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Centrinio šildymo kieto kuro katilo ,,Kalvis - 4D'' parametrų tyrimas / Reaserch parameters of central heating solid fuel boiler ,,Kalvis – 4D’’Stašys, Gintaras 31 August 2012 (has links)
Šiame darbe pateikti kuro kaloringumo priklausomybės nuo drėgmės skaičiavimai. Atlikus bandymus, nustatyta katilo nominali ir minimali galia. Skaičiuojant tiesioginiu ir netiesioginiu metodu nustatytas katilo naudingumo keficientas. Atlikta katilo korpuso įtempimo būvio analizė. Buvo skaičiuojama katilo šiluminė varža, pateikti pasiūlymai katilo techninių parametrų gerinimui. / This paper presents the dependence on fuel moisture calorie calculations, tests the boiler nominal and minimum power. Calculation of direct and indirect method keficientas the boiler. Boiler body made of life stress analysis. The calculated resistance of the boiler įiluminė, proposals to improve technical parameters of the boiler.
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Návrh zásobníku pro sypké materiály / Project of silo for powdery materialsMatuška, Michal January 2015 (has links)
This diploma thesis is deals with proposal of silo for various powdery materials. In the thesis is there calculation of type construction, design of the main dimensions and strength calculation of the wall thickness of the silo. There are also described active and passive stress state in the silo and their influence on loading and emptying. Then there is an overview of possible modifications the silo and other possible equipment.
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Interprétation de mesures de déformation en forage en terrain anisotrope : retour d’expérience de l’utilisation de cellules CSIRO dans l’argilite de Tournemire (Aveyron) / Interpretation of the hole's strain measurements in anisotropic field : feedback from the use of CSIRO cells in the Tournemire argillite (Aveyron)Ben Ouanas, Abdelmonem 26 November 2010 (has links)
En géomécanique, la caractérisation de l’état de contrainte et de la rhéologie d’un massif rocheux peut être obtenue en mesurant la réponse en déformation du terrain sous l’effet d’une sollicitation connue. Une méthode parmi d’autres consiste à recourir pour cela à une cellule de mesure intégrée (comportant des capteurs de déformation orientés selon différentes directions) installée dans un forage et rendue solidaire du massif par l’intermédiaire d’une colle époxy. Ce principe de mesure est utilisé, notamment, pour déterminer l’état de contraintes in situ par la méthode dite de « surcarottage » et les caractéristiques élastiques de la roche à partir de l’essai « biaxial ».Entre novembre 2005 et janvier 2006, une campagne d’essais géomécaniques de ce type a été menée dans l’argilite de Tournemire (Aveyron, France), à l’aide des cellules CSIRO. Les mesures de déformation obtenues ont révélé des phénomènes inhabituels qui ont rendu délicate la détermination des caractéristiques élastiques anisotropes de la roche et impossible l’accès aux contraintes du site.La présente thèse a pour objectif de contribuer, par la recherche d’explications à l’origine de ces phénomènes, d’une part, à l’amélioration de la connaissance du comportement de l’argilite de Tournemire et, d’autre part, à l’amélioration du protocole de mesure et d’interprétation de déformations obtenues par cellules CSIRO.Notre démarche consiste, dans un premier temps, à émettre un certain nombre d’hypothèses explicatives des phénomènes observés par la recherche bibliographique. Dans un deuxième temps, nous testons ces hypothèses à travers la modélisation analytique et numérique des essais de surcarottage et biaxiaux, puis à travers la réalisation de nouvelles expérimentations in situ et en laboratoire sur l’argilite, mais aussi sur des matériaux-tests (ciment, échantillon de colle).Nous concluons que les phénomènes inhabituels observés résultent, pour l’essentiel, des conditions de mise en œuvre in situ des cellules CSIRO. En particulier, nous mettons l’accent sur les artéfacts induits par le comportement visco-plastique de la colle époxy lorsqu’elle n’est pas parfaitement polymérisée. Le rôle de l’endommagement de la roche généré par les opérations de forage est également discuté. Nous en tirons des recommandations pratiques pour la réalisation de nouveaux essais dans des conditions similaires / In Geomechanics, determining the state of stress and the rheology of rock massive can be obtained by measuring the strain response of the ground under the effect of a known stress. A method among others is to use a cell integrated (with strain gauges