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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Análisis de la resistencia unitaria lateral última de micropilotes inyectados en arcillas saturadas de Cusco a través de pruebas de carga / Analysis of the ultimate lateral unit resistance of micropiles injected in saturated clays of Cusco through load tests

Molina Lovatón, Rodrigo 15 August 2019 (has links)
La presente investigación tiene por objetivo determinar la resistencia unitaria lateral última del bulbo de micropilotes ejecutados mediante inyección repetitiva (IR) a partir de pruebas de carga, en suelos arcillosos saturados del distrito de San Sebastián – Cusco, 2016. El estudio fue elaborado a partir de la información brindada por empresas especializadas en estudio de suelos, ejecución de micropilotes y pruebas de carga. Se analizaron ocho de catorce pruebas de carga realizadas en total, porque estas alcanzaron la falla. En todas las pruebas se utilizó un manómetro que midió la fuerza ejercida por cuatro gatos hidráulicos, tal como indica la norma ASTM D1143. Para obtener la resistencia unitaria lateral última del bulbo (qs), primero, se determinó la carga última, luego, a este valor se restó el aporte de carga lateral en la longitud no inyectada, y ese resultado, fue dividido entre el área lateral de contacto entre el bulbo y el suelo circundante. Se determinó que los micropilotes alcanzaron cargas últimas desde 39.40 hasta 101.30 toneladas, además, las áreas de contacto entre el bulbo y el suelo se estimaron entre 16.51 y 38.46 m2, a partir de ello, se determinó que las resistencias unitarias laterales últimas varían entre 1.29 y 3.45 toneladas por metro cuadrado. La finalidad de esta investigación es contribuir a la mejor estimación de la resistencia unitaria lateral última del bulbo de micropilotes tipo IR en arcillas saturadas con número de SPT entre 19 y 28. / The objective of this research is to determine the ultimate lateral unitary resistance of the bulb of micropiles executed by repetitive injection (RI) based on load tests in saturated clay soils on the district of San Sebastian - Cusco, 2016. The study was prepared based on the information provided by companies specialized in soil studies, micropiles and load testing. Eight of fourteen load tests performed in total were analyzed, because they reached failure. In all tests, a manometer was used that measured the force exerted by four hydraulic jacks, as indicated by ASTM D1143. To obtain the last lateral unitary resistance of the bulb (qs), first, the last load was determined, then, at this value, the contribution of lateral load in the non-injected length was subtracted, and that result was divided between the lateral area of contact between the bulb and the surrounding soil. It was determined that the micropiles reached final loads from 39.40 to 101.30 tons, in addition, the contact areas between the bulb and the soil were estimated between 16.51 and 38.46 m2, from this, it was determined that the ultimate lateral unit resistances vary between 1.29 and 3.45 tons per square meter. The purpose of this research is to contribute to the best estimate of the ultimate lateral unitary resistance of the RI-type micropile bulb in saturated clays with SPT number between 10 and 32. / Tesis
2

