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11	Modélisation géomécanique et probabiliste des rideaux de palplanches : prise en compte de l’interaction sol-structure et de la variabilité spatiale du sol / Geomechanical and probabilistic modelling of sheet pile walls : soil-structure interaction and soil spatial variability effects Mokeddem, Abdelhammid 02 May 2018 (has links) Le comportement géomécanique des ouvrages géotechniques à l’exemple des rideaux de palplanches est entaché d’incertitudes épistémiques liées aux hypothèses régissant le modèle géomécanique de calcul, mais aussi d’incertitudes aléatoires liées à la variabilité spatiale du sol. L’objectif principal de cette thèse est de mieux appréhender l’effet de ces incertitudes sur le comportement d’un rideau de palplanches. Pour cela le présent mémoire s’articule autour de quatre points principaux : Le premier point est relatif d’une part à l’analyse des hypothèses utilisées pour la modélisation géomécanique d’un rideau de palplanches et d’autre part à l’extension de la méthode des coefficients de réaction d’un système unidimensionnel basé sur une poutre et des appuis élastoplastiques à un système bidimensionnel de plaque orthotrope sur le même type d’appuis (MISS-CR-PLQ). Le deuxième point concerne la modélisation de la variabilité spatiale du sol. Après une comparaison entre deux méthodes de génération de champs aléatoires nous avons retenu la méthode Circulant Embedding pour son efficience. Plusieurs études paramétriques ont été menées pour analyser les effets des hypothèses prises lors de la génération des champs aléatoires. Le troisième point concerne la mise en place d’une démarche mécano-fiabiliste permettant d’intégrer la variabilité spatiale du sol pour le cas des rideaux de palplanches. Le quatrième point est consacré à l’application de la démarche développée pour un cas d’étude à travers des analyses probabilistes et fiabilistes. L’influence des paramètres statistiques (e.g. les longueurs de corrélations, la corrélation croisée, …), mécanique et géométrique a été étudiée. / The geomechanical behaviour of geotechnical structures such as sheet pile walls is subjected to epistemic uncertainties due to geomechanical models’ assumptions and also the aleatory uncertainties which could be related to the soil spatial variability. The main objective of this thesis is to gain more insight into the effect of these uncertainties on the sheet pile behaviour. To this end, this thesis focuses on four main issues: The first one is related on the one hand to the analysis of the used geomechanical hypotheses for modelling of retaining walls. On the other hand, to extend the one-dimensional subgrade reaction method which is based on a beam relying on elastoplastic supports to a two-dimensional system that call to an orthotropic plate relying on the same supports (MISS-CR-PLQ). The second issue concerns the soil spatial variability modelling. After a key comparison between two random field generation methods, we selected the Circulating Embedding method for its efficiency. Several parametric studies have been conducted to analyse the effects of different assumptions of random field generation. The third issue is related to the implementation of the proposed mechanical-reliability approach taking into account the soil spatial variability. The last issue is devoted to the application of the developed approach to a case study through probabilistic and reliability analyses. The influence of statistical parameters (e.g. correlation lengths, cross-correlation,...), mechanical and geometrical has been examined. Rideau de palplanches Fiabilité Démarche mécano-fiabiliste Variabilité spatiale Comportement orthotrope MISS-CR-PLQ Coefficients de réaction Interaction sol-structure Sheet pile walls Reliability Mechanical reliability approach Spatial variability Orthotropic behaviour MISS-CR-PLQ Subgrade reaction Soil-structure interaction
12	Monitoramento de uma estrutura de contenção em estacas espaçadas considerando perfil de sucção / Monitoring of sheet pile wall considering a suction profile Gomes, Adriana Cristina 14 August 2015 (has links) Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-03-31T20:10:43Z No. of bitstreams: 2 Dissertação - Adriana Cristina Gomes - 2015.pdf: 14045273 bytes, checksum: 9bf9ee1429dd1afc11c6d19ff58a65c7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-04T11:48:47Z (GMT) No. of bitstreams: 2 Dissertação - Adriana Cristina Gomes - 2015.pdf: 14045273 bytes, checksum: 9bf9ee1429dd1afc11c6d19ff58a65c7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-04-04T11:48:47Z (GMT). No. of bitstreams: 2 Dissertação - Adriana Cristina Gomes - 2015.pdf: 14045273 bytes, checksum: 9bf9ee1429dd1afc11c6d19ff58a65c7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-08-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study presents the results of an extensive field monitoring program