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Dissertations / Theses on the topic 'Non-destructive structural evaluation'

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1

Grammatikos, S. "Structural integrity assessment of aerostructures using innovative Non-Destructive Evaluation Techniques." Thesis, University of Bath, 2013. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636522.

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2

Hiwarkar, Vikrant. "Nonlinear dynamics of cracked structures for non-destructive evaluation." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6712.

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The power plant and aerospace industries have been facing a huge loss, due to structural failure. The structural failure occurs due to the presence of the crack in it. Hence, it becomes necessary to monitor the structural health under operating condition. Most of the techniques, for structural health monitoring are used for a specific purpose. Some of these techniques require structure dismantling, which is very much expensive and time consuming. So the vibration based structural health monitoring is advantageous, compared to other techniques. Most of the vibration based Structural Health Moni
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3

Mierczak, Lukasz. "Evaluation of structural integrity of steel components by non-destructive magnetic methods." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/89463/.

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Magnetic non-destructive methods utilising the Magnetic Flux Leakage (MFL) and Magnetic Barkhausen Noise (MBN) phenomena are widely used in the evaluation of the structural integrity of steel components. The MFL method is effectively applied for in-service flaw monitoring of oil and gas pipelines, fuel storage tank floors and rails; whereas the MBN method, due to high sensitivity of Barkhausen emission to residual and applied stress, has become one of the most popular NDE tools for investigating this condition of steels. Despite the affirming research and successful applications, which helped
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4

Sha'at, Ali Abdel-Hamid Ali. "Evaluation of highway and airport pavement life based on non-destructive structural assessment techniques." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335998.

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5

Kaynak, Mehmet. "Non-destructive Testing Of Columns Under Axial Compression Using Tranverse Vibration Technique, And Ultrasonic Approaches." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/1260465/index.pdf.

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The level of axial compressive load on an existing column is one of the most important parameters to be known. This thesis aims to investigate current state of the art of NDT techniques, their application, and investigate alternative ways of using current technology to estimate the axial compressive load on columns. For this purpose, transverse vibration technique, ultrasonic pulse velocity method, and waveform and frequency content evaluation of ultrasound are investigated and implemented. Analytical and experimental studies on column transverse vibration frequency and axial load relationship
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6

Gauthier, Camille. "Analyse acoustique et physico-chimique du couplage de solides élastiques : étude de l'adhésion dans les collages structuraux." Thesis, Le Havre, 2016. http://www.theses.fr/2016LEHA0018/document.

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Cette thèse s’inscrit dans le contexte de l’ANR ISABEAU (Innovating for Structural Adhesive Bonding Evaluation and Analysis with Ultrasounds, associant des physico-chimistes et des acousticiens) et cherche à apporter des connaissances nouvelles sur l’évaluation par ultrasons du niveau d’adhésion d’un collage structural par ondes de Lamb. La première partie porte sur l’aspect cohésif et particulièrement sur l’influence du paramètre de réticulation de réseaux époxys sur les courbes de dispersion des ondes de Lamb. La deuxième partie est consacrée à la caractérisation de niveaux d’adhésion dans u
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7

Levine, Ross M. "Ultrasonic guided wave imaging via sparse reconstruction." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51829.

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Structural health monitoring (SHM) is concerned with the continuous, long-term assessment of structural integrity. One commonly investigated SHM technique uses guided ultrasonic waves, which travel through the structure and interact with damage. Measured signals are then analyzed in software for detection, estimation, and characterization of damage. One common configuration for such a system uses a spatially-distributed array of fixed piezoelectric transducers, which is inexpensive and can cover large areas. Typically, one or more sets of prerecorded baseline signals are measured when the stru
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8

Singh, Gurjashan. "Health Monitoring of Round Objects using Multiple Structural Health Monitoring Techniques." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/330.

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Structural Health Monitoring (SHM) techniques are widely used in a number of Non – destructive Evaluation (NDE) applications. There is a need to develop effective techniques for SHM, so that the safety and integrity of the structures can be improved. Two most widely used SHM methods for plates and rods use either the spectrum of the impedances or monitor the propagation of lamb waves. Piezoelectric wafer – active sensors (PWAS) were used for excitation and sensing. In this study, surface response to excitation (SuRE) and Lamb wave propagation was monitored to estimate the integrity of the roun
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9

Attar, Latifa. "Evaluation par ondes guidées de niveaux d'adhésion dissymétriques dans des collages structuraux métal-matériau composite. : Modélisation et approches des cas de Kissing Bonds." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMLH06/document.

