Το αντικείμενο της παρούσας διδακτορικής διατριβής είναι η ανάπτυξη μιας εναλλακτικής μεθόδου μη καταστροφικού ελέγχου (ΜΚΕ) για αγώγιμα υλικά, που συνδυάζει την ηλεκτρομαγνητική διέγερση - επαγωγική θέρμανση του υλικού και επιθεώρηση με μεταβατική υπέρυθρη θερμογραφία. Με ένα μεταβαλλόμενο μαγνητικό πεδίο επάγονται δινορρεύματα εντός του εξεταζόμενου δοκιμίου. Η θερμότητα που παράγεται από τα δινορρεύματα, δημιουργεί θερμοκρασιακές διαφορές οι οποίες τείνουν να εξομαλυνθούν μέσω της θερμικής αγωγής. Κάποια ατέλεια στη δομή του υλικού, όπως είναι μια ρωγμή, θα επηρεάσει άμεσα ή έμμεσα τη ροή της θερμότητας και κατ’ επέκταση τη θερμοκρασιακή κατανομή στην επιφάνεια του υλικού. Χρησιμοποιώντας την υπέρυθρη θερμογραφία μπορούμε να απεικονίσουμε σε δύο διαστάσεις τη θερμοκρασιακή κατανομή της επιφάνειας του επιθεωρούμενου δοκιμίου και να εντοπίσουμε την ατέλεια αυτή. Η παρούσα διατριβή επικεντρώνεται στην υπολογιστική και πειραματική διερεύνηση της αποτελεσματικότητας και της αξιοπιστίας της ηλεκτρομαγνητοθερμικής μεθόδου ως μεθόδου ΜΚΕ σε αγώγιμα υλικά. Αφού πραγματοποιηθεί αναλυτική περιγραφή του μοντέλου με το οποίο προσεγγίζονται τα ηλεκτρομαγνητικά - θερμικά φαινόμενα της ηλεκτρομαγνητικής διέγερσης - επαγωγικής θέρμανσης αγώγιμων υλικών, αναπτύσσεται υπολογιστικός κώδικας για την υλοποίηση του μοντέλου. Με τη χρήση του υπολογιστικού προγράμματος διερευνάται η σημασία και η σπουδαιότητα ενός μεγάλου πλήθους παραμέτρων που επηρεάζουν την αποτελεσματικότητα της ηλεκτρομαγνητοθερμικής μεθόδου με απώτερο στόχο τη βελτιστοποίηση της. Στη συνέχεια ακολουθεί πειραματική επαλήθευση των αριθμητικών αποτελεσμάτων, όπου και αποδεικνύεται η αξιοπιστία των υπολογιστικών μοντέλων που χρησιμοποιήσαμε κατά την αριθμητική διερεύνηση της μεθόδου. Κατ’ αυτόν τον τρόπο επαληθεύεται η αποτελεσματικότητα της μεθόδου στον ΜΚΕ έλεγχο αγώγιμων υλικών. Το γενικό συμπέρασμα που προκύπτει είναι ότι η ηλεκτρομαγνητοθερμική μέθοδος αποτελεί μια αξιόπιστη μέθοδο για τον ΜΚΕ αγώγιμων υλικών. Απομένει πλέον να διερευνηθούν οι δυνατότητες της μεθόδου στο έπακρο, ώστε να αναδειχθεί το εύρος των εφαρμογών αυτής και να χρησιμοποιηθεί ενδεχομένως σε περιπτώσεις όπου μέχρι σήμερα κυριαρχούν άλλες διαγνωστικές μέθοδοι. / The subject matter of the present dissertation is the development of an alternative method for non-destructive inspection of conducting materials, which combines electromagnetic excitation – thermal conduction and inspection with transient infrared thermography. A time-varying magnetic field is used to induce eddy currents inside the conducting material under inspection. The Ohmic power generated in the material by the eddy currents creates temperature gradients which tend to be ironed out through thermal conduction. A defect in the material structure, such as a cracking, will affect the heat flow either directly or indirectly and hence the temperature distribution at the surface of the material. By employing infrared thermography, it is then possible to visualize in two-dimensional the temperature distribution over the excited surface of the tested specimen and detect the defect. The present dissertation focuses on computational and experimental investigation of the effectiveness and reliability of electromagnetic-thermal method as a method for non destructive inspection of conductive materials. After have been made a detailed description of the model which describes the electromagnetic-thermal phenomena of electromagnetic excitation - induction heating in conductive materials, it was developed a computer program based on the above model. Using the computer program we investigated the significance and the importance of a large number of parameters affecting the effectiveness of electromagnetic-thermal method, with a view to optimize the method. The experimental verification of numerical results, indicate the reliability of computational model used in the numerical investigation of the method and verifies the method’s effectiveness for non destructive inspection of conducting materials. The general conclusion is that the electromagnetic - thermal method is a reliable method for non destructive inspection of conductive materials. It remains the full potentials of the method to be investigated, in order to extend the range of applications and use the method in cases where today dominate other diagnostic methods.