oriented in different directions) installed in a borehole and secured to the mass through an epoxy glue. This measurement is used, notably, to determine the stress state in situ by the « overcoring » method and the elastic parameters of the rock from the « biaxial » test.Between November 2005 and January 2006, a geomechanical testing campaign was conducted in the argillaceous formation of the Tournemire experimental site (Aveyron, France) using CSIRO Hi cells. The strain measurements obtained during overcoring and biaxial tests, have shown unusual phenomena, which have made difficult the determination of anisotropic elastic parameters of the rock and the access to the site stress.Therefore, through researches for explanations of the origin of these phenomena, this thesis aims to improve and to contribute to the understanding of argillite Tournemire’s behaviour and to upgrade the measurement protocol as well as the interpretation of cells CSIRO’s strain.Our approach is, firstly, to issue a number of hypotheses to explain certain, phenomena observed in literature. In a second step, we test these hypotheses through analytical and numerical modelling of the biaxial and overcoring tests then through the realization of new experiments in situ within laboratory on argillite, and also on materials tests (cement, sample of glue).We conclude that the unusual phenomena observed are essentially the result of the conditions for implementing in situ CSIRO’s cell. In particular, we focus on the artefacts induced by the visco-plastic behaviour of the epoxy glue when it is incompletely polymerised. The role of damage on the rock generated by drilling operations is also discussed. We draw some practical recommendations for implementing new tests under similar conditions
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Evolution des propriétés physiques des sédiments et des zones de failles du front de déformation à la zone sismogène : cas de la marge de Nankai / Evolution of the sediments and fault zones physical properties from the deformation front to the seismogenic zone : study of the Nankai marginConin, Marianne 03 May 2011 (has links)
Cette thèse porte sur les relations entre la limite supérieure de la zone sismogène et la construction et la structuration du prisme de Nankai, au Sud-Est du Japon. La détermination des contraintes dans le prisme à partir des données d’ovalisation de puits montrent une permutation des contraintes au dessus d’un hors séquence, appelé splay fault, situé à la limite de la zone sismogène. Le régime de contrainte est extensif dans cette zone et décrochant dans le reste du prisme. L’étude de la compaction des sédiments à partir des données de porosité corrigée de l’effet des argiles permet de quantifier l’érosion récente des sédiments de pentes, et montre l’existence d’une érosion plus ancienne au dessus des chevauchements majeurs. L’étude des styles de déformations des sédiments montre que l’érosion peut rendre compte de la répartition des structures de déformation dans le prisme. Enfin, la modélisation mécanique de la marge montre que l’activité de la splay fault, très faible depuis le dernier million d’années, et la présence d’une zone d’extension en arrière de cette faille s’expliquent par l’arrêt de l’accrétion et un décollement faible dans le prisme frontal. / This study is focused on the upper limit of the seismogenic zone in the Kumano transect of the Nankai margin in relation with the construction of the wedge. The first step was to determine the stress orientations and amplitude within the wedge from borehole breakouts analysis. We show the striking presence of a trench normal extension zone behind the splay fault in a wedge dominated by a strike-slip stress regime. Locally an extensional stress regime is also observed in the slope sediment of the outer part of the wedge. In a second part of this work, we used porosity corrected from water bound to clay minerals to study the compaction state of the sediments and to quantify the amount of erosion in the slope sediments. Results also highlight the existence of past erosion related to the activity of the splay fault. In a third part, the observation of deformation style within sediments showed that erosion could explain the distribution of dilatant and compactive structures within the wedge. Finally, we show, based on mechanical modeling, that the splay fault slow slip rate over the last million year, and the presence of an extension zone landward of the splay fault, could both be explained by a pause in the accretion and a weak décollement beneath the outer wedge.