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Cette thèse s'intéresse à l'évaluation de la qualité de l'adhésion dans des assemblages structuraux métal/adhésif/composite carbone-époxy, assemblages utilisés dans l'industrie automobile et aéronautique. La qualité du collage est évaluée par méthodes non destructives grâce à des ondes guidées ultrasonores de type Lamb et SH. Un nouveau modèle numérique par éléments finis a été développé au cours de ce travail : il s'agit d'un modèle rhéologique aux interphases qui permet de tracer les courbes de dispersion des modes guidés dans les échantillons étudiés. Il permet aussi de prédire l'évolution
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10

Musio, Antonio. "Modelling and experimental implementation of infrared thermography on concrete masonry structures." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Industrialized countries have and are based on a network infrastructure is becoming increasingly complex and difficult to manage these systems, mainly due to a lack of financial resources. Asset management is a paradigm that is adopted to properly manage the infrastructure, ensuring that the available resources are properly utilized to ensure the necessary level of service to users of the infrastructure. It includes managing the entire life cycle, including design, construction, commissioning, operation, maintenance, modification, replacement or cancellation of physical infrastructure assets.
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11

Niroula, Kushal. "Acoustic Monitoring of the Main Suspension Cables of the Anthony Wayne Bridge." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1399636404.

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12

Gordon, Neal A. "Material Health Monitoring of SIC/SIC Laminated Ceramic Matrix Composites With Acoustic Emission And Electrical Resistance." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1414835900.

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13

Marques, José Roberto Franco. "Dimensionamento de reforço mediante retroanálise de avaliações estruturais não-destrutivas." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/18/18137/tde-10072017-170430/.

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A avaliação estrutural é muito importante para os sistemas de gerência de pavimentos, principalmente, para as análises em nível de projeto. Os métodos de dimensionamento de reforço em uso no Brasil, baseado apenas na deflexão recuperável máxima, não exploram todas as potencialidades das avaliações estruturais não destrutivas, pois utilizam expressões empíricas, não associadas diretamente ao comportamento mecanístico do pavimento. Este trabalho tem por objetivo analisar os métodos existentes no Brasil para o dimensionamento de reforço de pavimento flexíveis e compará-los com o dimensionamento m
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14

Kahan, Michel. "Non destructive structure evaluation : an application of seismic signal analysis." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/68276.

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15

Mong, Seng Ming. "Non-destructive evaluation with ultrasonic pulse velocity (UPV) in concrete structure." access abstract and table of contents access full-text, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21175032a.pdf.

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Thesis (M.Sc.)--City University of Hong Kong, 2005.<br>At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.
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16

Lau, Connie K. Y. "Non-destructive evaluation with ultrasonic pulse velocity (UPV) in concrete structure." access abstract and table of contents access full-text, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21174441a.pdf.

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Thesis (M.Sc.)--City University of Hong Kong, 2005.<br>At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 1, 2006) Includes bibliographical references.
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17

Evanson, S. "The evaluation of a squid based non-contact magnetic NDE technique for application to the inspection of offshore steel structures." Thesis, University of Strathclyde, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303266.

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18

PINTO, RAPHAEL PEREIRA. "NON-DESTRUCTIVE, MICROSTRUCTURAL AND MECHANICAL PERFORMANCE EVALUATION OF METAL POLYMER HYBRID STRUCTURES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36323@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>A indústria de transporte tem enfrentado rigorosas políticas econômicas e ambientais para a redução do consumo de combustível e consequentemente redução na emissão de CO2. Uma solução promissora para suprir tais exigências encontra-se na redução do peso da estrutura de carros e aviões através do uso de estruturas híbridas. Técnicas de união convencionais geralmente são inadequadas para produzir juntas híbridas de metal e polímero. Sendo assim, tecnologias de junção inovadoras
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19

Tan, Hock Chuan. "Load-induced damage evaluation in reinforced concrete structures using dynamic response signatures." Thesis, University of Aberdeen, 2000. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602019.

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The purpose of this thesis is to assess and develop a non-destructive evaluation (NDE) procedure for evaluating the integrity of rectangular and square reinforced concrete (RC) slabs. This procedure employs both dynamic frequency and deformation response signatures to track changes in the slab following dynamic excitation. Such a procedure could provide a good basis for practising engineers to conduct nondestructive testing (NDT) and evaluation of general RC structures. The response of RC floor slabs to dynamic excitation have been experimentally studied at 1/3rd scale for two aspect ratios (s
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20

Cung, Thành Long. "Évaluation non-destructive quantitative de structures aéronautiques par la méthode des courants de Foucault." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2012. http://tel.archives-ouvertes.fr/tel-00749648.

