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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.
81

Multi-lead ST-monitoring in the early assessment of patients with suspected or confirmed unstable coronary artery disease

Jernberg, Tomas January 2000 (has links)
<p>This study evaluated the use of multi-lead ST-monitoring in the early assessment of patients with suspected or confirmed unstable coronary artery disease (UCAD).</p><p>At continuous 12-lead ECG (c12ECG), the definition of an ischemic episode as a transient ST-deviation ¡Ý0 for at least 1 minute resulted in a good observer agreement (kappa=0.72) and an acceptable incidence of postural ST-changes.</p><p>When c12ECG was performed from admission and for 12 hours in 630 patients with suspected UCAD, 16% had ischemic episodes. At 30 days, patients with episodes had a higher risk of cardiac death or myocardial infarction (MI) (10% vs. 1.5%). In a multivariate analysis, troponin T¡Ý0.10¦Ìg/l and presence of ischemic episodes were independent predictors of cardiac death or MI. When ST-monitoring and troponin T status were combined, patients could be divided into a low-, intermediate-, and high-risk group with 1%, 4% and 12% risk for cardiac death or MI at 30 days of follow up.</p><p>As a part of a multicenter trial, including patients with UCAD, 1016 patients underwent ST-monitoring with c12ECG or continuous vectorcardiography (cVCG). Ischemia was detected in 32% and 35%, respectively. When the groups with ischemia were compared, the groups were similar with respect to several clinical variables. Thus, these methods identify the same high-risk population.</p><p>Of the 629 patients treated non-invasively with extended treatment of low-molecular- weight heparin (LMWH) or placebo, 34% had ischemic episodes. In this group at 3 months, patients administered LMWH had a significantly lower risk of death, MI, or revascularization than patients treated with placebo (35.2% vs. 53.4%). In patients without transient ischemic episodes, the outcome in the LMWH and placebo group was similar.</p><p>Thus, multi-lead monitoring provides important prognostic information early after admission in this population, and seems to identify patients who benefit most from extended antithrombotic treatment.</p>
82

Multi-lead ST-monitoring in the early assessment of patients with suspected or confirmed unstable coronary artery disease

Jernberg, Tomas January 2000 (has links)
This study evaluated the use of multi-lead ST-monitoring in the early assessment of patients with suspected or confirmed unstable coronary artery disease (UCAD). At continuous 12-lead ECG (c12ECG), the definition of an ischemic episode as a transient ST-deviation ¡Ý0 for at least 1 minute resulted in a good observer agreement (kappa=0.72) and an acceptable incidence of postural ST-changes. When c12ECG was performed from admission and for 12 hours in 630 patients with suspected UCAD, 16% had ischemic episodes. At 30 days, patients with episodes had a higher risk of cardiac death or myocardial infarction (MI) (10% vs. 1.5%). In a multivariate analysis, troponin T¡Ý0.10¦Ìg/l and presence of ischemic episodes were independent predictors of cardiac death or MI. When ST-monitoring and troponin T status were combined, patients could be divided into a low-, intermediate-, and high-risk group with 1%, 4% and 12% risk for cardiac death or MI at 30 days of follow up. As a part of a multicenter trial, including patients with UCAD, 1016 patients underwent ST-monitoring with c12ECG or continuous vectorcardiography (cVCG). Ischemia was detected in 32% and 35%, respectively. When the groups with ischemia were compared, the groups were similar with respect to several clinical variables. Thus, these methods identify the same high-risk population. Of the 629 patients treated non-invasively with extended treatment of low-molecular- weight heparin (LMWH) or placebo, 34% had ischemic episodes. In this group at 3 months, patients administered LMWH had a significantly lower risk of death, MI, or revascularization than patients treated with placebo (35.2% vs. 53.4%). In patients without transient ischemic episodes, the outcome in the LMWH and placebo group was similar. Thus, multi-lead monitoring provides important prognostic information early after admission in this population, and seems to identify patients who benefit most from extended antithrombotic treatment.
83