in which the lateral displacements of a nail reinforced sheet pile wall in Goiânia, Brazil were measured during the excavation process. The instrumentation methods adopted were multiple point borehole extensometers (MPBX) and optical surveying. The MPBX showed good results that could be appropriately interpreted as the excavation progressed. However, the measurements of optical surveying were not reliable due the low precision of total station and for being highly affected by user’s errors. In order to determine the geotechnical profile, laboratory test were undertaken to obtain strength and deformation parameters for unsaturated and saturated soil conditions. The large variability of the soil, observed in terms of void ratio, presented an important obstacle, making the determination of representative shear strength parameters a challenge. As a way to bridge the analysis of field monitoring results, soil properties and the numerical back analyses of the retaining walls, the water content profile and the soil-water characteristic curve were measured. Such data was used to obtain the suction profile and evaluated its influence in the monitored field data. Finally, the numerical code Sheeting Check (Geo5), which uses the beam on elastic foundation method, was employed to obtain the soil subgrade reaction modulus (ks) and determine the retaining wall deformation profile and earth pressures in saturated and unsaturated soil condition. The maximum lateral displacements values found in the numerical back analyses were compatible with the monitoring results. Besides, the influence of unsaturated soil conditions and soil suction in the reduction of the retaining wall deformations and the active earth pressures were observed. / Este estudo apresenta resultados de um extenso monitoramento de deslocamentos horizontais de uma estrutura de contenção em estacas espaçadas com tirantes passivos na cidade de Goiânia, Brasil que foram medidas durante o processo de escavação. Os métodos de instrumentação adotados foram de extensômetros de hastes horizontais múltiplas (EHHM) e medições topográficas. O EHHM apresentou bons resultados que permitiu interpretar corretamente o progresso da escavação. Todavia, as medições topográficas não foram confiáveis devido à baixa precisão da Estação Total e sendo bastante afetados por erros do usuário. Para determinar o perfil geotécnico do solo, ensaios em laboratório foram realizados para obter parâmetros de resistência e deformabilidade para o solo na condição natural e saturada. A grande variabilidade do solo, observada em termos de índice de vazios, se apresenta como importante obstáculo, tornando a determinação representativa dos parâmetros de resistência ao cisalhamento um desafio. Buscando acoplar as análises dos resultados de monitoramento em campo, propriedades do solo e retro análises da estrutura de contenção, o perfil de umidade e a curva característica solo-água foram medidos. Esses dados foram utilizados para obter o perfil de sucção do solo e avaliar sua influência nos dados monitorados em campo. Por fim, a ferramenta numérica Shetting Check (Geo5), que aplica o método de viga apoiada sobre base elástica, foi utilizada para obter o módulo de reação do solo (ks) e avaliar o comportamento do perfil de deformação da parede de contenção e do empuxo de terra para o solo na condição saturada e não saturado. Os valores de deslocamentos horizontais máximos obtidos a partir da retro análise apresentam-se compatíveis com valores da literatura. Além disso, a influência da sucção na redução da deformação da parede de contenção e dos empuxos ativos foi observada. Monitoramento Estruturas de contenção Solos não saturados Método da viga sobre apoio elástico Módulo de reação do solo Monitoring Retaining wall Unsaturated soils Beam on elastic foundation method Subgrade reaction of soil ENGENHARIA CIVIL::GEOTECNICA
13	Návrh zajištění stavební jámy hloubeného úseku tunelu na vysokorychlostní trati Brno-Přerov / Design of sheeting on a excavated section of tunnel on a high-speed line Brno-Přerov Umlauf, Jiří January 2020 (has links) In first part of the thesis are proposed four variants of retaining structures for deep excavation of cut-and-cover tunnel part. It is nailed slope, pile wall, nailed slope in combination with pile wall and soldier pile wall. For those structures is in following part carried out an economic analysis and the most cost effective variant is chosen. Chosen structure is further analyzed in next part. This analysis is carried out with finite element method in software PLAXIS. As a material model is chosen Hardening Soil model and input parameters were determined by empiric formulas from literature. Behavior of neogene clays, in which is the structure designed, is considered as undrained, by type Undrained A. In the last part of the thesis is described technological procedure of construction this retaining structure.
