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Acquisition Of Field Data For Agricultural TractorKoyuncu, Atayil 01 June 2006 (has links) (PDF)
During the operations of an agricultural tractor, front axle and front axle support encounter the worst load conditions of the whole tractor. If the design of these components is not verified by systematic engineering approach, the customers could face with sudden failures. Erkunt Agricultural Machinery
Company, which is located in Ankara, has newly designed and manufactured the front axle support of its agricultural tractors. In this study, the design of 2WD (Wheel Drive) Erkunt Bereket Agricultural Tractor& / #8217 / s front axle support has been verified by developing a verification method, which involves testing the tractor on a special test track and field and together with the computer aided engineering analysis, in order to prevent such failures in the lifetime of the tractor.
For this purpose, a strain gage data acquisition system has been designed to measure the strain values on the component, while the tractor is operating on a
test track and field. The locations of the strain gages have been determined by simulating the selected design load cases through finite element method. Measuring the maximum strains for the front axle support that have been experienced by the tractor while operating, the stress values have been calculated and the design safety has been investigated considering the material& / #8217 / s tensile strength. Secondly, the fatigue life of the component regarding the acquired strain
data has been predicted. These processes have led the company to verify the design of the front axle support.
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Determinação da condutividade hidráulica não saturada de solos residuais com o permeâmetro Guelph e ensaios de laboratório / Determination of the hydraulic conductivity no saturated of residual soils with the Guelph permeameter and laboratory testsLisboa, Rafael Luis Lobato 10 February 2006 (has links)
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Previous issue date: 2006-02-10 / Hydraulic conductivities of three non-saturated soils of the Viçosa region were studied with field tests, using the Guelph permeameter, and laboratory tests. In the field, the tests were performed with one and two hydraulic head heights. The corresponding results were analyzed with theoretical models proposed by REYNOLDS and ELRICK (1985). In the laboratory, water retention curves and saturated hydraulic conductivities of the soils were determined, with which variation of the hydraulic conductivities with suction were obtained using VAN GENUCHTEN (1980) and GARDNER (1958) empirical formulations. Finally, the non-saturated hydraulic conductivities obtained with the Guelph permeameter and the ones determined in the laboratory were compared. With the exception of soil 03, in which the walls of the hole made to execute the field test smeared, the saturated hydraulic conductivities values obtained in the field and in the laboratory were similar. With respect to the hydraulic conductivities variation with suction, it was verified that field and laboratory results agreed better when GARDNER (1958) model was used to represent the water retention curves than when the VAN GENUCHTEN (1980) model was used. / A condutividade hidráulica de três solos não saturados da região de Viçosa-MG é estudada através de ensaios de campo, empregando o permeâmetro Guelph, e ensaios de laboratório. No campo, os ensaios foram realizados com uma e duas alturas de carga. Os resultados obtidos foram analisados com os modelos teóricos proposto por REYNOLDS e ELRICK (1985). No laboratório, as curvas de retenção de água dos solos e as condutividades hidráulicas saturadas foram determinadas, o que possibilitou a determinação da variação da condutividade hidráulica com a sucção, através das fórmulas empíricas de VAN GENUCHTEN (1980) e GARDNER (1958). Por fim, os valores da condutividade hidráulica não saturada fornecidos pelo permeâmetro Guelph foram comparados com os obtidos no laboratório. Com exceção do solo 03, no qual as paredes do furo escavado para a execução do ensaio de campo colmataram, as condutividades hidráulicas saturadas dos solos obtidas no campo e no laboratório foram praticamente iguais. Com relação à variação da condutividade hidráulica com a sucção, verificou-se que os resultados de campo e laboratório tiveram uma maior concordância quando se usou o modelo de GARDNER (1958) para representar a curva de retenção de água dos solos do que quando se usou o modelo de VAN GENUCHTEN (1980).