Early Invasive Strategy in Unstable Coronary Artery Disease : Outcome in Relation to Risk Stratification

Diderholm, Erik January 2002 (has links)
In unstable coronary artery disease (CAD) it still is a matter of debate which patients should undergo early revascularisation. In the FRISC II study (n=2457) an early invasive strategy was, compared to a primarily non-invasive strategy, associated with reduced mortality and myocardial infarction (MI) rates. However, in this heterogeneous group of patients, tools for an appropriate selection to revascularisation are needed. From the FRISC II study we evaluated the prognosis, the angiographic extent of CAD and the effects of an early invasive strategy in relation to risk variables on admission. The occurrence of ST depression and/or elevated levels of Troponin T were associated with a higher risk for death and MI, more severe CAD and also with a reduction of death or MI by the early invasive strategy. Elevated levels of the inflammatory markers C-reactive protein (CRP) and interleukin-6 (Il-6) were associated with a higher mortality but an unchanged MI rate. Elevated levels of Il-6, but not CRP, identified patients with a large reduction of mortality by the invasive strategy. Age ≥ 70 years, male gender, diabetes, previous MI, ST depression and elevated levels of troponin and markers of inflammation were independently associated with an adverse outcome. The FRISC-score was constructed using these 7 variables. At FRISC-score ≥ 5 an early invasive strategy markedly reduced mortality and MI, at FRISC–score 3-4 death/MI was reduced, whereas in patients with a FRISC-score 0-2 neither mortality nor death/MI was influenced. In unstable CAD, a non-invasive strategy seems justified only for patients at low risk, i.e. FRISC score &lt; 2. In patients with intermediate and high risk, i.e. FRISC-score ≥ 3, an early invasive strategy is recommended.
84

A numerical case study about bifurcations of a local attractor in a simple capsizing model

Julitz, David 07 October 2005 (has links) (PDF)
In this article we investigate a pitchfork bifurcation of the local attractor of a simple capsizing model proposed by Thompson. Although this is a very simple system it has a very complicate dynamic. We try to reveal some properties of this dynamic with modern numerical methods. For this reason we approximate stable and unstable manifolds which connect the steady states to obtain a complete understanding of the topology in the phase space. We also consider approximations of the Lyapunov Exponents (resp. Floquet Exponents) which indicates the pitchfork bifurcation.
85

Pratimų su terapiniais kamuoliais poveikis 16-18 metų moksleivių liemens raumenų ištvermei / Effect for 16-18 years old students waist muscular stamina from exercises with therapeutic balls