CAPES / A detecção de defeitos de soldagem em imagens radiográficas visa garantir a segurança das estruturas em análise com o objetivo de evitar perdas financeiras e prevenir contra danos ambientais. Atualmente, a inspeção de juntas soldadas é uma atividade essencialmente humana e, portanto, está sujeita a erros relacionados à acuidade visual, à experiência, à fadiga e às distrações do inspetor, afetando a repetitividade e reprodutibilidade deste processo. Nesse sentido, este trabalho apresenta um método para auxiliar na detecção de defeitos em juntas soldadas de tubulações de petróleo, utilizando radiografias computadorizadas adquiridas pela técnica de exposição Parede Dupla Vista Dupla (PDVD). O método desenvolvido compreendeu a aplicação do realce das imagens tratadas, a segmentação de descontinuidades e a redução do espaço de busca pela eliminação da região central da junta soldada PDVD. Dessa maneira, os referidos procedimentos contribuíram para que as descontinuidades segmentadas que correspondiam a regiões de defeito em potencial fossem classificadas por Redes Neurais Artificiais (RNA) Multilayer Perceptron (MLP), realizando a detecção de defeitos de soldagem. / Detection of weld defects in radiographic images aims to ensure the safety of analyzed structures in order to avoiding financial losses and prevent against environmental damage. Nowadays, the inspection of welded joints is essentially a human activity and, therefore, it is subject to errors related to the inspector visual acuity, experience, fatigue and distractions, affecting the repeatability and reproducibility of this process. In this sense, this work presents a method to assist the detection of weld defects in welded joints of petroleum pipelines in computed radiography acquired by Double Wall Double Image (DWDI) technique. The developed method involved the application of contrast enhancement of treated images, segmentation of discontinuities and, the search space reduction by eliminating the central region of the DWDI weld. Thus, these procedures contributed to that segmented discontinuities which correspond to potential weld defects regions were classified by Multilayer Perceptron Neural Networks, performing the detection of weld defects.

