82 research outputs found
Study of the inverse problem in the estimation of heat transfer coefficients in spray cooling
No full textvon Dimitar Dontche
Untersuchung inverser Probleme zur Bestimmung von Wärmeübergangskoeffizienten bei der Sprühkühlung
No full textHeat transfer, inverse problem, spray coolingMagdeburg, Univ., Fak. für Verfahrens- und Systemtechnik, Diss., 2007von Dimitar Dontche
Finite element analysis of flexural cracking behavior of RC structures, strengthened by externally bonded CFRP
No full textFE simulation of damage and crack initiation
and propagation in RC structure, externally strengthened by CFRP will be presented.
Constitutive law, based on the model of Mazars is used for the simulation of the
non-linear concrete behavior. In the proposed incremental procedure the regions,
affected by damage will be remeshed at each step and the initial mesh will be refined.
Numerical results will be compared with experimental results obtained by CFRP
strengthened RC beam subjected to a bending
Is unitary and integral Yugoslavia possible?
No full textTitle: Bъзмοжнa πu e euòннa u uяπocmнa Юƨocπaeuя? Ha ƨpaнuyama мeжòy noπumuκama u фuπocoфuяma (Is unitary and integral Yugoslavia possible? On the borderline between politics and philosophy) Originally published: in the magazine Фuπocoфcκu npeƨπeò, IV, 1932, vol. III, pp. 197–227. Language: BulgarianThe excerpts used are from the original, pp. 213–214, 220, 221–223. About the author Dimitar Mihalchev [1880, Lozengrad (Tur. Kirklareli, present-day Turkey) – 1967, Sofia]: philosopher and diplom..
THE IDIOLECT OF REVEREND ECONOMOS DIMITAR POPNIKOLOV PETKANOV
No full textA less studied talented author and brother of the popular fiction writer Konstantin Petkanov, priest
Dimitar wrote in the 1950s. This publication analyzes several parameters of his idiolect: phonetic peculiarities (reflex of ѣ, ѫ,
ъ; epenthetic [l]; reflexes of the [tʃ] [dʒ] groups; phonetic dialectisms; phonetic doublets); morphological paradigm (case
inflections; noun form for number; dualis; nomina collectiva; extended Church Slavonic suffix for adjectives; dialectal and
contracted pronoun forms; a temporal system characterized by high frequency of the verbs in terms of origin, distribution and
stylistic differentiation); lexical specifics (in terms of origin, distribution and stylistic differentiation). Emphasis is placed on
those lexical layers that constitute and ditinguish the author’s language. Hapaxes (produced using morphological and non-
morphological methods), rare words, semantic transponents, dialectisms, colloquial vocabulary and foreign words are studied.
All linguistic phenomena are examined retrospectively and in comparison with the synchronous linguistic situation before and
after the orthographic reform of 1945 in order to highlight the innovative contribution and the mechanisms through which the
author enriched the contemporary Bulgarian vocabulary. Occasionalisms, dialectal and archaic units occur more often in
Petkanov’s poetic works than in his fiction. The source material has been excerpted from Volume 1 (January – March) and
Volume 2 (April – June) of the hagiographic tetralogy “The Year of Our Lord“ and the memoir “A Book about My Brother –
the Writer Konstantin N. Petkanov“, which were published a few years ago by Dimitar Petkanov’s heirs
Imperium Militiae(I)
No full textThe most common idea in Romance studies is that Romans, as practical people, didn’t conduct theoretical research on their country or their army, but they gradually built them both. Meanwhile, they reformed and upgraded it, so that they could respond to the challenges of their age. Moreover, the basis of their research was not explicit doctrines, or prior concepts, in fact they used their own, or the experience of others, to find concrete solutions to daily problems. Just as the Hellenic romanophile Polibius (200-120 B.C), in his work Historia, asks the crucial question: ”Is it possible to have such an unreliable man who is not interested in how the Romans, with their unicipal structure, managed to conquer the whole world”? - in the same way the author of this paper, as much as its content allows, humbly and unpretentiously tries to answer the crucial question: “What kind of military structure
created and defended one of the biggest and most enduring empires in world’s history, and what rules governed it”
Effet de confinement par matériaux composites sur le comportement mécanique en compression des éléments en béton