Jacinavičiūtė, Kamilė 06 September 2013 (has links)
Tyrimo objektas: 16- 18 metų merginų liemens raumenų ištvermė ir pratimų su terapiniais kamuoliais poveikis jai. Pratimai ant nestabilių paviršių yra efektyvesni nei pratimai, ant stabilaus paviršiaus, siekiant liemens raumenų ištvermės gerinimo (Hodges et al., 1996; Anderson&Behm, 2005). Susitiprėjus liemens raumenų ištvermei, gerėja laikysena (Dudonienė ir Radzevičiūtė, 2010). Iškelta hipotezė, kad sistemingas pratimų su terapiniais kamuoliais (ant nestabilaus paviršiaus) integravimas į popamokinės, sportinės veiklos užsiėmimus, mokyklinio amžiaus merginoms, turės teigiamą poveikį jų liemens raumenų ištvermei. Darbo tikslas: nustatyti pratimų su terapiniais kamuoliais (ant nestabilaus paviršiaus) poveikį 16-18 metų merginų liemens raumenų ištvermei. Darbo uždaviniai: 1. Nustatyti ir palyginti 16-18 metų merginų liemens raumenų ištvermę, prieš pradedant mankštas su terapiniais kamuoliais (ant nestabilaus paviršiaus) ir merginų, kurios atliks pratimus ant stabilių paviršių. 2. Nustatyti ir palyginti 16-18 metų merginų liemens raumenų ištvermę, po 4 sav. trukusių mankštų su terapiniais kamuoliais (ant nestabilaus paviršiaus) ir merginų, atlikusių pratimus ant stabilių paviršių. 3. Nustatyti ir palyginti 4 sav. trukusių mankštų su terapiniais kamuoliais (ant nestabilaus paviršiaus) ir mankštų ant stabilaus paviršiaus poveikį 16-18 metų merginų liemens raumenų ištvermei. Darbo rezultatai: Po 4 sav. trukusios pratimų programos su kamuoliais (ant nestabilaus... [toliau žr. visą tekstą] / Object of research: Stamina of 16-18 years old girls waist muscle and effect with therapeutic balls for it. Exercises on unstable surfaces are more effective than those on stable surface, seeking for improvement of muscular waist stamina (Hodges et al., 1996; Anderson & Behm, 2005). When stamina of waist muscle is increased, posture also improves (Dudoniene and Radzeviciute, 2010). Hypothesis is held, that systematic integration of exercises with therapeutic balls (on unstable surface) into after-school sports activity of school age girls, will take a positive effect for the stamina of their waist muscle. Purpose of work: to determine the effect of exercises with therapeutic balls (on unstable surface) for 16-18 years old girls waist muscle stamina. Goals of work: 1. To determine and compare the stamina between 16-18 years old girls waist muscle before starting the exercises with therapeutic balls (on unstable surface) and girls, which will do exercises on stable surfaces. 2. To determine and compare the stamina between 16-18 years old girls waist muscle after 4 weeks of exercises with therapeutic balls (on unstable surface) and girls, which have done exercises on stable surfaces. 3. To determine and compare the effect of 4 weeks of exercises with therapeutic balls (on unstable surface) and exercises on stable surface for stamina of 16-18 years old girls waist muscle. Results of work: After 4 weeks exercise program with balls (on unstable surface) statistically... [to full text]
86

Modélisation des effets d'interpénétration entre fluides au travers d'une interface instable

Huber, Grégory 28 August 2012 (has links)
Les mélanges multiphasiques en déséquilibre de vitesse sont habituellement modélisés à l'aide d'un modèle à 6 ou 7 équations (Baer and Nunziato, 1986). Ces modèles sont très efficaces pour traiter des mélanges avec effets d'interpénétration. Ils peuvent aussi être utilisés pour traiter des problèmes à interface dans lesquels il est nécessaire de respecter les conditions d'interface (continuité de la vitesse normale et de la pression). Ceci est réalisé à l'aide de solveurs de relaxation mécanique (Saurel and Abgrall, 1999). Une autre méthode consiste à utiliser un modèle à une vitesse et une pression (Kapila et al., 2001). Cependant, de nombreuses applications font intervenir des interfaces instables entre fluides. On traite habituellement ces zones de mélanges turbulents en utilisant un modèle à une vitesse et en résolvant spatialement les diverses instabilités. Dans de nombreuses applications cela devient impossible en raison du trop grand nombre de « jets » et de « bulles ». De plus, on rencontre des difficultés numériques y compris pour le calcul d'une instabilité isolée (Liska and Wendroff, 2004). Dans ce manuscrit, nous abordons le problème de la modélisation des zones de mélange avec des modèles multiphasiques. Cela pose un sérieux problème de modélisation pour des écoulements évoluant d'une situation où l'interface est bien définie (une seule vitesse) vers une configuration de mélange de fluides à plusieurs vitesses. Cette question a été abordée par Besnard and Harlow (1988), Youngs et al. (1989), Chen et al. (1996), Glimm et al. (1999), Saurel et al. (2003) par exemple. / Multiphase mixtures with velocity disequilibrium are usually modelled with 6 or 7 equations models (Baer and Nunziato, 1986). These models are very efficient to model mixtures with velocity drift effects. They can also be used to model interfacial flows where the respect of interface conditions (continuous normal velocity and pressure) is mandatory. Such aim is usually achieved with the help of stiff mechanical relaxation solvers (Saurel and Abgrall, 1999). Another option is to use single pressure and single velocity models (Kapila et al., 2001). However, many applications involve unstable fluid-fluid interfaces for which flow conditions range from well separated fluids to fully mixed ones. The usual way to deal with these turbulent mixing zones is to use a single velocity flow model and to resolve spatially the various instabilities. However, spatial resolution of these instabilities in many applications is impossible as too many ‘jets' and ‘bubbles' are present. Also, numerical difficulties and large inaccuracies are present even for an isolated instability computation (Liska and Wendroff, 2004). In this work, we address the issue of mixing zone modelling with multiphase flow models. This poses the serious difficulty of model derivation for flows conditions ranging from well defined interfaces (single velocity) to fluid mixtures evolving with several velocities. This issue has been addressed by Besnard and Harlow (1988), Youngs et al. (1989), Chen et al. (1996), Glimm et al. (1999), Saurel et al. (2003) to cite a few. In Saurel et al. (2010) an extension of the Kapila et al. (2001) model was done to deal with permeation effects through material interfaces.
87

