical response in 3D printed models of human trabecular bone
Doktor, Tomáš; Kumpová, Ivana; Wroński, S.; Śniechowski, M.; Tarasiuk, J.; Forte, G.; Kytýř, Daniel
2018 - English
The paper deals with investigation on directional variations of mechanical response in 3D printed models of human trabecular bone. Sample of trabecular bone tissue was resected from human donor and 3D model was obtained by X-ray computed tomography. Then a series of cubical samples was prepared by additive manufacturing technique and tested by uniaxial compression loading mode. Mechanical response was compared in nine different combinations of direction of 3D printing and loading direction. The results show neglectible influence on the deformation response in elastic region (stiffness) and significant changes of the behaviour in plastic region (stress and strain at yield point, strain at full collapse).
Keywords:
additive manufacturing; tomography; deformation response
Available at various institutes of the ASCR
Influence of printing and loading direction on mechanical response in 3D printed models of human trabecular bone
The paper deals with investigation on directional variations of mechanical response in 3D printed models of human trabecular bone. Sample of trabecular bone tissue was resected from human donor and 3D ...
Možnosti využití rentgenové tomografie ke kvantifikaci poškození teplotně namáhaného betonu
Rozsypalová, I.; Kumpová, Ivana; Daněk, P.; Šimonová, H.; Keršner, Z.
2018 - Czech
Působení vysokých teplot na beton ovlivňuje vnitřní strukturu tohoto kompozitního materiálu. V příspěvku se otevírá otázka možnosti využití výpočetní rentgenové tomografie ke kVantifikaci míry poškození betonového tělesa, které bylo odvrtáno z vybraného experimentálního panelu zatěžovaného vysokými teplotami na požární peci Centra AdMaS (Advanced Materials, Structures and Technologies) FAST VUT v Brně. Nominální hodnota maxima teploty v peci činila 1000 °C. Pokročilé zařízení TORATOM (Twinned Orthogonal Adjustable Tomograph) v Centru excelence Telč (CET) kombinuje dva páry „rentgenka–detektor“ v ortogonálním uspořádání, které umožňuje dvojnásobné zrychlení procesu sběru dat pro tomografické rekonstrukce. Zařízení má plně motorizované osy pro nastavování vzdáleností „rentgenka–vzorek–detektor“. Tím lze měnit zvětšení zhruba od 1,2× po 100× (ve speciálních případech i více). Při dané velikosti pixelů detektoru je možné měnit rozlišení CT rekonstrukcí, tj. velikost jednoho prostorového bodu modelu, od 0,2 milimetrů až po mikrometrické. Další výhodu zařízení TORATOM představuje možnost paralelního zobrazování objektu ve dvou spektrech RTG záření. Tento postup umožňuje zvýraznit rozdíly mezi materiálovými komponentami, které mají v plném RTG spektru podobný útlum. Pokud se vzorek skládá pouze ze dvou materiálů, lze tyto materiály jednoznačně odlišit. U vícesložkových materiálů lze rozdíly pouze zdůraznit. The effect of high temperatures on concrete affects the internal structure of this composite material. The paper opens the question of the possibility of using a computed X–ray tomography to quantify the degree of damage of a concrete specimen that was drilled from the selected experimental panel loaded in a fire furnace with high temperatures at the AdMaS (Advanced Materials, Structures and Technologies) research centre at Faculty of Civil Engineering Brno University of Technology. The nominal value of the maximum temperature on the heated side of the panel was 1000 °C. Advanced workstation computer X–ray tomography TORATOM at Centre of Excellence Telč (CET) is parallel imaging of an object in two spectra of X–ray radiation, that allows to highlight differences between the material components to the full X–ray spectrum similar to the attenuation of the radiation.
Keywords:
TORATOM; concrete; high temperature; computed tomography
Available at various institutes of the ASCR
Možnosti využití rentgenové tomografie ke kvantifikaci poškození teplotně namáhaného betonu
Působení vysokých teplot na beton ovlivňuje vnitřní strukturu tohoto kompozitního materiálu. V příspěvku se otevírá otázka možnosti využití výpočetní rentgenové tomografie ke kVantifikaci míry ...
