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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.
21

Análise de laudos emitidos sobre "prédios tipo caixão" da região metropolitana de Recife : causas apontadas para os desabamentos e interdições

Mauro José Araújo Campelo de Mélo 17 October 2007 (has links)
Nos últimos 20 anos, alguns municípios da Região Metropolitana do Recife - PE, têm sido afetados por problemas diversos em obras de Engenharia Civil, contabilizando, inclusive, óbitos. O mais grave desses problemas, dado ao número de edificações envolvidas, diz respeito aos prédios tipo caixão; alguns ruíram e vários foram e estão interditados e houve desinterdição. O objetivo geral da presente dissertação é analisar os laudos técnicos produzidos sobre os prédios tipo caixão, construídos nos Municípios de Olinda, Jaboatão dos Guararapes e Paulista - PE, tendo como meta estudar as causas apontadas para os desabamentos e interdições das referidas edificações. De um modo geral, pode-se apontar como causas dos desabamentos, as seguintes: falhas ou insuficiência de projeto (31,4%); baixa qualidade ou inadequação dos materiais (17,1%); falhas ou vícios de construção (34,4%); causas ambientais (17,1%). Já para as interdições: falhas ou insuficiência de projeto (21,4%); baixa qualidade ou inadequação dos materiais (3,5%); falhas ou vícios de construção (2,8%); uso inadequado ou falta de manutenção (26,0%); causas ambientais (4,3%); outras causas (42,0%). As desinterdições ocorreram quando foram atendidas as restrições feitas pela Defesa Civil de cada município, e que envolviam problemas estruturais e de habitabilidade. Constata-se também uma atuação inadequada dos órgãos de fiscalização e a ausência de padronização dos laudos e de um modelo técnico para a recuperação adequada dessas construções. Espera-se ter contribuído, através da análise e sistematização dos dados contidos nos laudos estudados, para trabalhos futuros, visando o desenvolvimento de tecnologia capaz de equacionar a situação dos referidos imóveis / In the past 20 years, some cities of the Metropolitan Area of Recife - PE, have been affected by several problems in Civil Engineering constructions, some of which resulted in human deaths. The most serious of these problems, given the number of constructions involved, concerns the specific building called box; some of the buildings did fall and several others have been interdicted. Just a few of them were cleared and the majority of them continue to be interdicted. The general objective of the present dissertation is to analyze the awards produced on the building type box, built in the cities of Olinda, Jaboatão dos Guararapes and Paulista. Its goal is to study the causes pointed out as responsible for the collapse and interdictions of those constructions. In a general way, it can be pointed out as causes of the collapses, the following ones: imperfections or insufficiency of project (31.4%); low quality or inadequacies of the materials (17.1%); construction mistakes (34.4%); environmental causes (17.1%). For the interdictions: imperfections or insufficiencies of project (21.4%); low quality or inadequacies of the materials (3.5%); construction mistakes (2.8%); inadequate use or lack of maintenance (26.0%); environmental causes (4.3%); other causes (42.0%). The buildings were cleared when the conditions made by the Civil Defense of each city were met; they involved structural problems and habitability. Its also evident an inadequate performance of the inspection agencies and the lack of standardization of the awards, as well as the absence of a model for the adequate recovery of these constructions. One expects to have contributed, through the analysis and systematization of the data contained in the studied awards, for future works, aiming at the development of technology capable to equate the situation of the cited real estates.
22

Lembrar para ter o direito de esquecer : a reconstrução historico-sociologica da tragedia da Gameleira em Belo Horizonte e seus reflexos na trajetoria de vida dos atores sociais nela envolvidos / Remembering in order to have the right to forget : the historical-social reconstruction of Gameleira's tragedy in Belo Horizonte na its reflexions in the way of life the social actors involved.