Fatores que afetam a estabilidade do leite bovino / Factors affecting the stability of bovine milk

Machado, Sandro Charopen January 2010 (has links)
Entre os anos de 2007 e 2009, no nordeste do Rio Grande do Sul, foi conduzido um estudo para avaliar a ocorrência de leite instável não ácido, fatores que afetam a estabilidade do leite bovino e a relação entre o teste do álcool e o teste de tempo de coagulação do leite. Fez-se um questionário para a tipificação das propriedades, um levantamento mensal do leite de 50 propriedades, e se analisou a acidez, coagulação na fervura e no álcool e tempo de coagulação no tanque, além da composição química, células somáticas e contagem bacteriana. Posteriormente, foi realizado um experimento avaliando dietas com três proporções de concentrado (35, 45 e 55%), por 56 dias, avaliando o número de dias em lactação, produção leiteira, peso, condição corporal, características físico-química do leite, pH ruminal e da urina e composição química do sangue. Complementarmente foram realizados quatro protocolos experimentais para avaliar o efeito da temperatura sobre o teste do álcool, o efeito do citrato sobre a estabilidade do leite, o efeito do uso de capilares de diferentes tamanhos sobre o resultado de tempo de coagulação e o uso de diferentes metodologias analíticas para determinação de lactose no leite. A análise estatística dos dados foi efetuada com o programa SAS (2001), avaliando a frequência de ocorrência de fatores (Proc FREQ), correlação (Proc CORR), variância (Proc GLM) e regressão (Proc REG), sendo que no experimento com animais as médias foram ajustadas utilizando dias em lactação, e os valores iniciais de cada atributo como co-variáveis. Foram observados elevada incidência de LINA, CCS e CBT, pouca interferência da dieta na ocorrência de LINA e na alteração da composição do leite e baixa correlação entre o teste do álcool e o tempo de coagulação no tanque. Não houve relação entre o teste da fervura e os testes do álcool e do tempo de coagulação. O citrato melhorou a estabilidade do leite medida no teste do álcool e no tempo de coagulação. A temperatura do leite (4 x 20°C) não interferiu no resultado do teste do álcool. As dimensões dos capilares de teste do tempo de coagulação modificam os valores obtidos, podendo prejudicar a comparação entre diferentes laboratórios. Entre os fatores testados, os que atuaram sobre a estabilidade do leite no teste do álcool foram: a concentração inicial de álcool capaz de induzir a coagulação, a concentração de cátions divalentes em relação aos monovalentes e o teor de sódio do leite. Em relação ao teste do tempo de coagulação, apenas o seu valor inicial foi significativo. Conclui-se que a ocorrência da instabilidade do leite é elevada, a composição mineral do leite foi a que exerceu maior influência sobre os resultados no teste do álcool, não foram detectados fatores que influenciaram o teste do tempo de coagulação nem o da fervura. Não se pode ainda recomendar outro teste para substituir o teste do álcool. / Between 2007 and 2009 in the Northeastern Rio Grande do Sul, a study was conducted aiming to evaluate the occurrence of unstable non-acid milk, the factors affecting the stability of bovine milk and the degree of relationship between test results and alcohol test coagulation time of milk. Was carried out initially, a questionnaire for the characterization of the properties, then a monthly survey of milk from 50 properties, and examined the acidity (acidity and pH), coagulation test and the boiling alcohol and clotting time in tank, and chemical composition, somatic cell and bacterial count. Later we performed an experiment on animals, which were fed with three different proportions of concentrate (35, 45 and 55%) for 56 days and were evaluated the number of days in milk, milk production, weight, body condition, features physical chemistry of milk, pH and composition of urine and blood chemistry. In addition were performed four experimental protocols to evaluate the effect of temperature on the alcohol test, the effect of citrate on the stability of milk, the effect of using capillaries of different sizes on the results of clotting time and the use of different analytical methodologies for determination of lactose in milk. The statistical analysis was performed with SAS software (2001), evaluating the occurrence of factors (Proc FREQ), correlation (CORR), variance (Proc GLM) and regression (Proc REG), and the experiment animals the means were adjusted using days in milk, and the initial values of each attribute as covariates. We observed high levels of incidence of LINA, CCS and CBT, little interference from the diet in the occurrence of LINA and change the composition of milk and low correlation between the alcohol and the clotting time in the tank. There was no relationship between the boiling test and tests for alcohol and clotting time. Citrate exerted positive action on the stability of milk as the test of alcohol and the clotting time. The temperature of milk during the test (4 x 20 ° C) had no effect on the test result of alcohol. The dimensions of the capillary test of clotting time modify the values and may undermine the comparison between different laboratories. Among the factors tested, acted on the stability of milk alcohol test were: the initial concentration of alcohol to induce coagulation, the concentration of divalent cations compared to monovalent and sodium content of milk. For the test of clotting time, only the initial value was significant. It is concluded that the occurrence of instability of the milk is high, the factors measured, the mineral composition of milk that was the greatest influence on the results in the alcohol, but not detected factors influencing the test of clotting time or to the boil. You can not even recommend another test to replace the alcohol test.
88