CNPQ; LASCA / Este trabalho propõe um algoritmo para identificar descontinuidades internas em uma peça metálica a partir de sinais A-scan provenientes de um ensaio não-destrutivo por ultrassom. As descontinuidades são identificadas por seu formato, dimensões, orientação e localização. Esse algoritmo é baseado na resolução de problemas inversos. O problema da identificação de descontinuidades é modelado utilizando uma abordagem inédita, em que a descontinuidade é caracterizada por dois elementos distintos: a sua amplitude de espalhamento e a localização de seu centro. Com essa nova forma de representação, o problema de identificação da descontinuidade passa a ser dividido em dois subproblemas. O primeiro é o problema de reconstrução para encontrar a localização do centro da descontinuidade e o segundo é o problema de caracterização para estimar os parâmetros geométricos da descontinuidade. Os ensaios realizados comprovam que o problema de localização é resolvido de forma satisfatória utilizando o algoritmo de reconstrução de imagens esparsas UTSR (ultrasonic sparse reconstruction). A caracterização da descontinuidade é realizada por um algoritmo baseado no método dos mínimos quadrados não-lineares, com a inclusão de um termo de regularização não-quadrático utilizando norma l1. Os resultados obtidos tanto com dados simulados como com dados experimentais mostram que esse algoritmo estima as descontinuidades de forma satisfatória. / The present work proposes an algorithm to identify internal discontinuities in metallic specimen from A-scan ultrasonic signals. Discontinuities are identified by their shape, size, orientation and location. This algorithm is based on inverse problems. The identification of discontinuities is modeled using a novel approach. The discontinuity is modeled by two distinct elements: its scattering amplitude and its center location. Through this approach, the identification problem is split into two sub problems. The first is a reconstruction problem to find the location of the discontinuity. The second is a model identification problem to estimate geometric parameters of the discontinuity. Simulations and experimental validation show that the localization problem is satisfactorily solved using the UTSR (ultrasonic sparse reconstruction) algorithm. The characterization of discontinuities is carried out by an algorithm based on non-linear least squares with l1 norm regularization. The results obtained with simulated data as well with experimental data show a fine estimation of discontinuities.

Summaries in Afrikaans and English / The goal of this study is to understand the phenomenon of self mutilation by adolescents, with whom there is no developmental or mental barrier, from an educational-psychological perspective. A literature study was undertaken to investigate the nature, classification, causes and treatment of self mutilation, as well as the Educational Psychological Relations Theory. The self mutilation of adolescents was placed within the Educational Psychological Relations Theory framework. The research results showed that selfmutilation, with adolescents with whom there is no developmental or mental barrier, is a symptom of disharmonic intra- and interpsychic processes, as it is understood within the Educational Psychological Relations Theory. Self mutilation is used as a coping mechanism to regulate unpleasant emotional experiences. The empirical study also showed that an impoverished educational climate contributes to the development of self mutilation by adolescents. / Die doel van hierdie studie is om die verskynsel van selfmutilering by adolessente, by wie daar nie ontwikkelings- of geestesgestremdheid aanwesig is nie, vanuit 'n opvoedkundig-sielkundige perspektief te verstaan. Aan die hand van die literatuurstudie is die aard, klassifisering, oorsake en behandeling van selfmutilering, asook die Opvoedkundig-Sielkundige Relasieteorie verken. Die Opvoedkundig-Sielkundige Relasieteorie is as raamwerk gebruik waarbinne die verskynsel van selfmutilering by adolessente ondersoek is. Die navorsingsresultate het aan die lig gebring dat selfmutilering, by adolessente by wie daar nie geestes- of ontwikkelingsgestremdheid teenwoordig is nie, 'n simptoom is van disharmoniese intra- en interpsigiese gebeure soos dit verstaan word binne die Opvoedkundig-Sielkundige Relasieteorie. Selfmutilering word gebruik as 'n verdedigingsmeganisme waarmee onaangename belewinge gereguleer word. Die empiriese studie het ook getoon dat 'n onbevredigende opvoedingsklimaat 'n groot bydrae lewer tot die ontwikkeling van selfmutilering by adolessente. / Educational Studies / M. Ed. (with specialiation in Guidance and Counseling)