Borba, Antonio Liberio de 24 August 2007 (has links)
Orientador: Olga Rodrigues de Moraes von Simson / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação / Made available in DSpace on 2018-08-09T12:46:11Z (GMT). No. of bitstreams: 1 Borba_AntonioLiberiode_D.pdf: 8868139 bytes, checksum: 9c2d90f97e9c4f5e7d8be5b3e2588f3b (MD5) Previous issue date: 2007 / Resumo: Este estudo tem como objetivo a reconstrução histórico-sociológica da Tragédia da Gameleira (1971) e seus reflexos na memória de Belo Horizonte, sob a ótica dos seus atores sociais. A Tragédia da Gameleira é considerada até hoje o maior acidente na história da construção civil do país e a maior Tragédia ocorrida na cidade de Belo Horizonte. O desabamento do faraônico Pavilhão de Exposição da Gameleira, onde trabalhavam 512 (quinhentos e doze) operários causou a morte de quase uma centena de trabalhadores, um grande número de mutilados e a perda da sanidade mental de vários operários. A obra e sua fiscalização eram do Estado, o projeto de Niemeyer, o cálculo estrutural de Joaquim Cardozo, as fundações executadas pela SOBRAF e a construção da SERGEN Engenharia. A pesquisa seguindo uma abordagem predominantemente qualitativa utilizou a metodologia da História Oral, abrangendo portanto as fontes orais, as fontes documentais imagética, jornalística e jurídica. Constituiu-se assim, a base para a construção das 13 (treze) categorias de análise que subsidiaram a reconstrução históricosociológica da Tragédia da Gameleira. A amostra foi composta por 6 (seis) grupos perfazendo um total de 26 (vinte e seis) depoentes. A pesquisa alcançou o seu objetivo ao elaborar a reconstrução histórico-sociológica da Tragédia da Gameleira sob a ótica de seus atores sociais. O Trabalho contribuiu para a elucidação e a compreensão da Tragédia e seus reflexos na trajetória de vida dos atores sociais nela envolvidos. Em conseqüência há um empoderamento, em curso, dos atores sociais a exemplo da necessidade demandada pelos mesmos da construção de um Memorial às vítimas da Tragédia da Gameleira / Abstract: This study has its objective the social-historical construction of the Gameleira Tragedy (1971) and its consequences in the memory off Belo Horizonte from the perspective of its social players. The Gameleira Tragedy is considered even today the biggest accident in the history of the construction industry in the country and the biggest ever to occur in the city of Belo Horizonte. The collapse of the colossal Gameleira Expo Pavilion where 512 laborers worked caused the death of almost a hundred workers, a large number of people were maimed and others had mental problems. The construction and inspection responsibilities rested on the shoulder of the state, the project was Niemeyer?s, the structural calculations were the responsibility of Joaquim Cardozo, the foundation was executed by SOBRAF and the building was the responsibility of SERGEN Engineering. The research follows mainly a qualitative approach utilizing the Oral History methodology encompassing therefore oral sources documents, legal and journalistic imagery. This is thus, the bases for a construction for 13 categories of analysis that subsidized the social-historical reconstruction of the Gameleira Tragedy. The sample was composed of 6 groups for a total of 26 deponents. The research achieved its objective by elaborating a social-historic reconstruction of the Gameleira Tragedy from the perspective of its social actors. The work contributes to the elucidation and understanding of the Tragedy and its consequences on the way of life of the social actors envolved in it. As a consequence there is an empowerment in course of the social players in view of the need required by them for the construction of a Memorial to honor the victims of the Gameleira Tragedy / Doutorado / Educação, Sociedade, Politica e Cultura / Doutor em Educação
23

Análise de laudos emitidos sobre "prédios tipo caixão" da região metropolitana de Recife : causas apontadas para os desabamentos e interdições