OVLIVNĚNÍ EFEKTIVITY STIMULACE VYTRVALOSTNÍ SÍLY PROSTŘEDNICTVÍM CVIČENÍ NA NESTABILNÍCH OPORNÝCH PLOCHÁCH / Affecting the efficiency of stimulation a strenght endurance through exercies on unstable surface

Jebavý, Radim January 2012 (has links)
Affecting the efficiency of stimulation a strenght endurance through exercies on unstable surface In our work we sought to verify the affecting the efficiency of a Strength programme of exercise on unstable surfaces for stimulation of strength endurance abilities, compared to a similar didactic programme conducted on stable surfaces, thus creating an alternative choice for coaches, teachers, and sports instructors. A major element of the didactic process is the quality of the strength training programme on stable and unstable surfaces. When evaluating the overall results of the tests before and after the experimental programme, we come to be of the opinion that the experimental programme manifested itself positively in effectiveness of stimulating strength abilities. The strength programme had an influence on increasing the persistence of strength in dynamic and static regimens. In the case of a strengthening programme on unstable surfaces there was a tendency towards greater growth in the number of repetitions as opposed to programme on a stable base at the beginning of the programme in the case of exercise in a dynamic regimen. Keywords: effectiveness, strength endurance preparation, unstable surfaces, stabilisation system.
89

Fatores que afetam a estabilidade do leite bovino / Factors affecting the stability of bovine milk

