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Novel Application of Nondestructive Testing to Evaluate Anomalous Conditions in Drilled Shafts and the Geologic Materials Underlying Their ExcavationsKordjazi, Alireza January 2019 (has links)
Drilled shafts are deep foundation elements created by excavating cylindrical shafts into the ground and filling them with concrete. Given the types of structures they support, failure to meet their performance criteria can jeopardize public safety and cause severe financial losses. Consequently, quality control measures are warranted to ensure these foundations meet design specifications, particularly with respect to their structural integrity and geotechnical capacity. Due to their inaccessibility, non-destructive testing (NDT) techniques have received much attention for drilled shaft quality control. However, there are limitations in the NDT tools currently used for structural integrity testing. Moreover, there is no current NDT tool to evaluate conditions underlying drilled shaft excavations and aid in verifying geotechnical capacity. The main objective of this research is to examine the development of new NDT methodologies to address some of the limitations in the inspection of drilled shaft structural integrity and geotechnical conditions underlying their excavations. The use of stress waves in large laboratory models is first examined to evaluate the performance of ray-based techniques for detecting anomalies. The study then continues to investigate the improvements offered by using a full waveform inversion (FWI) approach to analyze the stress wave data. A hybrid, multi-scale FWI workflow is recommended to increase the chance of the convergence of the inversion algorithms. Additionally, the benefits of a multi-parameter FWI are discussed. Since FWI is computationally expensive, a sequential optimal experimental design (SOED) analysis is proposed to determine the optimal hardware configurations for each application. The resulting benefit-cost curves from this analysis allow for designing an NDT survey that matches the available resources for the project. / Civil Engineering
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Provas de cargas estáticas instrumentadas em profundidade em estacas escavadas de grande diâmetro (Estações). / Static loading tests instrumented in large diameter drilled piles.França, Danilo Costa de 30 September 2011 (has links)
Objetivou-se estudar o comportamento de estacas escavadas de grande diâmetro em uma obra de um Shopping Center na cidade de São Paulo. As estacas foram submetidas a carregamentos axiais de compressão, sendo que as estacas foram instrumentadas em profundidade. Utilizou-se de teorias amplamente conhecidas no meio técnico com o propósito de interpretar as curvas carga vs recalque, obtendo-se resultados como os diagramas de transferência de carga ao longo do fuste e atrito lateral unitário, gráficos do produto ES das estacas ensaiadas, gráficos de rigidez das estacas e as duas relações modificadas de Cambefort. O presente trabalho visa conseguir parâmetros que pudessem proporcionar uma redução no comprimento das estacas em obra e apresentar resultados que auxiliem os projetistas no dimensionamento de fundações usando-se estacas escavadas de grande diâmetro, sempre tendo cuidado e critério na extrapolação dos resultados em solos diferentes dos apresentados aqui. / The objective of this Msc Thesis is to study the behavior of large diameter drilled pile in the construction of a shopping mall in Sao Paulo. The piles were subjected to axial compression loads and instrumented in depth. Widely known theories were used to interpret load vs settlement curves, obtaining such results as transfer loads diagrams along the shaft and lateral friction unit, ES product and stiffness grafics of tested piles and two modified Cambefort Laws. This paper aims to achieve parameters that will allow a reduction in pile lengths and to present results that will aid designers in the design of large diameter drilled pile, provided that the needed care is taken when extrapolating results to soils of different geological origins from those presented here.
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Resistance analysis of axially loaded drilled shafts socketed in shaleBurkett, Terry Bryce 05 November 2013 (has links)
An investigation into the load-settlement behavior of two drilled shafts, founded
in shale, is presented. The motivation for this research is to advance the understanding
on how drilled shafts react under loading in stiff clays and shales. The objectives of the
study are to measure the strengths within the subsurface material at the test site, estimate
the unit side shear and unit end bearing of the shale-shaft interaction by running two axial
load tests, and compare the results to the current design methods that are used to predict
the axial capacity of drilled shafts.
A comprehensive field investigation, performed by Fugro Consultants, provided
strength profiles of the subsurface material at the test site. Through the cooperation of
the Texas Department of Transportation (TxDOT), the Association of Drilled Shaft
Contractors, and McKinney Drilling Company, two drilled shafts were installed at a
highway construction site in Austin, Texas. The load tests were performed by Loadtest,
Inc.; using the patented Osterberg-Cell™ loading technique to axially displace the shafts.
Ensoft, Inc. installed strain gauges at multiple levels within the shafts, making it possible
to analyze the shaft mobilization during loading.