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Avaliação de camadas de proteção para geomembranas de PVC e PEAD / Assessment of the performance of protective layers for PVC and HDPE geomembranesKarla Maria Wingler Rebelo 03 February 2009 (has links)
O presente trabalho investiga o desempenho de geotêxteis e de solos como elementos de proteção para geomembranas de polivinil clorado (PVC) e de polietileno de alta densidade (PEAD). Foram utilizadas geomembranas de PVC com espessuras de 1,0 e 2,0 mm e de PEAD com espessuras de 1,5 e 2,0 mm. Como camadas de proteção utilizaram-se geotêxteis não tecidos de poliéster (PET), com gramaturas de 130, 300, 400 e 600 g/\'M POT.2\', e de polipropileno (PP), com gramatura de 400 e 600 g/\'M POT.2\', além de uma areia de granulometria fina a média e uma areia argilosa típica da região Centro-Oeste do Estado de São Paulo. O estudo foi conduzido através da construção de um aterro experimental para simulação dos danos de instalação em campo e da realização de ensaios índice e de desempenho em laboratório. A eficiência dos materiais de proteção foi avaliada através da análise qualitativa e quantitativa das amostras de geomembranas danificadas. Os resultados dos ensaios de laboratório índice mostraram que a introdução do geotêxtil aumenta a resistência à punção da geomembrana, e que o acréscimo de resistência é função das características de resistência à tração do geotêxtil e da geomembrana. O maior incremento de resistência à punção foi observado na geomembrana com menor resistência à tração. Os resultados dos ensaios de campo mostraram que a introdução do elemento de proteção reduz os danos mecânicos apesar da alteração de algumas das propriedades físicas e de desempenho nas geomembranas. Da análise dos resultados, verificou-se que a eficiência dos geotêxteis no campo não é função de suas características de tração, conforme constatado nos ensaios índices. A análise também sugere que os danos mecânicos no campo foram mais intensos do que nos ensaios de desempenho em laboratório. / The performance of non-woven geotextiles and soils as protection elements of polyvinyl chloride (PVC) and high density polyethylene (HDPE) geomembranes is studied. The materials used comprised PVC geomembranes of 1,0 and 2,0 mm thickness and HDPE geomembranes of 1,5 and 2,0 mm thickness while the protective layers were of non-woven polyester (PET) geotextiles with mass per unit area of 130, 300, 400 e 600 g/\'M POT.2\' and polypropylene (PP) with mass per unit area of 400 e 600 g/\'M POT.2\'. It was also used protective layers made of a fine to medium sand and a typical clayey sand of central area of the State of São Paulo. The study was based on an experimental landfill built to simulate the damage associated to construction procedures and on index and performance laboratory tests. Through qualitative and quantitative analysis of damaged geomembranes, the behavior of each protective element was evaluated. Index laboratory test results have shown that the geotextile is able to increase the geomembrane puncture strength and that the strength increase is related to the tensile strength of geotextile and geomembrane. For similar geotextiles, the larger increase in puncture strength was observed for the geomembrane that presented the lower tensile strength. Visual observation of field tests has shown that the introduction of protective layers reduces the mechanical damage; however some physical and performance properties of geomembrane have changed. It was also observed that the performance of geotextiles in the experimental landfill does not depend on the tensile strength, as observed in laboratory index tests. Test results also suggest that field damage associated to the landfill construction are more intense than that observed in laboratory tests such as the dynamic puncture test.
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Avaliação de trechos de pavimentos experimentais construídos com materiais alternativos na região metropolitana de GoiâniaMarques, Michelle de Oliveira 27 August 2012 (has links)
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Previous issue date: 2012-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the Federal University of Goias (UFG) some researches have been developed focus on the
importance of the alternative materials study for urban paving in substitution to the traditional
materials used in the area, as the lateritic gravel. These studies contemplated the construction
of experimental road pavements divided in sections in function of the materials composition
used for the subbase and base layers execution, aiming the evaluation of the pavement
performance when submitted to the real traffic in roads with low to medium traffic volume.