Machado, Sandro Charopen January 2010 (has links)
Entre os anos de 2007 e 2009, no nordeste do Rio Grande do Sul, foi conduzido um estudo para avaliar a ocorrência de leite instável não ácido, fatores que afetam a estabilidade do leite bovino e a relação entre o teste do álcool e o teste de tempo de coagulação do leite. Fez-se um questionário para a tipificação das propriedades, um levantamento mensal do leite de 50 propriedades, e se analisou a acidez, coagulação na fervura e no álcool e tempo de coagulação no tanque, além da composição química, células somáticas e contagem bacteriana. Posteriormente, foi realizado um experimento avaliando dietas com três proporções de concentrado (35, 45 e 55%), por 56 dias, avaliando o número de dias em lactação, produção leiteira, peso, condição corporal, características físico-química do leite, pH ruminal e da urina e composição química do sangue. Complementarmente foram realizados quatro protocolos experimentais para avaliar o efeito da temperatura sobre o teste do álcool, o efeito do citrato sobre a estabilidade do leite, o efeito do uso de capilares de diferentes tamanhos sobre o resultado de tempo de coagulação e o uso de diferentes metodologias analíticas para determinação de lactose no leite. A análise estatística dos dados foi efetuada com o programa SAS (2001), avaliando a frequência de ocorrência de fatores (Proc FREQ), correlação (Proc CORR), variância (Proc GLM) e regressão (Proc REG), sendo que no experimento com animais as médias foram ajustadas utilizando dias em lactação, e os valores iniciais de cada atributo como co-variáveis. Foram observados elevada incidência de LINA, CCS e CBT, pouca interferência da dieta na ocorrência de LINA e na alteração da composição do leite e baixa correlação entre o teste do álcool e o tempo de coagulação no tanque. Não houve relação entre o teste da fervura e os testes do álcool e do tempo de coagulação. O citrato melhorou a estabilidade do leite medida no teste do álcool e no tempo de coagulação. A temperatura do leite (4 x 20°C) não interferiu no resultado do teste do álcool. As dimensões dos capilares de teste do tempo de coagulação modificam os valores obtidos, podendo prejudicar a comparação entre diferentes laboratórios. Entre os fatores testados, os que atuaram sobre a estabilidade do leite no teste do álcool foram: a concentração inicial de álcool capaz de induzir a coagulação, a concentração de cátions divalentes em relação aos monovalentes e o teor de sódio do leite. Em relação ao teste do tempo de coagulação, apenas o seu valor inicial foi significativo. Conclui-se que a ocorrência da instabilidade do leite é elevada, a composição mineral do leite foi a que exerceu maior influência sobre os resultados no teste do álcool, não foram detectados fatores que influenciaram o teste do tempo de coagulação nem o da fervura. Não se pode ainda recomendar outro teste para substituir o teste do álcool. / Between 2007 and 2009 in the Northeastern Rio Grande do Sul, a study was conducted aiming to evaluate the occurrence of unstable non-acid milk, the factors affecting the stability of bovine milk and the degree of relationship between test results and alcohol test coagulation time of milk. Was carried out initially, a questionnaire for the characterization of the properties, then a monthly survey of milk from 50 properties, and examined the acidity (acidity and pH), coagulation test and the boiling alcohol and clotting time in tank, and chemical composition, somatic cell and bacterial count. Later we performed an experiment on animals, which were fed with three different proportions of concentrate (35, 45 and 55%) for 56 days and were evaluated the number of days in milk, milk production, weight, body condition, features physical chemistry of milk, pH and composition of urine and blood chemistry. In addition were performed four experimental protocols to evaluate the effect of temperature on the alcohol test, the effect of citrate on the stability of milk, the effect of using capillaries of different sizes on the results of clotting time and the use of different analytical methodologies for determination of lactose in milk. The statistical analysis was performed with SAS software (2001), evaluating the occurrence of factors (Proc FREQ), correlation (CORR), variance (Proc GLM) and regression (Proc REG), and the experiment animals the means were adjusted using days in milk, and the initial values of each attribute as covariates. We observed high levels of incidence of LINA, CCS and CBT, little interference from the diet in the occurrence of LINA and change the composition of milk and low correlation between the alcohol and the clotting time in the tank. There was no relationship between the boiling test and tests for alcohol and clotting time. Citrate exerted positive action on the stability of milk as the test of alcohol and the clotting time. The temperature of milk during the test (4 x 20 ° C) had no effect on the test result of alcohol. The dimensions of the capillary test of clotting time modify the values and may undermine the comparison between different laboratories. Among the factors tested, acted on the stability of milk alcohol test were: the initial concentration of alcohol to induce coagulation, the concentration of divalent cations compared to monovalent and sodium content of milk. For the test of clotting time, only the initial value was significant. It is concluded that the occurrence of instability of the milk is high, the factors measured, the mineral composition of milk that was the greatest influence on the results in the alcohol, but not detected factors influencing the test of clotting time or to the boil. You can not even recommend another test to replace the alcohol test.
90