No full textUne méthode pour la simulation de propagation de fissure tridimensionnelle est proposée pour les sollicitations de fatigue. La vérification de la minimisation de l'énergie totale de la structure élastique linéaire, lors d'une propagation de fissure quasi-statique, est exprimée sous forme variationnelle. Cette écriture conduit à la résolution d'un système non-linéaire, menée par une méthode de Newton faisant intervenir les dérivées première et seconde de l'énergie totale. Une nouvelle formulation de la loi de Paris sous forme d'énergie de rupture équivalente permet, en utilisant la méthode G-thêta, d'obtenir les dérivées de l'énergie totale lors d'un problème de fatigue. Cette approche, mise en oeuvre au sein du code éléments finis ZéBuloN, est utilisée dans un test de validation, puis pour la simulation tridimensionnelle de la fissuration d'un disque de turbine
Study of the mechanical behavior of reinforced concrete column-corbel assembly reinforced or repaired by bonded composite materials
No full textLes assemblages poteau-console courte en béton armée sont très souvent utilisés dans le domaine de génie civil. L’objective de cette thèse en cotutelle et d’étudier le comportement mécanique de l'assemblage poteau-console courte en béton armé renforcé ou réparé par des matériaux composites en tissus de fibres de carbone. Cette étude est une continuation des travaux effectués sur consoles courte en béton armée au sein de l’équipe de génie civil à l’université de Reims champagne Ardenne fait partie de l’Institut de Thermique, Mécanique, Matériaux (ITheMM). Une étude expérimentale sur le comportement mécanique de l’assemblage poteau-console courte en béton armé à l’aide d’une dalle d’essai avec capacité portante de 100 tonnes a été réalisée. De plus la structure a été instrumentée par des jauges des déformations pour mesurer les déformations locales. L’étude numérique par éléments finis est réalisée en utilisant un schéma de résolution Dynamique-explicite. Des analyses comparatives sont effectué pour déterminé les paramètres d’endommagement des matériaux constitutive et pour choisir la meilleure stratégie de simulation. Cela nous permit de bien calibrer les modèles. Une fois les modèles validés par l’étude expérimentale, nous avons prolongé le poteau pour obtenir notre modèle d’assemblage poteau-console courte. Les résultats ont montré que le modèle proposé simule avec succès les réponses expérimentales de la structure hybride poteau-console en BA renforcée par tissus de matériaux composite en termes de résistance au cisaillement, flexion et flambement. Les différents modes de rupture ont été étudiés et compares avec celles observés lors des études expérimentales. Une étude paramétrique a été ensuite réalisée sur la base du modèle proposé.Study of the mechanical behavior of reinforced concrete column-corbel assembly reinforced or repaired by bonding composite materialsThe reinforced concrete column-corbel assemblies are widely used in the field of industrial and civil construction. The aim of the dissertation is to study the mechanical behavior of this assembly reinforced with carbon fabric composite materials. This study is a sequel of the previous one on corbels carried out in the ‘Institute of Thermal, Mechanics, Materials (ITheMM EA 7548) at the University of Reims. An experimental study was conducted on the mechanical behavior of the column-corbel joint along with an experimental setup with a capacity of 100 t and a support distance of 20 m. In addition, sensors that detect local deformations were glued to the structure.Computational modeling by the finite element method was conducted, using a dynamic explicit system for solving the equations. A comparative analysis of the parameters of the materials’ defectiveness was carried out in order to be selected the appropriate modeling strategy.This enabled the model to be calibrated properly. After validating the simulation along to the experimental data, we extended the column length to obtain the required assembly.The obtained results observe that the proposed simulation successfully represents the behavior of the joint reinforced with composite materials, in terms of shear, bending and buckling modes.Different types of defectiveness were considered and compared with the experimental studies.Subsequently, a parametric study was carried out, based upon the proposed numerical model.Keywords: Reinforced concrete, Column, Corbel, Reinforcement, Composite materials, CFRP strengthening, Mechanical behavior, Nonlinear behavior, Damage, Fracture, FE modelin
Mechanical Pathologies of Reinforced and Damaged Concrete Corbels by Gluing Composite Carbon Fabrics Under Static and Dynamic Tests
No full text
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