Since 2004, three experimental roads were built, being two in the city of Goiania-GO and one
in Aparecida of Goiania-GO. The no conventional and environmental correct materials used
in those works were: civil construction waste, quarry waste, phosphogypsum and mixtures of
fine soil found at the place of the work with crushed rock or lime. As the periodic monitoring
is of great importance for the constant evaluation of the behavior of those pavements, this
research had as objective monitors the existent roads in the year of 2011 and to compare the
results obtained with the one of the previous studies. For so much, several field tests were
done in two different periods: one of dry and other rainy. The field tests were executed with
the following equipments: Benkelman beam, plate bearing, Dynamic Cone Penetrometer
(DCP) and PenetrometreAutonomeNumeriqueDynamique equal AssistéOrdinatur (PANDA),
so much with the cone of 2 cm2 as with the one of 4 cm². Besides, samples of the structural
layers of the pavements and subgrades were collected for water content verification in the two
periods of tests. At the end of each test the comparison of the roads performance was done
along the time from the construction period. In general, it is observed that all the alternative
materials used in the experimental pavements have been presenting similar behavior to the
lateritic gravel, showing application viability. / Têm sido desenvolvidas na Universidade Federal de Goiás (UFG) pesquisas sobre a apliação
de materiais alternativos para pavimentação urbana em substituição aos materiais tradicionais
utilizados na região, como o cascalho laterítico. Alguns dos estudos realizados envolveram a
construção de trechos de pavimentos experimentais divididos em subtrechos com diversas
composições de materiais utilizados para execução das camadas de sub-base e base. Foi
avaliado o comportamento dos mesmos submetidos à solicitações reais em vias de baixo a
médio volume de tráfego. Desde 2004 foram construídos três trechos experimentais, sendo
dois na cidade de Goiânia-GO e um em Aparecida de Goiânia-GO. Dentre os materiais não
convencionais ambientalmente corretos utilizados nessas obras têm-se: resíduo da construção
e demolição (RCD), resíduos de pedreira, fosfogesso e misturas de solo argiloso encontrado
no local da obra com brita ou com cal. Considerando que periódico é de grande importância
para a avaliação do comportamento desses pavimentos, esta pesquisa teve como objetivo
monitorar os trechos existentes no ano de 2011 e comparar os resultados obtidos com os dos
estudos anteriores. Para tanto, foram realizados diversos ensaios de campo em dois períodos
distintos: um de seca e outro chuvoso. Foram executados ensaios com os seguintes
equipamentos: viga Benkelman, prova de carga sobre placa, Dynamic Cone Penetrometer
(DCP) e Penetrometre Autonome Numerique Dynamique Assisté par Ordinatur (PANDA),
tanto com a ponteira de 2 cm2 como com ade 4 cm². Além disso, foram coletadas amostras
das camadas estruturais dos pavimentos e dos subleitos para verificação do teor de umidade
nos dois períodos de ensaios. Ao final de cada ensaio foi realizada a comparação de
desempenho dos trechos ao longo do tempo desde o período de construção. De uma forma
geral, observa-se que todos os materiais alternativos utilizados nos trechos experimentais têm
apresentado comportamento similar ao do cascalho, mostrando à viabilidade de sua utilização.
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Adaptação do teste de Borsetto para avaliação anaeróbia de jovens corredoresSantos, Francielle Pereira 14 August 2017 (has links)
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Previous issue date: 2017-08-14 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Testes de laboratório e de campo são utilizados para avaliação da potência anaeróbia (PAn) e capacidade anaeróbia (CAn). Os testes de campo são alternativas práticas, de fácil acesso e em geral de baixo custo, considerados mais aplicáveis à rotina de avaliação em equipes de atletismo. O teste de Borsetto (TBor 200 m) é um teste de campo na qual o avaliado deve correr 1000 m em intensidade submáxima e em seguida 200 m em esforço máximo, para avaliar a velocidade de corrida gerada por potência lática. Este método minimiza a velocidade gerada por glicólise aeróbia, o que o torna um teste eficiente para avaliação anaeróbia. O tempo e a velocidade de corrida de 300 m tem sido utilizados para avaliação da CAn. Desta maneira o objetivo do presente estudo é verificar se a adaptação