Colapso de edifício por ruptura das estacas: estudo das causas e da recuperação / Building collapse for piles rupture: study of the causes and recovery

Eduardo Gimenez de Souza 11 April 2003 (has links)
A maior parte dos acidentes em edifícios, causados por falhas de projeto ou de execução, ocorre na fase de construção. Além de causar prejuízos financeiros, eles colocam em risco a vida dos trabalhadores da obra. Porém, mais graves são os acidentes verificados após o término da construção. Além dos prejuízos serem muito maiores, eles podem envolver pessoas de todos os tipos, crianças, mulheres e idosos. São muitos os casos em que o colapso global do edifício decorre de problemas na fundação. Esse é o caso do edifício considerado neste trabalho, localizado no litoral norte do Estado de São Paulo. Trata-se de um edifício para veraneio, em alvenaria estrutural, com garagem no térreo e quatro andares de apartamentos, apoiado em estacas pré-moldadas, cravadas em solo instável. Pouco tempo após a conclusão e parcialmente ocupado, apresentou recalques e patologias significativas que exigiram providências, reforço de pilares de alvenaria inclusive. Antes que fossem detectadas as causas dos recalques, durante uma madrugada, o edifício desabou: em um lado do edifício, o primeiro pavimento encostou-se ao chão. Felizmente, era um dia-de-semana, fora da alta temporada, e não havia pessoas no seu interior. Também o vigia estava fora do edifício e nada sofreu, além de um grande susto. Os objetivos deste trabalho são descrever o problema ocorrido com esse edifício e analisar as causas e as providências possíveis para sua recuperação, já que os andares superiores praticamente nada sofreram. Serão apresentados os resultados de uma investigação no local e de uma análise para determinação dos esforços e das causas da ruptura das estacas, que provocaram o colapso do edifício. Ficou evidente que o aterro localizado sobre o pavimento térreo e o sistema de fundação do edifício não estavam adequados para o tipo de solo do terreno. Tais fatores tiveram papel fundamental para a ruptura do sistema. A importância de se conhecer minuciosamente essas causas transcende a presente obra, pois pelo mesmo motivo, outras construções podem apresentar danos semelhantes. / Most of the buildings accidents, caused by project flaws or of execution, it happens in the construction phase. Besides causing financial damages, they put in risk the workers life. However, more serious accidents are verified after the end of the construction. Besides the damages are larger, they can involve all types of people, children, women and senior. In many cases the global building collapse elapses of foundation problems. That is the case of the building considered in this work, located in the north coast of São Paulo State. Treated of a building for summer vacation, in structural masonry, with garage in the earthy pavement and four floors of apartments, leaning in premolded piles, nailed in unstable soil. After the conclusion and partially in use, it presented repress and significant pathologies that demanded providences, column masonry reinforcement besides. Before detected the repress causes, during one dawn, the building tumbled: on a side of the building, the first pavement was leaned to the ground. Happily, it was a weekday, out of the high season, and there were not people inside. Also the watchmen was out of the building and nothing suffered, besides a great fright. The objectives of this healthy work are to describe the problem happened with that building, to analyze the causes and the possible providences for it recovery, since the superior walks practically nothing suffered. The results of a local investigation, an analysis for determination the efforts and the causes of the piles rupture will be presented, that provoked the building collapse. It was evident that the located embankment on the earthy pavement and the building foundation system, they were not adapted for the soil type of the land. Such factors had fundamental paper for the system rupture. The importance of knowing those causes thoroughly, transcends to present work, because for the same reason other constructions can present similar damages.

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