Tidigare studier har visat på att i varje missbrukares liv, finns cirka fem anhöriga som riskerar att utveckla medberoende. Riskfaktorerna associerade med medberoende påverkar därför förekomsten av psykiska ohälsa och ökar risken för att utveckla andra sjukdomar såsom depression, ångest och känslomässiga problem. Syftet med studien var att undersöka hur medberoende i nära relationer kan utveckla självdestruktivt beteende och psykisk ohälsa. Med hjälp av en kvalitativ metod och intervjuer som datainsamlingsmetod blev syftet med denna studie genomförd. Studien grundades på semistrukturerade intervjuer där totalt sex informanter deltog. Resultatet i studien visade på liknande resultat genom alla intervjuer, såsom förekomsten av psykiska sjukdomar, självdestruktivt beteende och vikten av introjektiv identifikation. Dessa tre kategorier kompletterar varandra i den skrivna ordningen. Resultatet tyder på att det kan vara så att den medberoende inte kan utveckla psykisk ohälsa utan fenomenet introjektiv identifikation och självdestruktivt beteende. För att det ska utvecklas någon form av psykisk ohälsa skulle den medberoende personen behöva utveckla ett självdestruktivt beteende, och resultatet tyder på att det inte är möjligt utan introjektiv identifiering i kontexten nära relationer. Dock med hjälp av anknytningsteorin och coping-strategin, visade slutsatsen att inte alla medberoende utvecklade psykisk ohälsa. Förekomsten av psykisk ohälsa påverkas av individens tidiga anknytningsmönster och copingförmåga. Studien ledde till slutsatsen att psykisk ohälsa är ett stort problem bland individer med medberoende. Medberoende är inte fastställt som en sjukdom, trots att risken för att eventuellt utveckla psykisk ohälsa finns. Trots de följdsjukdomar som medberoende medför är det ingen prioritering inom folkhälsopolitiken. / Previous studies have shown that in every drug addicted person’s life there is about five relatives which risks developing co-dependency. Therefore, the riskfactors affect the relative’s mental health and increase the risk of developing other illnesses such as depression, anxiety and emotional issues. The aim of the study was to investigate how co-dependency in close relationships can develop self-destructive behavior and mental illness. With the use of a qualitative method and interviews as a data collecting method, the aim for this study became fulfilled. The study was based on semi-structured interviews, performed by six participants. The results showed similar outcomes for all interviews, such as the prevalence for mental illness, self-destructive behaviour and the importance of introjective identification. These three categories complement each other in the order written. The results indicates that a co-dependent individual could not, without the phenomenon introjective identification and self-destructive behaviour acquire mental illness. However in order to acquire some kind of mental illness the co-dependent person would have to develop self-destructive behaviour, and the results showed that it is not possible without introjective identification in the context of a close relationship. Although, with the use of attachment theory and coping-strategy, the conclusion showed that not every co-dependent developed mental illness. The prevalence of illnesses was affected by the individuals early life attachment-pattern and coping skills. The study led to a conclusion that mental illness is a big issue among co-dependent individuals. Co-dependency is not a determined as a disease, despite the risk of possibly developing mental illness. It is still not a prioritization among public health authorities.

Ces dernières années, les modes de Lamb à vitesse de groupe nulle (ZGV) se sont révélés être un outil efficace pour sonder localement et précisément l'épaisseur d'un échantillon ou les propriétés mécaniques de matériaux isotropes ou anisotropes. Ce type particulier d'ondes guidées, telles de fortes résonances locales de la structure, résulte de l'interférence de deux ondes de Lamb ayant une vitesse de phase opposée et coexistant pour un couple fréquence-nombre d'ondes particulier. Les ultrasons laser ont démontré leur capacité à générer et détecter efficacement de telles résonances locales dans la gamme des MHz. En effet, la configuration tout optique, constituée d'une source