Uso de Ascophyllum nodosum para o enraizamento de microestacas de eucalipto

Losi, Livia Creste [UNESP] 02 September 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-02Bitstream added on 2014-06-13T20:55:20Z : No. of bitstreams: 1 losi_lc_me_botfca.pdf: 446005 bytes, checksum: 7d7c4bb09f14e32d875db21ebf299ae5 (MD5) / Universidade Estadual Paulista (UNESP) / O presente trabalho teve por objetivo avaliar os efeitos de diferentes doses de extrato de Ascophyllum nodosum na produção de mudas de Eucalytus urograndis e Eucalyptus urophilla durante a fase de enraizamento. Os experimentos foram conduzidos em casa de vegetação, pertencentes às empresas VEC Florestal e Monte Flora, produtoras de microestacas de eucalipto e localizadas na cidade de Bofete, estado de São Paulo. O experimento foi conduzido em quatro fases no período de abril de 2009 a março de 2010, utilizando-se dois clones de E. urograndis (Euca 103 e Euca 105) e um clone de E. urophilla (I144), dois substratos (Brasil Minérios e Carolina Soil) e aplicação de diferentes doses de extrato de A. nodosum (EAN) 0, 0,5, 1, 1,5, 2, 3, 4, 8 e 16 mL L-1. O delineamento experimental adotado foi em blocos ao acaso com 4 repetições e 86 plantas por parcela. As aplicações do extrato de A. nodosum ocorreram aos 0, 7, 14, 21 e 28 dias após o estaqueamento variando conforme a fase. Foram avaliados a massa fresca de raiz (MFR), massa seca de raiz (MSR), comprimento de raiz (CR), massa fresca de parte aérea (MFA), massa seca de parte aérea (MAS), diâmetro do caule (D) e quantidade de raiz (Q) aos 30 e 45 2 dias após dias após o estaqueamento e análise química da planta. As avaliações permitiram observar que houve resposta diferenciada do EAN em relação aos substratos e ao material genético. O tratamento na dose de 3 mL de EAN para o clone I144 proporcionou melhor enraizamento das microestacas. Observou-se também que a forma de aplicação do produto interfere nos resultados / The objective of this work was to evaluate the effects of different rates of extract of Ascophyllum nodosum in the production of microshoots Eucalyptus urograndis and Eucalyptus urophilla during the rooting. The experiments were conducted in a greenhouse belonging to companies VEC Florestal and Monte Flora, two producers of microcuttings eucalyptus and located in the city of Bofete, State of São Paulo. The experiment was conducted in four phases between April 2009 and March 2010, using two clones of E. urograndis (Euca 103 e Euca 105) and one clone of E. urophilla (I144), two substrates (Brasil Minérios and Carolina Soil) and application of different rates of extract A. nodosum (EAN) 0, 0,5, 1, 1,5, 2, 3, 4, 8, 16 mL L-1. The experimental design used was randomized blocks with four replications and 86 plants per plot. The applications of the extract A. nodosum occur at 0, 7, 14, 21 and 28 days after the cutting. It were evaluated root fresh weight (MFR), root dry mass (MSR), root length (CR), fresh weight of shoot (MFA), shoot dry mass (MAS), stem diameter (D) and quality of root (Q) at 30 and 45 days after the cutting. The evaluations allowed to note that there was differential response of EAN in relation to substrates and genetic material, The dose of 3 mL of ean for clone I144 provided better microcuttings rooting. It was also observed that the way of the product application affect the results
3

Uso de Ascophyllum nodosum para o enraizamento de microestacas de eucalipto /

Losi, Livia Creste, 1982- January 2010 (has links)
Orientador: Roberto Lyra Villas Bôas / Banca: Antonio de Pádua Sousa / Banca: Ana Cláudia Pacheco Santos / Resumo: O presente trabalho teve por objetivo avaliar os efeitos de diferentes doses de extrato de Ascophyllum nodosum na produção de mudas de Eucalytus urograndis e Eucalyptus urophilla durante a fase de enraizamento. Os experimentos foram conduzidos em casa de vegetação, pertencentes às empresas VEC Florestal e Monte Flora, produtoras de microestacas de eucalipto e localizadas na cidade de Bofete, estado de São Paulo. O experimento foi conduzido em quatro fases no período de abril de 2009 a março de 2010, utilizando-se dois clones de E. urograndis (Euca 103 e Euca 105) e um clone de E. urophilla (I144), dois substratos (Brasil Minérios e Carolina Soil) e aplicação de diferentes doses de extrato de A. nodosum (EAN) 0, 0,5, 1, 1,5, 2, 3, 4, 8 e 16 mL L-1. O delineamento experimental adotado foi em blocos ao acaso com 4 repetições e 86 plantas por parcela. As aplicações do extrato de A. nodosum ocorreram aos 0, 7, 14, 21 e 28 dias após o estaqueamento variando conforme a fase. Foram avaliados a massa fresca de raiz (MFR), massa seca de raiz (MSR), comprimento de raiz (CR), massa fresca de parte aérea (MFA), massa seca de parte aérea (MAS), diâmetro do caule (D) e quantidade de raiz (Q) aos 30 e 45 2 dias após dias após o estaqueamento e análise química da planta. As avaliações permitiram observar que houve resposta diferenciada do EAN em relação aos substratos e ao material genético. O tratamento na dose de 3 mL de EAN para o clone I144 proporcionou melhor enraizamento das microestacas. Observou-se também que a forma de aplicação do produto interfere nos resultados / Abstract: The objective of this work was to evaluate the effects of different rates of extract of Ascophyllum nodosum in the production of microshoots Eucalyptus urograndis and Eucalyptus urophilla during the rooting. The experiments were conducted in a greenhouse belonging to companies VEC Florestal and Monte Flora, two producers of microcuttings eucalyptus and located in the city of Bofete, State of São Paulo. The experiment was conducted in four phases between April 2009 and March 2010, using two clones of E. urograndis (Euca 103 e Euca 105) and one clone of E. urophilla (I144), two substrates (Brasil Minérios and Carolina Soil) and application of different rates of extract A. nodosum (EAN) 0, 0,5, 1, 1,5, 2, 3, 4, 8, 16 mL L-1. The experimental design used was randomized blocks with four replications and 86 plants per plot. The applications of the extract A. nodosum occur at 0, 7, 14, 21 and 28 days after the cutting. It were evaluated root fresh weight (MFR), root dry mass (MSR), root length (CR), fresh weight of shoot (MFA), shoot dry mass (MAS), stem diameter (D) and quality of root (Q) at 30 and 45 days after the cutting. The evaluations allowed to note that there was differential response of EAN in relation to substrates and genetic material, The dose of 3 mL of ean for clone I144 provided better microcuttings rooting. It was also observed that the way of the product application affect the results / Mestre
4