do Teste de Borsetto, com utilização da corrida de 300 m em esforço máximo após os 1000 m corridos em velocidade submáxima (TBor 300 m) seria mais eficiente que o TBor 200 m para esgotar a reserva anaeróbia (RAn) e, por essa razão, avaliar de forma mais específica a CAn de jovens corredores; verificar se o TBor 200 m e o TBor 300 m podem discriminar CAn entre diferentes grupos de corredores e verificar a relação entre as variáveis frequência cardíaca final (FC final.), Índice de fadiga (IF) e Lactato máximo (Lacmáx) com os resultados dos testes. Participaram do estudo 15 jovens do sexo masculino (8 velocistas e 7 meio-fundistas) com média de idade de 17,0 ± 1,6 anos, massa corporal de 62,66 ± 7,67 kg, estatura de 176,34 ± 5,80 cm que treinam atletismo há no mínimo a 10 meses e no máximo a 96 meses. As avaliações ocorreram em 4 sessões, sendo realizados: Anamnese, avaliação antropométrica, Teste de Léger e Boucher para obter o pico de velocidade aeróbia (PVA); e em ordem randomizada, o TBor 200 m e o TBor 300 m, para obter: RAn, Lacmáx, IF, FC final e percepção subjetiva de esforço (PSE) de cada teste. A PSE final e a FC final indicam que os atletas realizaram esforço intenso nos testes. A RAn do TBor 200 m é maior que a RAn do TBor 300 m tanto para velocistas como para meio-fundistas, ambos os testes podem discriminar CAn entre os grupos. Os velocistas têm maior CAn e os meio-fundistas tem maior PVA. Tempo e velocidade das corridas máximas indicam que o TBor 300 é influenciado pelo metabolismo aeróbio, pois mostrou correlação significativa com o PVA. O Lacmáx, IF e FC final foram iguais para os dois grupos e não mostraram correlação com os resultados dos testes, exceto a FC final do TBor 300 m que mostrou correlação com a RAn%. Conclui-se que o TBor 200 m é eficaz para avaliar a CAn, visto que diferencia grupos treinados de jovens corredores e a avaliação da RAn não é influenciada pelo metabolismo aeróbio neste teste. / Laboratory and field tests are used to evaluate Anaerobic Power (AnP) e Anaerobic Capacity (AnC). The field tests are easy access, generally low-cost, practical alternatives and are considered more applicable to the evaluation routine in athletics teams. The Borsetto test (TBor 200 m) is a field test in which the evaluated must run 1000 m in submaximal effort, and then 200 m in maximal effort to evaluate the running speed produced by lactic power.
This method minimizes the speed produced by the aerobic glycolisis, which makes it an efficient test for anaerobic evaluation. The time and speed of a 300 m run has been used for AnC evaluation. In this way, the objective of this study is to verify if the adaptation of Borsetto Test, using 300 m run in maximal effort after 1000 m run in submaximal effort (300 m TBor) would be more efficient than the 200 m TBor to exhaust anaerobic reserves (AnR) and, for this reason, to evaluate the AnC of young runners in a more specific way; verify if the 200 m TBor and the 300 m TBor can discriminate AnC in different groups of runners and verify the relation between final heart rate (Final HR), Fatigue rate (FR) and maximal lactate (ML) variables with the tests results. 15 young males participated in the study (8 sprinters and 7 middle distance runners) at about 17,0 ± 1,6 years old, 62,66 ± 7,67 kg of body mass, 176,34 ± 5,80 cm height who practice athletics for at least 10 months and at most 96 months. The evaluations happened in 4 meetings, being performed: anamnesis, anthropometric evaluation, Léger and Boucher tests to obtain aerobic speed peak (ASP); and randomly, the 200 m TBor and the 300 m TBor, to obtain: AnR, Max lactate, FR, final HR and subjective effort perception (SEP) of each test. Final SEP and final HR indicate that the athletes performed intense effort on the tests. The 200 m TBor AnR is higher than the 300 m TBor both for sprinters and long distance runners, both tests can discriminate AnC between the groups. Sprinters have higher AnC and long distance runners have higher ASP. Time and speed of maximal runs indicate that the 300 m TBor is influenced by aerobic metabolism, because it has shown significant correlation with ASP. Maximal lactate, FR and Final HR were the same for both groups and haven’t shown correlation with the results of the tests, except for the 300m TBor Final HR that has shown correlation with AnR%. It can be concluded that the 200 m TBor is efficient to evaluate the AnC, as it discriminates trained groups of young runners and AnR evaluation is influenced by aerobic metabolism on this test.