laser pulsée pour générer les ondes élastiques et d'un interféromètre pour sonder le déplacement normal associé, évite tout contact avec l'échantillon, limitant ainsi l'élargissement ou la suppression de résonances. L'utilisation de modes ZGV pour suivre la fatigue des matériaux et sonder des phénomènes non linéaires reste cependant un défi et constitue le cœur des travaux de recherche présentés ici. La partie théorique porte sur la compréhension de l’effet de la fatigue mécanique sur les modes ZGV à travers l’analyse fréquence-nombre d’ondes des modes de Lamb. La partie expérimentale est consacrée à l’application de cette technique pour l'ECND et le suivi de la fatigue de plaques métalliques minces. Les modes ZGV en ultrasons laser montrent un grand potentiel pour localiser les dommages dus à la fatigue, prédire la vie en fatigue et évaluer qualitativement, voire quantitativement, les différents stades de dommages causés par la fatigue. / In recent years, zero-group-velocity (ZGV) Lamb modes have proven to be an efficient tool to probe locally and very accurately the thickness of a sample or the mechanical properties of either isotropic or anisotropic materials. This particular type of guided waves, corresponding to sharp local resonances of the structure, results of the interference of two Lamb waves having opposite phase velocity and coexisting at a couple given frequency-wavenumber. The laser ultrasonic technique has demonstrated its ability to efficiently generate and detect such local resonances within the MHz frequency range. Indeed, the all-optical setup, consisting of a pulsed laser source to generate elastic waves and of an interferometer to probe the associated normal displacement, avoids any contact with the sample, hence limiting the broadening or suppression of the resonances. Yet, the use of ZGV Lamb modes to monitor material fatigue and to probe nonlinear phenomena remains challenging and is the core of the here-reported research. The theoretical part of this PhD research deals with the understanding of the effect of mechanical fatigue on ZGV Lamb modes through the frequency-wavenumber analyzes of the Lamb waves. The experimental part of the PhD research is dedicated to the application of this technique for the nondestructive characterization and for the monitoring of mechanical and thermal fatigue of thin metal plates. Zero-group-velocity Lamb modes in laser ultrasonics shows great promises to locate fatigue damage, to predict the fatigue lifetime, and to qualitatively, and even quantitatively, assess the different stages of fatigue damage in   m- to potentially cm-thick solid plates.

Text in Afrikaans / Sekere bevindings oor die positiewe en negatiewe invloed van musiek en die funksies wat dit met betrekking tot menswees vervul, is as 'n verwysingsraamwerk gebruik om historiese gegewens oar die konstruktiewe en destruktiewe aanwending van musiek in hoofsaaklik Duitsland en die V.S.A. te analiseer. Dit het aan die lig gekom dat musiek konstruktief aangewend is met betrekking tot: Intellektuele vorming: Intellektuele vaardighede en kennisverwerwing is deur musiek bevorder. Die leergebeure is veraangenaam en meer effektief gemaak. Estetiese vorming: Deur musiek is 'n estetiese waardesisteem en 'n goeie kunssmaak ontwikkel en die wording van volwaardige, gebalanseerde individue bevorder. Religieuse vorming: Musiek is aangewend om religieuse denke en gewaarwordinge uit te druk en om kennisoordrag, evangelisasie, sending en die belewing van 'n innige geloofsgemeenskap te bevorder. Etiese vorming: Etiese waarhede is met behulp van musiek herhaal en ingeoefen. 'n "Morele atmosfeer" en die vaslegging van 'n waardesisteem is daardeur bevorder. Politieke vorming: Politieke gevoelens en menings is deur musiek uitgedruk om mense te be1nvloed om bepaalde standpunte, partye, regerings of politieke stelsels te ondersteun. Nasionale vorming: Musiek is gebruik om patriotisme te verwoord, die kulture van volkere te weerspieel, volksfeeste op te luister en nasionale eenheid te bevorder. Sosiale vorming: Musiek is aangewend as 'n bran van vermaak en ontspanning en as 'n kommunikasiemiddel. Dit het gehelp om 'n groepsidentiteit te vestig, 'n gemeenskapsgevoel en sosialisering te bevorder en mense se gedragspatrone te be1nvloed. Affektiewe vorming: Deur middel van musiek is gepoog om die gevoelslewe te orden en te veredel en om positiewe veranderinge ten opsigte van affektiewe toestande teweeg te bring. Fisieke vorming: Verskeie liggaamsaktiwiteite en fisieke vaardighede, ontspanning en verfrissing is deur musiek bevorder en dit is as 'n terapie aangewend. Musiek is oak destruktief aangewend deurdat die Christelike kerk ondermyn, religieuse aanbidding benadeel, die jeug se emosionele beheer, selfstandigwording en etiese waardestelsels negatief be!nvloed, aggressiewe en opstandige gedrag, militarisme, politieke venyn en rassehaat bevorder, beswyming ge!nduseer, gehoorsintuie beskadig en regerings omvergewerp is. 