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La méthode des courants de Foucault (CF) est très largement utilisée en milieu industriel pour l'évaluation non destructive (END) de pièces ou de structures électriquement conductrices, parce qu'elle est sensible, robuste peu couteuse et non polluante. Toutefois, dans le cas général, l'évaluation quantitative des paramètres caractéristiques d'une structure est un problème difficile, d'une part parce que les données CF disponibles sont généralement incomplètes, d'autre part parce qu'il est nécessaire de faire appel à des modèle numériques élaborés pour rendre compte des interactions sonde / str
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21

Yoho, Jason Jon III. "Design and Calibration of a RF Capacitance Probe for Non-Destructive Evaluation of Civil Structures." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/9756.

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Portland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. Non-destructive evaluation (NDE) methods are potentially among the most useful techniques developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concr
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22

Watase, Azusa. "Non-Destructive Evaluation of Concrete Structures Using High Resolution Digital Image and Infrared Thermography Technology." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5885.

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As existing bridge structures age, they are susceptible to the effects of deterioration, damage and other deleterious processes. These effects hamper the capacity and efficiency of transportation networks and adversely impact local, regional and national economic growth. As a result, bridge authorities and other professionals have become more sensitive to maintenance issues related to this aging infrastructure. While highway bridge condition have been monitored by visual inspection, non-destructive evaluation (NDE) technologies have also been developing and they are expected to be utilized for
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23

Todd, Charles Peter Debenham. "Non-destructive evaluation of adhesively bonded structures using ultrasonic Lamb waves and artificial neural networks." Thesis, Keele University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361828.

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24

Peng, Shuang. "Advance on Non-Destructive Evaluation methodologies for the material characterization and damage monitoring of masonry structures." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0234.

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La France est dotée d'un très large patrimoine historique en maçonnerie de pierre. La sauvegarde de ce patrimoine historique constitue un enjeu culturel et économique. Ce type d'édifice, à forte valeur architecturale, limite l'emploi d'essais destructifs. Le besoin exprimé concerne l'absence d'une méthodologie fiable pour l'évaluation des structures à l'échelle du matériau et de la structure. Cette thèse se propose donc de répondre à deux verrous : (i) comment fiabiliser l'Evaluation Non Destructive (END) des matériaux sur ouvrages, (ii) comment mieux détecter, localiser et suivre les défauts
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25

Kaltmann, Deena, and s8907403@student rmit edu au. "Quantitative Line-Scan Thermographic Evaluation of Composite Structures." RMIT University. Aerospace, Mechanical & Manufacturing Engineering, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091019.101029.

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This MEng (Master of Engineering) research thesis evaluates the capabilities and limitations of line-scan thermography for the non-destructive evaluation of composite structures containing hidden defects. In simple terms, line-scan thermography is a state-of-the-art technique in which a focused line of thermal energy is transmitted into a material. Line-scan thermography has great potential for the rapid and low cost non-destructive inspection of composite structures for aircraft, automobiles and ships. In this project, theoretical research exploring the heat transfer physics was undertaken in
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26

Nguyen, Anh Quan. "Evaluation non destructive du gradient de teneur en eau dans les structures en béton armé par résistivité électrique." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30380/document.

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Nous proposons une nouvelle procédure de mesure permettant de tracer la courbe de résistivité en fonction de l'écartement électrode de courant-électrode de potentiel relié à la profondeur d'investigation et au gradient de teneur en eau. Les mesures de résistivité au droit des armatures sont réalisées et une procédure d'inversion permettant de remonter au gradient de résistivité est mise en place. Deux types de mesures ont été effectués expérimentalement, sur des dalles en béton armé et non armée. Deux types de gradient sont étudiés : le séchage et l'humidification. La présence de l'armature di
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27

Alhajj, Marie Antoinette. "Inversion conjointe de mesures non destructives pour l'évaluation des gradients de degré de saturation dans le béton d'enrobage des structures." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0017.

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Les méthodes d’évaluation non destructives donnant accès à la mesure de la résistivité électrique et de la permittivité diélectrique sont très sensibles au degré de saturation du béton. Inversées et calibrées indépendamment, ces mesures permettent d’obtenir des profils de gradients de degré de saturation en fonction de la profondeur. Dans cette thèse, nous développons une méthode d’inversion conjointe des mesures de résistivité et de permittivité pour améliorer la fiabilité et la précision des profils de degré de saturation estimés. Nous modélisons les mesures sur une dalle de béton en 3D par
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28

Dia, Abdou. "Monitoring des câbles de structures du génie civil par combinaison de techniques vibratoires et émission acoustique." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0046.