Gestion de l'eau et dégradation dans les micropiles à combustible planaires / Water management and degradation in planar micro fuel cells

Coz, Erwan 19 September 2016 (has links)
Les micropiles à combustibles sont envisagées pour remplacer ou prolonger l’autonomie des batteries dans les dispositifs nomades. Dans ce domaine, la miniaturisation très poussée a abouti à la réalisation de prototypes planaires multi-cellules d’une puissance de 3 à 5 W. La différence d’architecture par rapport aux piles à combustibles « classiques », l’absence d’auxiliaires de fonctionnement et l’utilisation direct de l’air ambiant comme réactif amènent de nouvelles problématiques au niveau de la gestion de l’eau produite. Le travail de cette thèse porte sur la caractérisation de la gestion de l’eau et l’augmentation de la durée de vie d’un système de micropiles à combustible planaire « à respiration », à température ambiante. L’impact prépondérant de la thermique a été mis en avant, au niveau des points de fonctionnement (noyage aux faibles densités de courant et assèchement aux forts courants) comme au niveau local (gradients entre cellules). Les phénomènes d’assèchement et de noyage ont été étudiés grâce à l’imagerie neutronique. Un des principaux phénomènes observé est la rétrodiffusion d’eau vers l’anode suite une condensation au niveau de la cathode, conduisant à une importante perte de puissance. Une étude de la dégradation lors de fonctionnement longue durée a permis de montrer qu’une mauvaise gestion de l’eau favorise la corrosion d’éléments métalliques, conduisant à une diminution des performances. Une solution visant à éliminer ces phénomènes a été développée et implémentée avec succès. L’intégration du microporeux développé lors de cette thèse a permis d’atteindre une dégradation de 0,1 mV/h sur 2500 h de fonctionnement à 3,5 W. / Micro fuel cells have been considered as potential substitute or complement to batteries for nomad systems, in order to enhance their autonomy. Miniaturization of these objects led to the development of multi-cells planar arrays delivering 3 to 5 W. The specificities of this design compared to the “conventionnal” fuel cell stack architecture, coupled to the removal of peripheral components and the use of ambient air as oxidant, comes along with new challenges concerning water management. This work is focused on the characterization of water management and the lifetime improvement of a planar air-breathing fuel cell array at ambient temperature. Thermal effects have been demonstrated to be of first order concerning the operating conditions (flooding at low current density and drying-out at elevated one) and the local heterogeneities (between cells). Drying-out and flooding have been investigated using neutron imaging. One of the major phenomena observed is back-diffusion linked to water condensation on the cathode side, leading to anodic water accumulation and concomitant power decrease. Investigation of the degradation during long term operation pointed out corrosion of metallic elements as the major issue involved in performance decrease. Development and successful implementation of a solution to counter these troubles led to a limited degradation of 0.1 mV/h during a 2500 h operation at 3.5 W.
5