Mélo, Mauro José Araújo Campelo de 17 October 2007 (has links)
Made available in DSpace on 2017-06-01T17:57:23Z (GMT). No. of bitstreams: 1 Mauro Melo_Dissert.pdf: 1426265 bytes, checksum: 0a54c25d1117b83eb91a5131e2fc6841 (MD5) Previous issue date: 2007-10-17 / In the past 20 years, some cities of the Metropolitan Area of Recife - PE, have been affected by several problems in Civil Engineering constructions, some of which resulted in human deaths. The most serious of these problems, given the number of constructions involved, concerns the specific building called box ; some of the buildings did fall and several others have been interdicted. Just a few of them were cleared and the majority of them continue to be interdicted. The general objective of the present dissertation is to analyze the awards produced on the building type box , built in the cities of Olinda, Jaboatão dos Guararapes and Paulista. Its goal is to study the causes pointed out as responsible for the collapse and interdictions of those constructions. In a general way, it can be pointed out as causes of the collapses, the following ones: imperfections or insufficiency of project (31.4%); low quality or inadequacies of the materials (17.1%); construction mistakes (34.4%); environmental causes (17.1%). For the interdictions: imperfections or insufficiencies of project (21.4%); low quality or inadequacies of the materials (3.5%); construction mistakes (2.8%); inadequate use or lack of maintenance (26.0%); environmental causes (4.3%); other causes (42.0%). The buildings were cleared when the conditions made by the Civil Defense of each city were met; they involved structural problems and habitability. It s also evident an inadequate performance of the inspection agencies and the lack of standardization of the awards, as well as the absence of a model for the adequate recovery of these constructions. One expects to have contributed, through the analysis and systematization of the data contained in the studied awards, for future works, aiming at the development of technology capable to equate the situation of the cited real estates. / Nos últimos 20 anos, alguns municípios da Região Metropolitana do Recife - PE, têm sido afetados por problemas diversos em obras de Engenharia Civil, contabilizando, inclusive, óbitos. O mais grave desses problemas, dado ao número de edificações envolvidas, diz respeito aos prédios tipo caixão ; alguns ruíram e vários foram e estão interditados e houve desinterdição. O objetivo geral da presente dissertação é analisar os laudos técnicos produzidos sobre os prédios tipo caixão , construídos nos Municípios de Olinda, Jaboatão dos Guararapes e Paulista - PE, tendo como meta estudar as causas apontadas para os desabamentos e interdições das referidas edificações. De um modo geral, pode-se apontar como causas dos desabamentos, as seguintes: falhas ou insuficiência de projeto (31,4%); baixa qualidade ou inadequação dos materiais (17,1%); falhas ou vícios de construção (34,4%); causas ambientais (17,1%). Já para as interdições: falhas ou insuficiência de projeto (21,4%); baixa qualidade ou inadequação dos materiais (3,5%); falhas ou vícios de construção (2,8%); uso inadequado ou falta de manutenção (26,0%); causas ambientais (4,3%); outras causas (42,0%). As desinterdições ocorreram quando foram atendidas as restrições feitas pela Defesa Civil de cada município, e que envolviam problemas estruturais e de habitabilidade. Constata-se também uma atuação inadequada dos órgãos de fiscalização e a ausência de padronização dos laudos e de um modelo técnico para a recuperação adequada dessas construções. Espera-se ter contribuído, através da análise e sistematização dos dados contidos nos laudos estudados, para trabalhos futuros, visando o desenvolvimento de tecnologia capaz de equacionar a situação dos referidos imóveis
24

Avaliação do grau do dano das estruturas do subsolo de três edifícios situados na Região Metropolitana do Recife / Evaluation of the degree of damage in the subsoil structures of three buildings situated in the Region Metropolitan of Recife/PE