Utilization of image and signal processing techniques for assessment of built heritage condition
Koudelka_ml., Petr; Koudelková, Veronika; Doktor, Tomáš; Kumpová, Ivana; Kytýř, Daniel; Valach, Jaroslav
2018 - English
Historical buildings represent invaluable heritage from the past and therefore their protection is a very important task. Assessment of their condition must not cause damage accumulation thus the least possible volume removed from the structure is essential. As many historical buildings in the Czech Republic are built using sandstone that can be considered as a typical heterogeneous system, statistical signal processing is a promising approach for determination of the representative volume element (RVE) dimensions. Such calculations can be carried out on the domain of logical arrays representing binary images of the materials microstructure. This paper deals with processing of image data obtained using SEM-BSE and high resolution flatbed scanner for determination of RVE dimensions. Advanced image processing techniques are employed and results from calculation using grayscale data are presented and compared with results calculated on the basis of color input images.
Keywords:
heterogeneous systems; natural stones; image processing; K-means clustering; representative volume element
Available at various institutes of the ASCR
Utilization of image and signal processing techniques for assessment of built heritage condition
Historical buildings represent invaluable heritage from the past and therefore their protection is a very important task. Assessment of their condition must not cause damage accumulation thus the ...
Multi-channel control system for in-situ laboratory loading devices
Rada, Václav; Fíla, Tomáš; Zlámal, Petr; Kytýř, Daniel; Koudelka_ml., P.
2018 - English
In recent years, open-source applications have replaced proprietary software in many fields. Especially open-source software tools based on Linux operating system have wide range of utilization. In terms of CNC solutions, an open-source system LinuxCNC can be used. However, the LinuxCNC control software and the graphical user interface (GUI) could be developed only on top of Hardware Abstraction Layer. Nevertheless, the LinuxCNC community provided Python Interface, which allows for controlling CNC machine using Python programming language, therefore whole control software can be developed in Python. The paper focuses on a development of a multi-process control software mainly for in-house developed loading devices operated at our institute. The software tool is based on the LinuxCNC Python Interface and Qt framework, which gives the software an ability to be modular and effectively adapted for various devices.
Keywords:
CNC; controlling; LinuxCNC; Python Interface; Python; parallel programming; Qt; PyQt; Qwt; PythonQwt; LabJack
Available at various institutes of the ASCR
Multi-channel control system for in-situ laboratory loading devices
In recent years, open-source applications have replaced proprietary software in many fields. Especially open-source software tools based on Linux operating system have wide range of utilization. In ...
Analysis of mini-jack technique for in situ measurement of strength
Kloiber, Michal; Tippner, J.; Kunecký, Jiří; Sebera, V.; Milch, J.; Hrivnák, Jaroslav
2017 - English
The paper presents a recently developed diagnostic technique for in situ determination of modulus of deformability (MODL) and conventional strength (CSL) parallel to the grain using the mini-jack inserted in bored hole. The mini-jack compression technique simulates the standard compression test, it is compared to that to examine its prediction strength (correlation coefficients). The paper shows an influence of moisture content of wood on experimental measurements using this technique. The measurement was carried out at spruce samples at three moisture contents of 12, 18 and 24%. The results of the tests prove a very good correlation of the strength determined by the proposed technique and wood density and strength determined at universal testing machine in compression parallel to the grain. The effect of the moisture content on the measurement by the mini-jack technique was proved to be significant. Beside that, the newly-developed instrument was also studied using digital image correlation (DIC) technique to analyze induced strains around the bored hole. This was studied on halved spruce samples. The DIC revealed symmetric character of the loading and significant differences between strains induced in tangential and longitudinal directions.
Keywords:
non-destructive testing; mini-jack technique; wood; in-situ testing; compression strength
Available at various institutes of the ASCR
Analysis of mini-jack technique for in situ measurement of strength
The paper presents a recently developed diagnostic technique for in situ determination of modulus of deformability (MODL) and conventional strength (CSL) parallel to the grain using the mini-jack ...
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