Analýza stability svahu náchylného k sesouvání / Analysis of slope prone to sliding

Píchová, Sylvie January 2020 (has links)
The diploma thesis illustrates landslide investigation, geophysical and engineering-geological landslide survey and landslide stability reconnaissance. Static calculations based on FEM were performed in the GEO5 program. A back analysis of the landslide mathematical model was executed, which resulted in the reliability of the static landslide assessment. The complicated stabilization construction of the pile and micropile walls were optimized by mathematical modeling of successive phases of construction. The method of execution of construction work during the landslide rehabilitation was designed as well as the dimensions of reinforcing structures.
6

Penzion pro seniory / Pension for Seniors

Vítek, Jan January 2013 (has links)
This Diploma´s thesis proceses topic Pension for Seniors. The object is situated in Božetěchova street in Brno-Královo Pole. This house is new building, three-floored and partial basemented. Basement is a technical floor. On the first floor are spaces of services and offices. On the second and the third floor are situated twenty-eight flats. Shape of the house is „L“ and its basic dimensions are 39,0 x 38,0 meters. The building is finished with a single layered flat roof. Height of house is 10,715 meters. The base structures is of conrete C16/20. The bearing walls on 1S are of monolithic reinforced concrete. Other Bering construction system is used of Porotherm. The staircase structure consists is of monolithic reinforced concrete.
7

Blast-Induced Liquefaction and Downdrag Development on a Micropile Foundation

Lusvardi, Cameron Mark 14 December 2020 (has links)
Frequently, deep foundations extend through potentially liquefiable soils. When liquefaction occurs in cohesionless soils surrounding a deep foundation, the skin-friction in the liquefied layer is compromised. After cyclical forces suspend and pore pressures dissipate, effective stress rebuilds and the liquefied soil consolidates. When the settlement of the soil exceeds the downward movement of the foundation, downdrag develops. To investigate the loss and redevelopment of skin-friction, strain was measured on an instrumented micropile during a blast-induced liquefaction test in Mirabello, Italy. The soil profile where the micropile was installed consisted of clay to a depth of 6m underlain by a medium to dense sand. The 25cm diameter steel reinforced concrete micropile was bored to a depth of 17m. Pore pressure transducers were placed around the pile at various depths to observe excess pore pressure generation and dissipation. Soil strain was monitored with profilometers in a linear arrangement from the center of the 10m diameter ring of buried explosives out to a 12m radius. Immediately following the blast, liquefaction developed between 6m and 12m below ground. The liquefied layer settled 14cm (~2.4% volumetric strain) while the pile toe settled 1.24cm under elastic displacement. The static neutral plane in the pile occurred at a depth of 12m. From 6m to 12m below ground, the incremental skin-friction was 50% compared to pre-liquefaction measurements. The decrease in residual skin-friction is consistent with measurements observed by Dr. Kyle Rollins from previous full-scale tests in Vancouver, BC, Canada, Christchurch, New Zealand, and Turrel, Arkansas.
8

Blast-Induced Liquefaction and Downdrag Development on a Micropile Foundation

Lusvardi, Cameron Mark 14 December 2020 (has links)
Frequently, deep foundations extend through potentially liquefiable soils. When liquefaction occurs in cohesionless soils surrounding a deep foundation, the skin-friction in the liquefied layer is compromised. After cyclical forces suspend and pore pressures dissipate, effective stress rebuilds and the liquefied soil consolidates. When the settlement of the soil exceeds the downward movement of the foundation, downdrag develops. To investigate the loss and redevelopment of skin-friction, strain was measured on an instrumented micropile during a blast-induced liquefaction test in Mirabello, Italy. The soil profile where the micropile was installed consisted of clay to a depth of 6m underlain by a medium to dense sand. The 25cm diameter steel reinforced concrete micropile was bored to a depth of 17m. Pore pressure transducers were placed around the pile at various depths to observe excess pore pressure generation and dissipation. Soil strain was monitored with profilometers in a linear arrangement from the center of the 10m diameter ring of buried explosives out to a 12m radius. Immediately following the blast, liquefaction developed between 6m and 12m below ground. The liquefied layer settled 14cm (~2.4% volumetric strain) while the pile toe settled 1.24cm under elastic displacement. The static neutral plane in the pile occurred at a depth of 12m. From 6m to 12m below ground, the incremental skin-friction was 50% compared to pre-liquefaction measurements. The decrease in residual skin-friction is consistent with measurements observed by Dr. Kyle Rollins from previous full-scale tests in Vancouver, BC, Canada, Christchurch, New Zealand, and Turrel, Arkansas.
9