'n Aantal aanbevelings en waarskuwings met betrekking tot die aanwending van musiek in formele, nieformele en informele onderwys- en opvoedingsituasies het uit die analise voortgevloei. / Certain findings concerning the positive and negative influences of music and the functions fulfilled by it in the life-world of man were used as a reference framework in order to analyse historical data on the constructive and destructive applications of music in mainly Germany and the U.S.A. It came to light that music was constructively applied with regard to: Intellectual shaping: Music was employed to enhance various intellectual skills, to improve the acquisition of knowledge and to render the learning process more pleasant and effective. Aesthetic shaping: An aesthetic value system and a good artistic taste were developed and the shaping of complete, balanced individuals was promoted through music. Religious shaping: Music was employed to express religious thoughts and perceptions and to promote close community of faith, knowledge transfer, evangelization and missionary effort. Ethical shaping: Ethical truths were reiterated and "practised" and a "moral atmosphere" and a value system established through music. Political shaping: Political feelings and opinions were expressed through music and people were influenced to support specific viewpoints, parties, governments or political systems. National shaping: Music was employed to express patriotism, to reflect the cultures of nations, to add lustre to national gatherings and to promote national unity. Social shaping: Music was a source of entertainment and recreation and a means of communication. Through music the establishment of a group identity, socialization and a communal sense were promoted and behavioural patterns affected. Affective shaping: Music was a means of ordering and ennobling inner life and of facilitating positive changes in affective conditions. Physical shaping: Relaxation, recreation, physical skills and activities were promoted through music which was utilized as a therapy. Music was also destructively employed by undermining the Christian church and harming religious worship, by negatively influencing youth's emotional selfcontrol, ethical value systems and the actualization of independence, by furthering aggressive and rebellious behaviour, inducing trances, causing physical damage to hearing organs and promoting militarism, political viciousness, racial hatred and the overthrow of governments. A number of recommendations and warnings concerning the employment of music in formal, non-formal and informal educational situations resulted from the analysis. / Art History, Visual Arts and Musicology / D. Ed. (Historiese Opvoedkunde)

Les enceintes de confinement des centrales nucléaires sont conçues pour assurer des propriétés de confinement et d'étanchéité précises en situations d'usage normal et en cas d'accident nucléaire, afin d'éviter la dissémination de radioéléments dans l'environnement. Ces enceintes étant construites en béton, la maîtrise de l'évaluation de la perméabilité du béton et de ses évolutions sous contraintes permettrait d'évaluer les débits de fuite susceptibles d'intervenir dans le temps sous certaines sollicitations. Jusqu'aujourd'hui, il existe plusieurs techniques de mesure de la perméabilité et ces techniques aboutissent à des résultats différents pour une même éprouvette de béton. La première étude que nous avons réalisée a été donc de proposer une normalisation de la mesure de la perméabilité : cette normalisation a abouti à la détermination d'une perméabilité caractéristique du béton et indépendante de la technique de mesure. Parallèlement à cette démarche, nous avons aussi proposé d'évaluer la perméabilité du béton à l'aide d'observables du Contrôle Non Destructif comme la permittivité et la résistivité électrique. Les résultats obtenus montrent la possibilité d'estimer la perméabilité dans les conditions du béton sur site. La deuxième étude réalisée est relative à la maîtrise de la perméabilité sous contraintes. Au