Lemos, Sérgio Pereira Pinto 20 April 2006 (has links)
Made available in DSpace on 2017-06-01T17:57:27Z (GMT). No. of bitstreams: 1 pre-textual.pdf: 28868 bytes, checksum: 1349eefd05bbc7c21b1dd3b9e4b92ecb (MD5) Previous issue date: 2006-04-20 / This work aims to evaluate the pathology of residential buildings structures located at the Metropolitan Region of Recife, Brazil using the quantification of damages to measure the degree of early deterioration of reinforced concrete. Three residential buildings (RB) with similar construction standards were studied. All buildings have approximate age and are inserted into environmental aggressiveness distinct. A visual inspection took place as well as a laboratorial sample analysis of their pillars, beams and underground water reservatories. It was verified that the RB1 case, located at a high environmental aggressiveness class (III), and the RB2 case, located significatively far from the sea and classified with a moderate environmental aggressiveness class (II), both presented a medium degree of deterioration (GDE). For both buildings it is suggested a periodic inspection recommendation and a medium term intervention (GD 1 = 36,98 ; GD 2 = 31,23). The third case (RB3), located at a high environmental aggressiveness class (III) and seafront with protection barriers, presented a high degree of deterioration (GD 3=103,94). It is suggested for RB3 an immediate intervention with collapse risks / Procurando conhecer o grau de deterioração precoce das estruturas de concreto armado dos edifícios residenciais da Região Metropolitana da Cidade do Recife, Estado de Pernambuco, este trabalho visa, utilizando um método de quantificação dos danos e o uso de ensaios, avaliar as patologias das estruturas estudadas. Estudou-se três edifícios residenciais (ER), com semelhante padrão de construção, idades construtivas aproximadas e inseridos em diferentes classes de agressividade ambiental. Foi realizada inspeção visual e ensaios em amostras dos pilares, vigas, lajes e reservatório inferior do subsolo dos três edifícios. Após análise dos três edifícios, verificou-se que o caso ER 1, localizado em classe ambiental de agressividade forte (III), a mais agredida pelo meio ambiente, e o estudo de caso ER 2, localizado a uma distância significativa da orla marinha em Classe de Agressividade Ambiental II, apresentaram grau de deterioração media (GD) de 36,98 e 31,23 respectivamente, com recomendação para inspeção periódica e intervenção a médio prazo. Já o estudo de caso ER 3, que está localizado dentro da uma classe de agressividade forte (III), em orla marinha, porém com barreiras de proteção que evitam a incidência direta da névoa salina, encontra-se com alto grau de deterioração (GD = 103,94), sugerindo uma intervenção imediata com riscos de colapso
25

Progressive collapse simulation of reinforced concrete structures: influence of design and material parameters and investigation of the strain rate effects

