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Evaluation of fracture response of Silesian granite specimens via Effective Crack Model approach and finite element analysis
Malíková, L.; Vavro, Leona; Vavro, Martin; Keršner, Z.
2019 - English
The paper is focused on the advanced evaluation of fracture tests of selected rock specimens. Assessment of fracture response of chevron notch cylindrical specimens of Silesian granite subjected to three-point bending test was performed. The effective crack model is used and academic software chevroncylinder (author Petr Frantík) based on the finite element method is applied for the analyses. Based on the described procedures, estimation of maximum values of the effective fracture toughness are established and discussed.
Keywords:
granite; fracture test; chevron notch; load–displacement diagram; effective crack model
Available in digital repository of the ASCR
Evaluation of fracture response of Silesian granite specimens via Effective Crack Model approach and finite element analysis
The paper is focused on the advanced evaluation of fracture tests of selected rock specimens. Assessment of fracture response of chevron notch cylindrical specimens of Silesian granite subjected to ...
Tourist interest in illicit zone of ice caves
Nováková, Eva; Kuda, František; Kubalíková, Lucie
2018 - English
Ledové sluje (Ice Caves) in the Podyjí National Park represents one of the most spectacular sites within the area. It consists of the large boulder field and several pseudokarst caverns on the north-western slope of the ridge that are very important from the ecological and geomorphological point of view. The access to the site is restricted for the visitors of National Park as there exists a risk of damage and disturbance of these unique phenomena, tourist can use the marked paths leading around the site, they can reach the top part of the ridge. Currently, there are only several persons who have legal access to the site (employees of the National Park Administration and other researches with the permission issued by NP Administration). However, the installed sensor that counts the passages proved that the site is visited more frequently than it should be. The number of people who visit this site (situated within the first zone of National Park where there is no marked path and so the access is forbidden by decree) is quite alarming. Based on these findings, some proposals for the solution of this unfavourable situation are proposed and other possibilities how to avoid this undesirable phenomenon are discussed.\n
Keywords:
Podyji National Park; restricted area; passages monitoring
Available in a digital repository NRGL
Tourist interest in illicit zone of ice caves
Ledové sluje (Ice Caves) in the Podyjí National Park represents one of the most spectacular sites within the area. It consists of the large boulder field and several pseudokarst caverns on the ...
Stabilita chodeb při dobývání uhlí metodou komora-pilíř ve velkých hloubkách
Šňupárek, Richard; Waclawik, Petr; Kukutsch, Radovan
2018 - Czech
Za účelem ověření napěťo-deformačních projevů dobývání metodou chodba-pilíř v hloubce až 900 m pod povrchem byl implementován rozsáhlý systém geotechnického monitoringu a sledování deformací a pohybu povrchu. Na základě výsledků napěťo-deformačního monitoringu byla provedena podrobná analýza stability chodeb z hlediska konvergence, deformačního chování okolního horninového masivu a funkce použité výztuže ve dvou sledovaných oblastech s rozdílnými geologickými i provozními podmínkami. In order to verify the stress-strain state of mining using the room and pillar method at a depth of up to 900 m below the surface, an extensive system of geotechnical monitoring and observation of deformations and surface movement was implemented. Based on the results of the stress-strain monitoring, detailed analysis of roadway stability from the point of view of the convergence, deformation behavior of the surrounding rock mass and the function of the reinforcement used in the two monitored areas with different geological and operational conditions was carried out.
Keywords:
room and pillar; monitoring; roadways stability
Available in a digital repository NRGL
Stabilita chodeb při dobývání uhlí metodou komora-pilíř ve velkých hloubkách
Za účelem ověření napěťo-deformačních projevů dobývání metodou chodba-pilíř v hloubce až 900 m pod povrchem byl implementován rozsáhlý systém geotechnického monitoringu a sledování deformací a pohybu ...
Geotourism within urban areas: New ways of promotion of natural and cultural heritage (Case study from Brno City).
Kubalíková, Lucie; Bajer, A.
2018 - English
Geotourism is based especially on geodiversity, but it also uses the cultural-historical aspects of an area, it is linked to the education and counts with active engagement of local people. Currently, geotourism is developed mainly within rural areas, but there are activities that point on the geodiversity and its importance within urban areas. Rational and sustainable use of geodiversity within urban areas can represent an alternative to the traditional tourist destinations and contributes to the understanding of the importance and necessity of protection of geodiversity itself. Geodiversity, respectively geoheritage within urban areas does not include only issues of primary (natural) geodiversity (substrate, Iandforms, soils), but also anthropogenic landforms and processes (secondary geodiversity), hydrological features (wells, millraces) and geodiversity ex-situ (museum collections, building material). The paper presents this new form of tourism and gives examples of selected geodiversity/geoheritage features within the Brno city.