Catalyseurs électrochimiques pour le stockage et la réduction des oxydes d'azote (NOx) / Electrochemical catalysts for nitrogen oxides storage/reduction

Hadjar, Abdelkader 22 July 2009 (has links)
L’objectif de ce travail était de démontrer la possibilité de coupler sur un même catalyseur, la fonction de stockage et réduction des NOx (sur le baryum) avec un effet électrochimique reposant sur un système micropile. Ce système micropile est composé de nanoparticules catalytiques (Pt et Rh) déposés sur conducteur ionique par les ions O2- (YSZ) en contact avec un support conducteur électronique (SiC dopé) de façon à pouvoir générer, sous mélanges réactionnels, une force électromotrice capable de réduire électrochimiquement une partie des NOx sur le Pt et d’oxyder le CO, les hydrocarbures imbrûlés et H2 sur le Rh. L’effet micropile a été observé sur un catalyseur Pt/Ba (matériau de stockage)/YSZ/Rh enduit dans les canaux d’un filtre à particule en carbure de silicium dopé, en condition essence pauvre à 400°C et en condition Diesel à plus basse température (300°C). Une augmentation de la conversion des NOx d’environ 10% a été observé sur les catalyseurs micropile. L’effet électrochimique a été détecté par une surproduction de CO2, en milieu riche (très peu ou pas de O2) provenant de la réaction d’oxydation électrochimique du CO (produit par vaporeformage) en réagissant avec les ions O2- provenant de YSZ. De plus, des tests catalytiques ont montré que YSZ peut être utilisée comme matériau de stockage des NOx. En effet, un traitement réducteur préalable augmente fortement sa capacité de stockage des NOx / The main objective of this study was to demonstrate the coupling between NOx storage/reduction process on barium, with an electrochemical reduction of NOx (micro fuel cell effect) on the same catalyst. The micro fuel cell effect is ensured by a an electromotive force (potential) which is created between catalytic nanoparticules (Pt and Rh) in contact with an ionic conductor (YSZ) and an electronic conductor (doped SiC). The micro fuel cell effect was observed, during the regeneration phase of the catalysts (rich period), on a Pt/Ba/doped α-SiC-YSZ/Rh monolithic system under lean-burn gasoline conditions at 400°C with an enhancement of about 10 % of the NOx conversion over a complete cycle lean/rich. This electrochemical effect was characterized by the electrochemical oxidation of CO (produced by steam reforming) into CO2 by using O2- ions coming from YSZ. Under Diesel conditions, the micro fuel cell system was found to work at low temperature especially at 300°C. In the second part of the work, a new generation of NOx Storage and reduction catalyst was developed consisting only of noble metals (Pt and/or Rh) deposited on YSZ support (Ba free catalyst). The catalytic measurements revealed that YSZ can be used as a NOx storage material in lean burn conditions (Gasoline and Diesel) especially when it was previously reduced under hydrogen. The storage mechanism would take place on the oxygen vacancies created by the removal of O-2 ions from the YSZ structure
10

Kulturní dům Brno - venkov, stavebně technologická příprava stavby / House of Culture Brno countryside, Civil technical project

Fišer, Jiří January 2017 (has links)
The subject of the master´s is the construction and technological preparation of a house of culture reconstruction. For the construction project it is made a technical report, a estate road layout, a preliminary design of technological implementation, a site equipment, a time and financial schedule, a design of the main building machines and mechanism, technological specifications and test plan. The other topic is a contract of work, a project budget, a comparison of roof production technology and a special topic is a structural analysis of roof girder.

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