Santafe Iribarren, Berta 17 June 2011 (has links)
This doctoral research work focuses on the simulation of progressive collapse of reinforced concrete structures. It aims at contributing to the ‘alternate load path’ design approach suggested by the General Services Administration (GSA) and the Department of Defense (DoD) of the United States, by providing a detailed yet flexible numerical modelling tool. <p><p>The finite element formulation adopted here is based on a multilevel approach where the response at the structural level is naturally deduced from the behaviour of the constituents (concrete and steel) at the material level. One-dimensional nonlinear constitutive laws are used to model the material response of concrete and steel. These constitutive equations are introduced in a layered beam approach, where the cross-sections of the structural members are discretised through a finite number of layers. This modelling strategy allows deriving physically motivated relationships between generalised stresses and strains at the sectional level. Additionally, a gradual sectional strength degradation can be obtained as a consequence of the progressive failure of the constitutive layers. This means that complex nonlinear sectional responses exhibiting softening can be obtained even for simplified one dimensional constitutive laws for the constituents.<p><p>This numerical formulation is used in dynamic progressive collapse simulations to study the structural response of a multi-storey planar frame subject to a sudden column loss. The versatility of the proposed methodology allows assessing the influence of the main material and design parameters in the structural failure. Furthermore, the effect of particular modelling options of the progressive collapse simulation technique, such as the column removal time or the strategy adopted for the structural verification, can be evaluated.<p><p>The potential strain rate effects on the structural response of reinforced concrete frames are also investigated. To this end, a strain rate dependent material formulation is developed, where the rate effects are introduced in both the concrete and steel constitutive response. These effects are incorporated at the structural level through the multilayered beam approach. In order to assess the degree of rate dependence in progressive collapse, the results of rate dependent simulations are presented and compared to those obtained via the rate independent approach. The influence of certain parameters on the rate dependent structural failure is also studied.<p><p>The differences obtained in terms of progressive failure degree for the considered parametric variations and modelling options are analysed and discussed. The parameters observed to have a major influence on the structural response in a progressive collapse scenario are the ductility of the steel bars, the degree of symmetry and/or continuity of the reinforcement and the column removal time. The results also depend on the strategy considered (GSA vs DoD). The strain rate effects are confirmed to play a significant role in the failure pattern. Based on these observations, general recommendations for the design of progressive collapse resisting structures are finally derived.<p><p><p><p><p>L’effondrement progressif est un sujet de recherche qui a connu un grand développement suite aux événements désastreux qui se sont produits au cours des dernières décennies. Ce phénomène est déclenché par la défaillance soudaine d’un nombre réduit d’éléments porteurs de la structure, qui provoque une propagation en cascade de l’endommagement d’élément en élément jusqu’à affecter une partie importante, voire la totalité de l’ouvrage. Le résultat est donc disproportionné par rapport à la cause. La plupart des codes de construction ont inclus des prescriptions pour le dimensionnement des structures face aux actions accidentelles. Malheureusement, ces procédures se limitent à fournir des ‘règles de bonne pratique’, ou proposent des calculs simplifiés se caractérisant par un manque de détail pour permettre leur mise en oeuvre.<p><p>Cette thèse de doctorat intitulée Simulation de l’Effondrement Progressif des Structures en Béton Armé: Influence des Paramètres Materiaux et de Dimensionnement et Investigation des Effets de Vitesse a pour but de contribuer à la simulation numérique de l’effondrement progressif des structures en béton armé. Une formulation aux éléments finis basée sur une approche multi-échelles a été développée, où la réponse à l’échelle structurale est déduite à partir de la réponse au niveau matériel des constituants (le béton et l’acier). Les sections des éléments structuraux sont divisées en un nombre fini de couches pour lesquelles des lois constitutives unidimensionnelles sont postulées. Cet outil permet une dégradation graduelle de la résistance des sections en béton armé suite à la rupture progressive des couches. Des comportements complexes au niveau des points de Gauss peuvent être ainsi obtenus, et cela même à partir de lois unidimensionnelles pour les constituants.<p><p>Cette formulation est utilisée pour la simulation de l’effondrement progressif d’ossatures 2D, avec prise en compte des effets dynamiques. La versatilité de la présente stratégie numérique permet d’analyser l’influence de différents paramètres matériaux et de dimensionnement, ainsi que d’autres paramètres de modélisation, sur la réponse structurale face à la disparition soudaine d’une colonne.<p><p>Les effets de la vitesse de déformation sur le comportement des matériaux constituants est aussi un sujet d’attention dans ce travail de recherche. Des lois constitutives prenant en compte ces effets sont postulées et incorporées au niveau structural grâce à l’approche multi-couches. Le but est d’étudier l’influence des effets de la vitesse de chargement sur la réponse structurale face à la disparition d’un élément porteur. Les resultats obtenus à l’aide de cette approche avec effets de vitesse sont comparés à ceux obtenus avec des lois indépendantes de la vitesse.<p><p>Les différences dans la réponse à la disparition d’une colonne sont analysées pour les variations paramétriques étudiées. Les paramètres ayant une influence importante sont notamment: la ductilité des matériaux constituants et la disposition et/ou la symétrie des armatures. Les effets de vitesse sont également significatifs. Sur base de ces résultats, des recommandations sont proposées pour le dimensionnement et/ou l’analyse des structures face à l’effondrement progressif.<p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

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