Keywords:
geodiversity; geoheritage; urban geotourism; Brno
Fulltext is available at external website.
Geotourism within urban areas: New ways of promotion of natural and cultural heritage (Case study from Brno City).
Geotourism is based especially on geodiversity, but it also uses the cultural-historical aspects of an area, it is linked to the education and counts with active engagement of local people. Currently, ...
Stabilita chodeb při dobývání uhlí metodou chodba-pilíř ve velkých hloubkách
Šňupárek, Richard; Waclawik, Petr; Kukutsch, Radovan
2018 - Czech
Za účelem ověření napěťo-deformačních projevů dobývání metodou chodba-pilíř v hloubce až 900 m pod povrchem byl implementován rozsáhlý systém geotechnického monitoringu a sledování deformací a pohybu povrchu. Na základě výsledků napěťo-deformačního monitoringu byla provedena podrobná analýza stability chodeb z hlediska konvergence, deformačního chování okolního horninového masivu a funkce použité výztuže ve dvou sledovaných oblastech s rozdílnými geologickými i provozními podmínkami. In order to verify the stress-strain manifestations of the corridor-pillar excavation at a depth of up to 900 m below the surface, an extensive system of geotechnical monitoring and observation of deformations and surface movement was implemented. Based on the results of the stress-strain monitoring, detailed analysis of corridor stability from the point of view of the convergence, deformation behavior of the surrounding rock mass and the function of the reinforcement used in the two monitored areas with different geological and operational conditions was carried out.
Keywords:
corridor-pilar; geotechnical monitoring; deformations and surface movement
Available in a digital repository NRGL
Stabilita chodeb při dobývání uhlí metodou chodba-pilíř ve velkých hloubkách
Za účelem ověření napěťo-deformačních projevů dobývání metodou chodba-pilíř v hloubce až 900 m pod povrchem byl implementován rozsáhlý systém geotechnického monitoringu a sledování deformací a pohybu ...
Geodiverzita, sekundární gediverzita a kulturní dědictví
Kirchner, Karel; Kubalíková, Lucie; Kuda, František; Havlíček, M.; Machar, I.; Pechanec, V.
2018 - Czech
V rámci projektu NAKI II - Kulturní dědictví krajiny Arcidiecéze olomoucké - výzkum, prezentace a management (DGB 16P02B014) se zaměřujeme na výsledky, které přispějí k udržitelnému rozvoji regionální kulturní identity prostřednictvím aplikovaného výzkumu kulturního dědictví v kulturní krajině studované oblasti. Součástí hmotného kulturního dědictví jsou tvary reliéfu, které vznikly vědomou činností člověka - antropogenní tvary reliéfu. Tyto antropogenní tvary doplňují geodiversity krajiny a jsou označovány jako sekundární geodiversita, jejich identifikace a interpretace umožní doplnit a zvýšit rozmanitost kulturního dědictví a upřesnit rozvoj kulturní krajiny. První výsledky z Arcidiecéze olomoucké jsou prezentovány. Within the framework of the NAKI II project – Cultural heritage of landscape of the Archdiocese of Olomouc - research, presentation and management (DGB 16P02B014), we focus on the results that will contribute to the sustainable development of regional cultural identity through applied cultural heritage research in the cultural landscape of the area of interest. As part of the material cultural heritage, we include the landforms that originated from the conscious activity of man - the anthropogenic relief forms. These landforms complement the geodiversity of the landscape and are referred to as secondary geodiversity, their identification and interpretation will make it possible to complement and enhance the diversity of cultural heritage and to specify the development of the cultural landscape. The first results from the Archdiocese of Olomouc are presented.
Keywords:
geodiversity; secondary geodiversity; cultural heritage; Archdiocese of Olomouc
Fulltext is available at external website.
Geodiverzita, sekundární gediverzita a kulturní dědictví
V rámci projektu NAKI II - Kulturní dědictví krajiny Arcidiecéze olomoucké - výzkum, prezentace a management (DGB 16P02B014) se zaměřujeme na výsledky, které přispějí k udržitelnému rozvoji regionální ...
Použití modelu efektivní trhliny k analýze odezvy válcových těles se šípovým zářezem
Halfar, P.; Frantík, P.; Šimonová, H.; Daněk, P.; Keršner, Z.; Vavro, Leona; Vavro, Martin
2018 - Czech
Příspěvek uvádí aplikaci modelu efektivní trhliny k analýze odezvy válcových těles se\nšípovým zářezem namáhaných v tříbodovém ohybu. Jednalo se o testy tří zkušebních\ntěles z pískovce z lokality Javorka a tří betonových těles z nosné konstrukce nádražní\nbudovy v Ostravě-Vítkovicích. K výpočtům byl použit akademický software\nchevroncylinder na bázi metody konečných prvků. This paper introduces the application of an effective crack model to analyse the response\nof chevron-notched cylindrical specimens loaded in three-point bending. There were\nanalysed the three sandstone specimens from the Javorka locality and three concrete\nspecimens from the building structure of the Ostrava-Vítkovice railway station. The\nchevroncylinder software based on the finite element method was used for the\ncalculations.