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Komparace úrovně rovnováhových schopností sportovních gymnastek a cvičenek Teamgymu. / Comparison of the level of balance abilities of artistic gymnasts and TeamgymsDuspivová, Lucie January 2020 (has links)
Title: Comparison of balance of abilities of artistic gymnasts and TeamGym gymnasts Objectives: The aim of this work is to describe the relationship between selected factors and performance in selected balance tests of groups of artistic gymnasts and TeamGym gymnasts and at the same time to verify the effect of the balance beam exercise on the balance ability of TeamGym gymnasts. Methods: Field tests were chosen for data acquisition: stand on dominant and non- dominant limb with closed and open eyes, walking back on balance beam and bench, jumps to balance position (track). Furthermore, a questionnaire survey was used. The obtained data were evaluated by means of Wilcoxon tests for two dependent and independent samples, correlation analysis, materiality investigation for non-parametric data and means of descriptive statistics. The data were also examined in terms of the percentages of the achieved maxima. The intervention method was chosen to verify the influence of the exercises on the balance beams. Results: The relationship of the direct proportion between age and performance in walking back on bench and track test was confirmed, and between height and performance in stand-up tests and track run were confirmed. In addition, a better level of balance skills in artistic gymnasts was demonstrated...
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An Investigation of Disintegration Behavior of Mudrocks Based on Laboratory and Field TestsGautam, Tej P. 29 November 2012 (has links)
No description available.
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[es] APLICACIÓN DE TÉCNICAS PROBABILÍSTICAS Y ESTADÍSTICAS EN LA EVALUACIÓN DE LA REPRESENTATIVIDAD DE RESULTADOS DE ENSAYOS IN SITU / [pt] APLICAÇÃO DE TÉCNICAS PROBABILÍSTICAS E ESTATÍSTICAS NA AVALIAÇÃO DA REPRESENTATIVIDADE DE RESULTADOS DE ENSAIOS IN SITU / [en] APPLICATION OF PROBABILISTIC AND STATISTIC TECHNIQUES IN THE EVALUATION OF THE ADEQUACY OF IN SITU EXPERIMENTAL RESULTSGERSON JACQUES MIRANDA DOS ANJOS 26 May 2000 (has links)
[pt] O estudo da variabilidade das propriedades dos solos, como resistência de
ponta (qc), resistência não drenada (Su) e poro pressão (∆u), é a principal meta desta tese.
Utilizam-se de técnicas de Probabilidade e Estatística em ensaios in situ como piezocone,
palheta e pressiométricos tipo Menard e Auto-Perfurante.
Em um primeiro momento, os resultados de Su são analisados através de
retas médias obtidas pela comparação dos resultados de Su, em depósitos em que o teor de
umidade é maior ou igual ao limite de liquidez e em depósitos em que a umidade é menor
que o limite de liquidez.
A determinação da Função Densidade de Probabilidade (FDP) para os
ensaios de piezocone em solo residual - Campus Experimental da PUC-RIO, argila mole da
Baixada Santista e na Barragem de Rejeito de Ouro em Paracatu - MG, também será objeto
de estudo a melhor FDP, entre a Normal e a Lognormal.E por fim, estuda-se o parâmetro chamado escala de flutuação que,
juntamente com a média e o desvio-padrão, descreve com maior eficiência a variabilidade
espacial das propriedades dos solo, utilizando-se de duas metodologias: uma para o ensaio
de piezocone, baseada no modelo de campo aleatório proposta por Vanmarcke, e a outra
para os ensaios palheta e pressiômetros Menard e Auto-Perfurante, através do estudo da
função de autocorrelação, baseada no trabalho de Asaoka e Grivas. / [en] It is well known that there is an inherent variability in
the values of undrained shear strength of soil collected at
different depths. In the case of natural deposits, this
variability is attributed to the randomness associated with
the geological processes involved in the formation of the
deposits.
The study on spatial variability of soil properties like
undrained shear strength (Su), cone bearing (qc) and pore
pressure(delta u), is the main goal of this thesis.
Probabilistic and Statistical approaches have been applied
to analyze results of cone penetration tests performed in
quartenary soft clay deposits located in the Baixada
Santista - Sao Paulo, gneiss residual soil profile -
Experimental Campus - PUC-RIO and also in a Tailing dam at
Paracatu - MG.
Vane, Menard and self-boring Pressuremeter tests have been
used to establish the scale of fluctuation through the
study of autocorrelation functions in a quartenary soft
clay deposit located in the Baixada Santista area.