laboratoire, nous avons étudié la perméabilité d'éprouvettes en béton de différentes tailles dans diverses conditions de séchage, de sollicitation thermique, d'endommagements mécanique et couplés. Nous avons ainsi pu établir des modèles perméabilité-endommagements en fonction de chaque source d'endommagement. La troisième étude réalisé porte sur la transposition des résultats de laboratoire au site, à travers l'utilisation de maquette d'enceinte nucléaire de dimensions plus importantes et représentatives de l'ouvrage réel (VeRCoRs à l'échelle 1/3). L'ensemble des résultats des deux premières études ont été mise à contribution et ont permis d'aboutir à des calculs des débits de fuite et des Temps d'Etablissement du Régime Permanent d'Ecoulement cohérents avec les hypothèses de calculs. / The building reactor of the nuclear power plants are designed to provide precise containment and sealing properties in normal use situations and in the event of a nuclear accident, to prevent the spread of radioelements in the environment. Since these enclosures are made of concrete, controlling the evaluation of the permeability of concrete and its evolutions under stress would make it possible to evaluate the leakage rates that may occur over time under certain conditions. Until today, there are several techniques for measuring permeability and these techniques lead to different results for the same concrete specimen. The first study we carried out was therefore to propose a standardization of the permeability measurement: this standardization resulted in the determination of a characteristic permeability of concrete and independent of the measurement technique. In parallel with this approach, we also proposed to evaluate the permeability of concrete using observables from Non-Destructive Testing such as permittivity and electrical resistivity. The results obtained show the possibility of estimating the permeability under concrete conditions on site. The second study carried out relates to the control of the permeability under constraints. In the laboratory, we investigated the permeability of concrete specimens of different sizes under various conditions of drying, thermal stress, mechanical and coupled damage. We could establish permeability-damage models according to each source of damage. The third study carried out relates to the transposition from laboratory results to the site, using nuclear power plants mock-up of larger dimensions and representative of the actual structure (VeRCoRs at scale 1/3). All the results of the first two studies have been used and have led to calculations of leak rates and Time to Reach Steady State (TRSS) consistent with the calculation assumptions.

Made available in DSpace on 2016-12-23T13:51:48Z (GMT). No. of bitstreams: 1 Rafael Amorim Rosa.pdf: 6622589 bytes, checksum: e040fc81e3368d400ce9a5c89180edbd (MD5) Previous issue date: 2013-07-30 / Este trabalho teve como objetivos verificar as propriedades tecnológicas dos bambus Dendrocalamus gigateus e Bambusa vulgaris; avaliar as propriedades físicas e mecânicas dos bambus laminados colados (BLC) de acordo com as espécies, os adesivos e os tratamentos preservativos utilizados e; correlacionar tanto o módulo de ruptura MOR quanto o módulo de elasticidade MOE dos BLCs obtidos por meio dos métodos não destrutivos com o método destrutivo. Para isto, foram produzidas taliscas com dimensões de 0,5 x 3,0 x 70,0 cm (espessura x largura x comprimento) com os bambus das espécies D. gigateus e B.vulgaris com idade superior a três. Uma parte destas taliscas foi imersa em água e a outra em Timbor, com duração de 15 dias para ambos os tratamentos. Os adesivos utilizados foram à base de emulsão de isocianato polimérico (EPI); melamina ureia formaldeído - MUF; acetato de polivinílico cross PVAc e resorcinol formaldeído - RF. Os métodos não destrutivos utilizados para estimar o módulo de elasticidade dos BLCs foram o Stress Wave - SW, vibração longitudinal - vib. long. e vibração transversal - vib. trans. Observou-se que, os BLCs confeccionados com B. vulgaris demonstraram maior instabilidade dimensional que aqueles produzidos com o D. giganteus. Entretanto, os adesivos MUF e RF conferiram maior estabilidade dimensional aos BLCs produzidos com ambas as espécies. Tanto os BLCs de D. giganteus quanto o de B. vulgaris em relação aos dois tratamentos preservativos utilizados, tiveram a menor média de falhas no bambu quando aderidos com EPI e PVA. Para os BLCs produzidos com o bambu gigante, o Stress Wave