Keywords:
fracture test; effective crack model; chevroncylinder software; sandstone; concrete
Available in digital repository of the ASCR
Použití modelu efektivní trhliny k analýze odezvy válcových těles se šípovým zářezem
Příspěvek uvádí aplikaci modelu efektivní trhliny k analýze odezvy válcových těles se\nšípovým zářezem namáhaných v tříbodovém ohybu. Jednalo se o testy tří zkušebních\ntěles z pískovce z lokality ...
Assessment of anthropogenic landforms for the geotourism purposes (case study: Velké Opatovice fortification site, Archdiocese of Olomouc, Czech Republic)
Kirchner, Karel; Kubalíková, Lucie; Machar, I.
2018 - English
The human impact on the relief is often very devastating: natural landforms are modified, damaged or destroyed and the intensity of human-induced processes even surpasses the natural ones. However, people also create new landforms which are interesting from geoconservation, educational, cultural and historical points of view. Thanks to these aspects, they also have a potential for geotourism, geoeducation and recreation. For the assessment of anthropogenic landforms (respectively anthropogenic geosites and geomorphosites), a method based on the concept of geomorphosties and taking into account the holistic approach to geotourism, is proposed. The article presents an example of anthropogenic landforms on geo-cultural site Velke Opatovice fortification site situated in the western part of the Archdiocese of Olomouc. Based on the detailed fieldwork, the inventory of landforms and other features, the assessment and some proposals for geotourist use of the site are presented.
Keywords:
geo(morpho)sites; cultural heritage; Archdiocese of Olomouc
Available in a digital repository NRGL
Assessment of anthropogenic landforms for the geotourism purposes (case study: Velké Opatovice fortification site, Archdiocese of Olomouc, Czech Republic)
The human impact on the relief is often very devastating: natural landforms are modified, damaged or destroyed and the intensity of human-induced processes even surpasses the natural ones. However, ...
Implicit constitutive solution scheme for Mohr-Coulomb plasticity
Sysala, Stanislav; Čermák, M.
2017 - English
This contribution summarizes an implicit constitutive solution\nscheme of the elastoplastic problem containing the Mohr-Coulomb yield cri-\nterion, a nonassociative \now rule, and a nonlinear isotropic hardening. The\npresented scheme builds upon the subdifferential formulation of the \now rule\nleading to several improvements. Mainly, it is possible to detect a position\nof the unknown stress tensor on the Mohr-Coulomb pyramid without blind\nguesswork. Further, a simplifed construction of the consistent tangent opera-\ntor is introduced. The presented results are important for an efficient solution\nof incremental boundary value elastoplastic problems.
Keywords:
Mohr-Coulomb plasticity; implicit constitutive solution scheme; consistent tangent operator
Fulltext is available at external website.
Implicit constitutive solution scheme for Mohr-Coulomb plasticity
This contribution summarizes an implicit constitutive solution\nscheme of the elastoplastic problem containing the Mohr-Coulomb yield cri-\nterion, a nonassociative \now rule, and a nonlinear ...
Overlapping domain decomposition preconditioners for elliptic and parabolic problems in primal and mixed form
Blaheta, Radim
2017 - English
In this lecture, we concern the numerical solution of PDE problems and describe overlapping domain decomposition, which provides a tool for the construction of parallelizable Schwarz type iterative solvers and preconditioners. The idea of using overlapping domain decomposition goes back to Schwarz alternating method from 1870, see [1]. The analysis of this alternating iterative method was evolved by great mathematicians, see e.g. S.L. Sobolev (1936), R. Courant and D. Hilbert (1937), S.G. Michlin (1951), M. Práger (1958), I. Babuška (1958), F.E. Browder (1958). The use of overlapping domain decomposition for parallel computations started in the late eighties in the work of M. Dryja and O. Widlund [4], P.L. Lions [5, 6], S. Nepomnyaschikh [7] and others and continue up to the present days. The origin of the alternating Schwarz method is nicely described in [8].
Keywords:
preconditioners; Schwarz method; matrix Ma
Fulltext is available at external website.
Overlapping domain decomposition preconditioners for elliptic and parabolic problems in primal and mixed form
In this lecture, we concern the numerical solution of PDE problems and describe overlapping domain decomposition, which provides a tool for the construction of parallelizable Schwarz type iterative ...
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