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Les méthodes d’évaluation non destructives donnant accès à la mesure de la résistivité électrique et de la permittivité diélectrique sont très sensibles au degré de saturation du béton. Inversées et calibrées indépendamment, ces mesures permettent d’obtenir des profils de gradients de degré de saturation en fonction de la profondeur. Dans cette thèse, nous développons une méthode d’inversion conjointe des mesures de résistivité et de permittivité pour améliorer la fiabilité et la précision des profils de degré de saturation estimés. Nous modélisons les mesures sur une dalle de béton en 3D par
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29

Ghosh, Kumar Kanti. "Assessment of FRP composite strengthened reinforced concrete bridge structures at the component and systems level through progressive damage and Non-Destructive Evaluation (NDE)." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3211930.

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30

Bergmann, Jana, Hans Dörmann, and Rüdiger Lange. "Interpreting process data of wet pressing process: Part 2: Verification with real values." Sage, 2016. https://tud.qucosa.de/id/qucosa%3A35791.

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For the analysis of the wet pressing process, which was presented in the first part of this paper, a theoretical approach was chosen. This enabled the pre-definition of three quality-related priorities which now will be considered in detail in the second part. For further analysis, real process data, recorded in an early phase of the process implementation, are used. The challenge is that in this process status, the availability of data is limited or the data sets are incomplete. Supported by the theoretical approach, an easier interpretation of the process data, and in case of ambiguous issue
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31

Fontul, Simona. "Structural evaluation of flexible pavements using non-destructive tests." Doctoral thesis, 2004. http://hdl.handle.net/10316/15738.

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Tese de doutoramento em Engenharia Civil apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra<br>The aim of this work is to contribute to the improvement of the methodologies used in structural pavement evaluation, concerning in particular the backcalculation of layer moduli based on Falling Weight Deflectometer (FWD) together with Ground Penetrating Radar (GPR) test results. The main aspects that are dealt with are the application of GPR to pavement evaluation, the use of FWD data together with layer thickness data obtained from GPR and the improvement of the effic
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32

(7874897), Ryan T. Whelchel. "Evaluation and Structural Behavior of Deteriorated Precast, Prestressed Concrete Box Beams." Thesis, 2019.

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Adjacent precast, prestressed box beam bridges have a history of poor performance and have been observed to exhibit common types of deterioration including longitudinal cracking, concrete spalling, and deterioration of the concrete top flange. The nature of these types of deterioration leads to uncertainty of the extent and effect of deterioration on structural behavior. Due to limitations in previous research and understanding of the strength of deteriorated box beam bridges, conservative assumptions are being made for the assessment and load rating of these bridges. Furthermore, the desig
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33

Han, Je Heon. "Investigation on Wave Propagation Characteristics in Plates and Pipes for Identification of Structural Defect Locations." Thesis, 2013. http://hdl.handle.net/1969.1/151345.

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For successful identification of structural defects in plates and pipes, it is essential to understand structural wave propagation characteristics such as dispersion relations. Analytical approaches to identify the dispersion relations of homogeneous, simple plates and circular pipes have been investigated by many researchers. However, for plates or pipes with irregular cross-sectional configurations or multi-layered composite structures, it is almost impossible to obtain the analytical dispersion relations and associated mode shapes. In addition, full numerical modeling approaches such as
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34

Trivedi, Tanuj Kiranbhai. "Rapid reading for passive wireless coupled sensors." Thesis, 2012. http://hdl.handle.net/2152/ETD-UT-2012-08-6201.

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The objective of this thesis is to design and implement a rapid, reconfigurable and portable reader for wirelessly interrogating inductively coupled passive sensors. While the current method of impedance analyzer is sensitive and an accurate, the instruments used are bulky and slow, substantially hampering in-field testing and interrogation of sensors. Current methods cannot provide a quantifiable measure on minimum necessary read-speeds and instrument accuracy desirable for rapid sensing applications. This work summarizes the design and hardware implementation of two reader methods that addre
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Cheng, Shumin. "Non-destructive evaluation of cracking in tubular T-joints using vibration procedures /." 1998.

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36

Μπαλτόπουλος, Αθανάσιος. "Multifunctional composite structures with damage sensing capabilities." Thesis, 2013. http://hdl.handle.net/10889/7832.

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The scope of this thesis is to reveal, identify and investigate promising routes for developing multifunctional composite structures with damage sensing capabilities towards the development of integrated non-destructive inspection (NDI) and structural health monitoring (SHM) capabilities. Two routes were identified and selected for further investigation; the enhancement of multifunctionality of composite systems through the use of nanotechnology and the development of novel damage sensing techniques based on the electrical properties of the composites. Both were selected in the view of better
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