The results of that study have shown that, for piezocone
tests in the residual soil and soft clay in the Baixada
Santista, the best Probability Density Function will be
Lognormal, and that fluctuation scale obtained from
piezocone, Vane, Menard and self-boring pressuremeter tests
are an important descriptor of soil variability. / [es] El estudio de la variabilidad de las propriedades de los suelos tales como resistencia de punta (qc), resistencia no
drenada (Su) y poro presión (∆u), es la meta principal de esta tesis. Este estudio utiliza técnicas de probabilidades
y estadística en ensayos in situ como piezocone, Paleta, presiometros Menard y Auto-Perforante. En un primer
momento, se analizan los resultados de Su a través de rectas médias obtenidas por comparación de los
resultados de Su, en depósitos donde la humedad es mayor o igual al Límite de Líquidez y en depósitos en
que la humedad es menor que el límite de líquidez. La determinación de la Función de Densidad de
Probabilidad (FDP) para los ensayos de piezocone en suelo residual - Campo Experimental de la PUC-RIO, arcilla
blanda de la Baixada Santista y en Barragem de Rejeito de Ouro, en Paracatu - MG, también será objeto de
estudio la mejor FDP, entre la Normal y la Lognormal. Y por fin, el estudio del parámetro llamado escala de
fluctuación que, conjuntamente con la media y el error estándar descriven com mayor eficiencia la variabilidad
espacial de las propriedades de los suelos, haciendo uso de dos metodologías. Una para el ensayo de piezocone
y la otra para los ensayos Paleta, presiometros Menard y Auto-Perforante a través del estudio de la función de
autocorrelación.
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EXPERIMENTAL AND ANALYTICAL STUDY OF THE DYNAMIC RESPONSE OF STEEL BEAMS AND COLUMNS TO BLAST LOADINGNassr, Amr A. 10 1900 (has links)
<p>In this thesis the dynamic response of wide-flange steel beams and columns to blast loading was experimentally evaluated. A total of twenty six steel members were field tested using live explosives, where the charge size ranged from 50 to 250 kg of ANFO and the ground stand-off distance from 7.0 to 10.3 m. Blast wave characteristics, including incident and reflected pressures were recorded. In addition, time-dependant displacements, accelerations, and strains at different locations along the steel members were measured, and the post-blast damage and mode of failure of the test specimens were observed. This study also presented detailed analysis of the experimental data. The blast load characteristics were compared with those obtained using the Technical Manual UFC 3-340-02 model (UFCM). The spatial and temporal variations of strain rate were computed from the recorded strain time histories and analyzed. In addition, time-dependant deformations were analyzed to study the contributing modes of vibration in the dynamic response using Power Spectral Density (PSD) function. Moreover, the effect of the axial load on the maximum deformations, vibration periods, strain rates, and contributing modes in the dynamic response were study by comparing the beam results with the column results tested in the same blast shots.</p> <p>The experimental results were compared with those obtained from an equivalent Single-Degree-of-Freedom (SDOF) model, which included material nonlinearity, strain rate effect, and <em>P-δ</em> effect. To account for strain rate effect on member stiffness and strength, its full moment-curvature response is determined by dividing its cross-section into a number of layers and a strain rate-dependent stress-strain relationship, based on the Cowper-Symonds strain rate model, was used to capture the nonlinear stress distribution over the section. The <em>P-δ</em> effect was modelled using the equivalent lateral load (ELL) method to simulate the secondary moment due to axial load. To determine the effects of higher modes of vibration and the variation of steel member mechanical properties along its length on its dynamic response, the test steel members were also analyzed using Multi-Degree-of-Freedom (MDOF) models, based on Finite Element Modelling (FEM). These dynamic models were also used to investigate the effect of axial-bending interaction and dynamic stability of columns. In addition, the results of the dynamic models were used to evaluate the results of the Moment Magnification Factor (MMF) commonly used in the interaction formulas to design steel beam columns under blast. Moreover, the effect of strain rate caused by the blast loading on the local stability of steel columns was also evaluated insofar as it might lead to a shift in the governing mode of failure.