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Strength of Megathrust Faults: Insights from the 2011 M=9 Tohoku-oki EarthquakeBrown, Lonn 27 August 2015 (has links)
The state of stress in forearc regions depends on the balance of two competing factors: the plate coupling force that generates margin-normal compression, and the gravitational force, that generates margin-normal tension. Widespread reversal of the focal mechanisms of small earthquakes after the 2011 Tohoku-oki earthquake indicate a reversal in the dominant state of stress of the forearc, from compressive before the earthquake to tensional afterwards. This implies that the plate coupling force dominated before the earthquake, and that the coseismic weakening of the fault lowered the amount of stress exerted on the forearc, such that the gravitational force became dominant in the post-seismic period. This change requires that the average stress drop along the fault represents a significant portion of the fault strength. Two cases are possible: (1) The fault was strong and the stress drop was large or nearly-complete (e.g. from 50 MPa to 10 MPa), or (2) that the fault was weak and the stress drop was small (e.g. from 15 MPa to 10 MPa). The first option appears to be consistent with the dramatic weakening associated with high-rate rock friction experiments, while the second option is consistent with seismological observations that large earthquakes are characterized by low average stress drops. In this work, we demonstrate that the second option is correct. A very weak fault, represented by an apparent coefficient of friction of 0.032, is sufficient to put the Japan Trench forearc into margin-normal compression. Lowering this value by ~0.01 causes the reversal of the state of stress as observed after the earthquake. A slightly stronger fault, with a strength of 0.045, does not agree well with the observed spatial extent of normal faulting for the same coseismic reduction in strength. We also calculate distributions of stress change on the fault and average stress drop values for the Tohoku-oki earthquake, as predicted from 20 published rupture models which were constrained by seismic, tsunami, and geodetic data. Our results reconcile seismic observations that average stress drops for large megathrust events are low with laboratory work on high-rate weakening that predicts very high or complete stress drop. We find that, in all rupture models, regions of high stress drop (20 – 55 MPa) are probably indicative of dynamic weakening during seismic slip, but that the heterogeneous nature of fault slip does not allow these regions to become widespread. Also, coseismic stress increase on the fault occurs in many parts of the fault, including parts of the area that experienced high slip (> 30 m). These two factors ensure that the average stress drop remains low (< 5 MPa). The low average stress drop during the Tohoku earthquake, consistent with values reported for other large earthquakes, makes it unambiguous that the Japan Trench megathrust is very weak. / Graduate
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Návrh zásobníku pro sypké materiály / Project of silo for powdery materialsKadyrgozhin, Yermek January 2020 (has links)
The principle of this thesis is to design of the silo for bulk materials. In the thesis is there an analysis of the choice of type and construction of the silo, design of main dimensions and strength calculation of the silo. Then there is described active and passive stress state of the silo and their influence on filling and emptying. The thesis deals the possibility of the formation of buckling vault (bridging) during emptying and ways to solve it. There are also described various possibilities of modifications and equipment of the silo in relation to the type of material.
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Zesilování železobetonových sloupů ovinutím FRP tkaninou / Strengthening reinforced concrete column confined by FRP fabricKostiha, Vojtěch January 2018 (has links)
The doctoral thesis deals with the strengthening of reinforced concrete columns by FRP fabric wrapping. Its aim is to describe the principles of confinement based on the analytical study, numerical simulations and the results of the experimental program. The description of the confinement philosophy is made with respect to the type of FRP material used. It was therefore possible to present a design process of confinement, which accurately predicts the behaviour of the confined columns. At the same time, some effects limiting the effect of confinement (e.g. the method of wrapping, the number of FRP fabric layers, the slenderness of the element, etc.) are included in the design. The dissertation also presents basic information about FRP material and its properties and gives an overview of design approaches of the FRP confined columns. The dissertation also pointing out the shortcomings of the design code ČSN EN 1992-1-1. The stated example highlights the significant variation in properties of confined concrete determined by selected approaches. This variation of properties complicates the design of this strengthening method. The experimental program was used to verify the basic principles of confinement and, through high columns, allowed a description of the behaviour in almost the whole range of interaction diagram. The conclusions of the work provide information on possible future research direction.
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