Ultimate end bearing values of about 100- and 120-ksf were measured for Test
Shafts #1 and #2, respectively. The current methods for estimating unit end bearing,
developed by TxDOT and the Federal Highway Administration, provide fairly accurate
predictions when compared to the measured information. The ultimate side resistance
obtained near the O-Cell™ in each test was about 20-ksf, however, the measured ultimate
side resistance steadily decreased nearing the tip of the shaft. For the zones where the
side resistance was believed to be fully mobilized, the TxDOT design method accurately
predicts the side resistance. A limited amount of information is currently available for
load tests performed in soils with TCP values harder than 2-in per 100 blows. Additional
load test information should allow for a stronger correlation between TCP tests and unit
resistances for very hard clay-shales, as well as, allowing for further evaluation of the
shale-shaft interaction near the shaft tip. The results presented herein demonstrate the
effectiveness of the current design methods for drilled shafts and the non-uniformity of
side resistance within one- to two-diameters of the shaft tip. / text
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Estudo da resistência à compressão do concreto por meio de testemunhos de pequeno diâmetro e esclerometria / Study of Concrete Strength by means of Small Cores and Sclerometry EssaysCastro, Elisângela de 14 September 2009 (has links)
Fundação de Amparo a Pesquisa do Estado de Minas Gerais / The current method for the verification of the concrete strength to compression consists in
molding test cylinders or taking cores of the structure elements. The Brazilian Code ABNT
NBR 7680:2007 recommends the extraction of cores with a minimum diameter of 100 mm,
preferential. The reduced diameter cores have the objective of facilitating and optimizing
the evaluation of existing structures, avoiding steel sectioning, reducing costs and allowing
the increase of the number of samples. In this line, the sclerometry (for testing the surface
hardness) is a non-destructive technique to evaluate the concrete uniformity, the evolution
of strength along with time, and to estimate the final concrete s strength. This study
presents the results of an experimental research to estimate the compressive concrete s
strength using the sclerometry and the extraction of reduced diameter cores. Some factors
which have relevant influence in the extraction and testing of cores will be hereby
discussed. The investigated variables were: the nominal dimension of the aggregate and the
core s diameter. The sclerometry variability results in the blocks it was studied too. In the
program of rehearsals three concrete series were used with gravel 0, with gravel 1 and with
gravels 1 and 2, maintaining the same relationships for water-cement and aggregatecement.
The sclerometric tests were conducted in concrete blocks of 40 cm x 40 cm x 80
cm and cylinders specimens with 150 mm diameter. The analysis was conducted by
comparison of the results of drilled cores from the blocks with diameters of 150 mm, 100
mm, 50 mm, 32 mm and 25 mm, test specimens with diameters of 150 mm, 100 mm and
50 mm, and sclerometry testing of specimens of 150 mm diameter. Although the
limitations in relation to the number of specimens and some discrepancies between the
used techniques the results had indicated a trend in terms of concrete strength variation. / A resistência à compressão do concreto pode ser obtida mediante ensaios em corpos-deprova
ou em testemunhos extraídos dos elementos estruturais. A Norma Brasileira ABNT
NBR 7680:2007 recomenda extrações com diâmetros preferencialmente maiores que 100
mm. A extração de testemunhos de pequeno diâmetro visa facilitar e otimizar as avaliações
de estruturas acabadas evitando cortes em armaduras, reduzindo custos e permitindo ainda
aumentar significativamente o número de amostras. No mesmo sentido, a esclerometria,
constitui uma técnica para avaliar a uniformidade do concreto, monitorar o
desenvolvimento da resistência ao longo do tempo, e ainda estimar a resistência do
concreto de forma simples, rápida e relativamente barata. A associação da esclerometria
com ensaios em testemunhos constitui uma das melhores formas de estimar a resistência à
compressão do concreto. Este trabalho apresenta os resultados de uma pesquisa
experimental, para a estimativa da resistência à compressão por meio de esclerometria e
extração de testemunhos de pequeno diâmetro. Serão abordados alguns fatores que incidem
na extração e ensaio de testemunhos. As variáveis estudadas foram: a dimensão nominal
máxima do agregado graúdo e o diâmetro do testemunho. Também foi estudada a
variabilidade dos resultados de esclerometria nos blocos. No programa de ensaios foram
utilizadas três séries de concreto, com brita 0, com brita 1 e com britas 1 e 2; mantendo as
mesmas relações para água-cimento e agregado-cimento. Os ensaios esclerométricos foram
realizados em blocos de 40 cm x 40 cm x 80 cm e corpos-de-prova de 150 mm de
diâmetro. A análise foi realizada por comparação entre resultados obtidos em testemunhos
extraídos dos blocos, com diâmetros de 150 mm, 100 mm, 50 mm, 32 mm e 25 mm;
corpos-de-prova de diâmetros 150 mm, 100 mm e 50 mm e esclerometria em corpos-deprova
com 150 mm de diâmetro. Apesar das limitações em relação ao número de
testemunhos e algumas discrepâncias entre as técnicas utilizadas os testemunhos indicaram
uma tendência em termos de variação de resistência. / Mestre em Engenharia Civil