</p> <p>Results showed the UFCM pressure predictions compared reasonably well with the measured pressure in the positive phase in terms of both the peak pressure and overall time variations. Results also showed that when proper accounting for secondary-moment due to axial load and strain rate effect on the member resistance function, the SDOF model adequately captured both the overall response, such as the time-dependant deformations and internal forces, and instability behaviour of steel columns under blast loading. It is also shown that using MMF method overestimates the column capacity for ductility ratios <em>µ</em> greater than one, irrespective of the axial load to Euler elastic buckling load ratio (<em>P</em>/<em>P</em><sub>e</sub>). Also for <em>P</em>/<em>Pe</em> > 0.5, even if <em>µ</em> >1.0, the UFC method still overestimates the actual column capacity. The results of the dynamic models were used to generate stability diagrams for the assessment of the critical load and Pressure-Impulse (PI) diagrams for checking the column performance against the allowable deflection limits, which can be implemented in design standard of steel structures under blast loading.</p> / Doctor of Philosophy (PhD)
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Validité du test cardiovasculaire à doubles marches, le CLW, à prédire les performances du test navette de 20 mètres et du test 12 minutes de Cooper chez les étudiants (es) âgés de 17 à 20 ans du Cégep de l’Abitibi-Témiscamingue / Validity of double steps test, CLW, to predict performence of 20 meters shuttle run and the 12 minutes run of Cooper on young students aged between 17 and 20 years olds of Cégep de l’Abitibi-TémiscamingueCharles, Ugo January 2014 (has links)
Résumé : Le CLW (Chiasson, Lasnier et Whittom, 2005), un test à doubles marches sous-maximal (Step test) qui mesure le VO[indice inférieur 2max], requiert peu d’espace et exige 6 min 30 s à réaliser. Or, est-ce que le CLW peut remplacer un test de course comme le test navette de 20 mètres (Léger et Gadoury, 1989) ou le 12 minutes de Cooper (Cooper, 1968) lorsque l’espace n’est pas adéquat pour les effectuer?
Soixante étudiants (es) du cégep de l’Abitibi-Témiscamingue âgés de 17 à 20 ans ont été sélectionnés à l’intérieur des cours d’éducation physique et ont accompli les trois tests physiques.
L’objectif premier était de vérifier la capacité du CLW à prédire les résultats des tests de course navette de 20 mètres (Léger et Gadoury, 1989) et le 12 minutes de Cooper (Cooper, 1968).
Deuxièmement, connaître si l’ajout d’un troisième palier au CLW était nécessaire pour une meilleure similarité entre les tests. Finalement, déterminer si une catégorisation des résultats permet une meilleure concordance.
Cette étude n’a pas été en mesure de démontrer que le CLW est capable de prédire les
performances des tests de course navette de 20 mètres et le 12 minutes de Cooper chez les étudiants du cégep de l’Abitibi-Témiscamingue. Par le fait même, l’ajout d’un troisième palier n’améliore pas de façon significative la capacité du CLW à prédire les performances des tests de course. Toutefois, le CLW s’avère être un meilleur prédicteur de la performance chez les femmes lorsque nous comparons les données brutes du VO[indice inférieur 2max]. Étant donné certaines faiblesses de cette étude, dont l’absence d’une mesure directe, nous recommandons des recherches futures pour comparer ces trois tests à une mesure directe du VO[indice inférieur 2max] pour déterminer lequel de ces tests est le plus approprié pour la clientèle générale du cégep de l’Abitibi-Témiscamingue. // Abstract : The CLW (Chiasson and Lasnier Whittom , 2005), a double steps test to measure VO[subscript 2max], has the advantage of being submaximal , to require little space and require only 6 min 30 s to achieve. Is the CLW can replace a running test as 20 meters shuttle test (Léger and Gadoury, 1989) or 12 minutes of Cooper (Cooper, 1968) when the space is not adequate to perform those running tests? Until now, no writing is not publicly available on the CLW and no one has yet measured the capacity of CLW to predict performance in the 20 meters shuttle test and test 12 minutes Cooper. Sixty students, divided by sex, selected within the physical education classes, have completed those physical tests. The objective of this research was to verify the capacity of CLW to predict the results of 20 meters shuttle run and the 12-minutes Cooper. In a second step, compared the results obtained to know if adding a third level to CLW is necessary for a better match between these tests. Finally, we grouped the values in class to determine if we can get a better result.
This study did not demonstrate the CLW is able to predict the performance of 20 meters shuttle run test and 12 minutes of Cooper among our groups. Thereby, adding a third level does not improve significantly its ability to predict the performance of the run tests. However, the CLW proves to be a better predictor of performance in women when comparing raw data results obtained. Given some weaknesses of this study, as the a direct mesure to compare with, then we recommend that futures researches must compare these three tests with a direct measure of VO[subscript 2max] to determine which of these tests is most appropriate.
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