14	Effets des incertitudes et de la variabilité spatiale des propriétés des sols et des structures sur le dimensionnement des semelles filantes et des conduites enterrées / Effects of uncertainties and spatial variation of soil and structure properties on geotechnical design : cases of continuous spread footings and buried pipes Imanzadeh, Saber 15 February 2013 (has links) Le sol présente une variabilité spatiale des propriétés physiques et mécaniques dont les effets sur des structures légères avec semelles filantes et sur les conduites enterrées ne sont pas bien pris en compte dans leur dimensionnement. Cette variabilité naturelle peut être très importante dans le cas de ces ouvrages car elle induit des tassements différentiels, dont les conséquences peuvent être dommageables : fissures dans les murs, les poutres ou encore des fuites dans les réseaux d’assainissement. La variabilité naturelle du sol et l'incertitude liée à la connaissance imparfaite des propriétés du sol et/ou du béton ou de l'acier de la structure sont les principales sources d'incertitude dans le choix des paramètres de calcul pour le dimensionnement de ces structures. Dans cette thèse, une approche analytique avec les méthodes probabilistes (FOSM et SOSM) et le modèle de Winkler, puis numérique avec le couplage de la méthode des éléments finis avec des approches géostatistiques ont été successivement menées pour modéliser le comportement des semelles filantes et des conduites enterrés lorsque les incertitudes sur les propriétés mécaniques du sol et de la structure sont prises en compte dans leur dimensionnement. Il apparait ainsi, l’importance du comportement longitudinal de ces ouvrages et du poids des incertitudes dans leur dimensionnement. / Soil exhibits spatial heterogeneities resulting from the history of its deposition and aggregation processes that occur in different physical and chemical environments. This inherent or natural variability can be very important in the case of the superficial geotechnical works inducing differential settlements, whose consequences on structural response can be harmful: local failures, cracking in beams or walls, leakage in sewers. Natural variability of soil and uncertainty related to imperfect knowledge in soil properties and/or of concrete or steel of the structure, are the major source of uncertainty in the choice of the design parameters. In this thesis the probabilistic methods in geotechnical engineering, the analytical Winkler model and the coupling of the finite element method with geostatistical approaches were successively used to model the behavior of shallow foundations and buried pipe networks when soil and structure uncertainties are considered in their design. Incertitude Variabilité spatiale Module de réaction du sol Semelle filante Conduite enterrée Interaction sol-structure Approches analytique et numérique Géostatistique Uncertainty Spatial variability Subgrade reaction modulus Spread footing Buried pipe Soil-structure interaction Analytical and numerical methods Geostatistic 关键词误差空间变化土质反应模块条形地基地下管道土地-结构的相互作用分析方法与数字方法地质统计 Incertidumbre Variabilidad espacial Módulo de reacción del suelo Cimientos continuos (zapatas) Tubería enterrada (canalización) Interacción suelo – estructura Modelos analíticos y numéricos Geoestadística Incertitudine Variabilitate spațială Modul de reacție Conducta îngropată Interactiune sol-structura Modele analitice și numerice Geostatistică Belirsizlik Mekansal değişkenlik Yer reaksiyonu modülü Şerit temeller Gömülü boru Zemin-yapı etkileşimi Analitik ve sayısal yaklaşımlar Jeoistatistik Неопределенность Закопанные трубы Геостатистика Incertezza Variabilità spaziale Modulo di reazione del calore del sole Soletta conduttiva Condotta interrata Interazione delle strutture del suolo Approccio analitico e numerico Geostatico مبدأ الريبة التغير المكاني الأساسات المنفصلة الانابيب المطمورة الاحصاءات الجغرافية عدم قطعیت تغييرپذيري فضايي مدول واکنش بستر سطحي فونداسيون لوله هاي مدفون اثر متقابل سازه و خاک روشهای عددي و تحليلي

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