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Provas de cargas estáticas instrumentadas em profundidade em estacas escavadas de grande diâmetro (Estações). / Static loading tests instrumented in large diameter drilled piles.Danilo Costa de França 30 September 2011 (has links)
Objetivou-se estudar o comportamento de estacas escavadas de grande diâmetro em uma obra de um Shopping Center na cidade de São Paulo. As estacas foram submetidas a carregamentos axiais de compressão, sendo que as estacas foram instrumentadas em profundidade. Utilizou-se de teorias amplamente conhecidas no meio técnico com o propósito de interpretar as curvas carga vs recalque, obtendo-se resultados como os diagramas de transferência de carga ao longo do fuste e atrito lateral unitário, gráficos do produto ES das estacas ensaiadas, gráficos de rigidez das estacas e as duas relações modificadas de Cambefort. O presente trabalho visa conseguir parâmetros que pudessem proporcionar uma redução no comprimento das estacas em obra e apresentar resultados que auxiliem os projetistas no dimensionamento de fundações usando-se estacas escavadas de grande diâmetro, sempre tendo cuidado e critério na extrapolação dos resultados em solos diferentes dos apresentados aqui. / The objective of this Msc Thesis is to study the behavior of large diameter drilled pile in the construction of a shopping mall in Sao Paulo. The piles were subjected to axial compression loads and instrumented in depth. Widely known theories were used to interpret load vs settlement curves, obtaining such results as transfer loads diagrams along the shaft and lateral friction unit, ES product and stiffness grafics of tested piles and two modified Cambefort Laws. This paper aims to achieve parameters that will allow a reduction in pile lengths and to present results that will aid designers in the design of large diameter drilled pile, provided that the needed care is taken when extrapolating results to soils of different geological origins from those presented here.
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Stavebně technologický projekt výstavby centrální nabíjecí stanice v Púchově / Construction-technological project for the construction of a central charging station in PúchovStopka, Peter January 2019 (has links)
This diploma thesis focuses on the construction of a construction technological project for the construction of the Central Charging Station in Púchov. The building is located in the industrial area of Púchov and in the area of Continental Matador Rubber. In the thesis is elaborated technical report for building technological project, co-ordination situation of construction with wider transport routes, time and financial object plan, study of the realization of the main technological stages, construction site design, design of main building machines and mechanisms, time schedule of main building, securing material resources for the monolithic part of the building. In the thesis are made, technological rules for drilled pilots and ceiling structure above the first overground floor. Technological regulations follow control and test plans. Other assignments that have been made in this work, such as the occupational safety and health plan, the design and comparison of cranes and the item budget.
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Obchodní a administrativní centrum Poděbradská - stavebně technologický projekt / Poděbradská Commercial and Administrative Center - construction technology projectKmeť, Peter January 2020 (has links)
This diploma thesis focuses on construction technology preparation of shopping center in Prague 9, Vysočany. The aim of this work was to choose an appropriate construction process. The thesis contains general information about construction with construction technology project, its financial and time consuming, facilities for construction and traffic situation in the surroundings of the construction, design of main machinery and mechanisms, technological regulation with control and test plan. The diploma thesis is focused on piles realization.
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Návrh výběru druhu topných desek dle technologických a ekonomických aspektů / Suggestion of Type Selection of heating Plates According to Selected AspactsJuřenová, Jana January 2008 (has links)
Description and structure of the company. Description and characteristic of type of heating plates and heating medium. Analysis of the current selection of heating plates. Technological and economics aspects. Total estimation of aspects and suggestion of the best suitable alternate.
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Zajištění náhradních zdrojů vody obklíčené nemovité věci v cizím areálu / Provision of alternative water sources for a real estate surrounded by foreign propertyKukol, Jan January 2015 (has links)
The first part of this thesis is focused on water wells and their classification. A big part of this thesis is an essay on groundwater. This thesis also examines the various technical parts of drilled wells and dug wells. The design of pump is discussed briefly. The second part of this thesis is focused on objective and financial complexity of proposed solutions.
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Obytný soubor Fialka-Říčany-Vybraná část STP / RESIDENTIAL Fialka-Říčany-SELECTED PARTS OF THE CTPMachač, Ondřej January 2012 (has links)
Presented work deals with the residential complex Fialka in Ricany, especially with the building A. It is a study of main technological phases, focused on special foundation building - drilled piles and masonry. This work shows a comparison of the former solution of masonry with the proposed alternative.
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