demonstrou não ser indicado para estimar o módulo de elasticidade para os aderidos com EPI, MUF, PVA e RF. Os métodos de vib. long. e vib. trans. demonstraram boa possibilidade da estimação do MOE para os BLCs de D. giganteus para qualquer adesivo. Para os métodos não destrutivos realizados com os BLCs do bambu vulgar, a técnica do Stress Wave demonstrou ser indicado para os BLCs aderidos com MUF e com PVA. No método de vib. long. os BLCs B. vulgaris aderidos com MUF, PVA e RF tiveram alto erro de estimação. Já o método de vib. trans., proporcionou alto coeficiente de correlação de Pearson (R²), demonstrando ser o mais recomendado. O método de vib. trans. mostrou ser o melhor na estimação do módulo de elasticidade tanto para os BLCs confeccionados com D. giganteus quanto para os de B. vulgaris, proporcionando os menores erros e os maiores R². Em função dos resultados físicos e mecânicos obtidos, pode-se afirmar que os BLCs confeccionados tanto com a espécie de D. giganteus quanto de B. vulgaris podem ser indicados para a produção de móveis / This study aimed to verify the technological properties of the Dendrocalamus giganteus and Bambusa vulgaris bamboo; evaluate the physical and mechanical properties of glued laminated bamboo (BLC) according to the species, the adhesives and the preservant treatments; correlate both the module break and the modulus of elasticity - MOE of BLCs obtained by means of nondestructive methods with destructive method.. For this, were produced bamboo slivers with dimensions 0,5 x 3,0 x 70,0 cm (thickness, width and lenght) with B.vulgaris and D. giganteus species over three years old. One of these bamboo slivers were immersed in water and the other part in Timbor, lasting 15 days for both treatments. The adhesives used were based emulsion polymer isocyanate (EPI), melamine urea formaldehyde (MUF); cross polyvinyl acetate (PVAc) and resorcinol formaldehyde (RF). The non-destructive methods were used Stress Wave (SW), longitudinal vibration (vib. long.) and transverse vibration (vib. trans.). It was observed that the BLCs made from B. vulgaris demonstrated greater dimensional instability than those produced with the D. giganteus. However, MUF adhesive and RF conferred greater dimensional stability for the BLCs produced with both species. Both BLCs D. giganteus and B. vulgaris in relation to the two treatments had the lowest average failure in bamboo bonded with EPI and PVA. For BLCs produced from D. giganteus bamboo, the Stress Wave method proved not to be suitable for estimating the elastic modulus to BLCs adhered with EPI, MUF, PVA and RF. The vib. Long. and vib. trans. Methods demonstrated good possibility of estimating the MOE for BLCs of D. giganteus for any adhesive. For non-destructive methods performed with BLCs B. vulgaris bamboo, Stress Wave technique proved to be suitable for the BLCs bonded with MUF and PVA. In the vib. Long. Method, the BLCs made from B. vulgaris and bonded with MUF, PVA and RF had high estimation error. Already vib.trans.method provided high coefficient of Pearson correlation (R²), proving to be the most recommended. The vib.trans.method proved to be the best in the estimation of the modulus of elasticity for both BLCs made from D. giganteus and B. vulgaris, providing the smallest errors and the highest R². According to the physical and mechanical results obtained, it can be affirmed that BLCs made with both the species of D. giganteus or B. vulgaris may be employed for the furniture production

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nesta pesquisa utilizou-se um equipamento experimental que utiliza o método do eco-impacto produzido no Laboratório de Ensaios Físicos do Instituto Politécnico do Rio de Janeiro (UERJ/IPRJ), para estimar a espessuras de placas de concreto através da propagação de ondas de tensão geradas por um impacto. Para determinação dessa espessura, foram investigados vários mecanismos de estruturação do protótipo do equipamento com objetivo de se obter a melhor leitura possível, por meio das literaturas existentes. Entre parâmetros avaliados no estudo, estava o modelo de sensor a ser utilizado, o tipo de impactor, a precisão relacionada à aquisição de dados e o tratamento do mesmo, a distância entre o ponto de impacto e o transdutor (sensor), e o local de teste. Os resultados experimentais concordam com as previsões teóricas e revelam que este método é eficiente para análise de estrutura de concreto. A análise da espessura e resposta em frequência de um novo protótipo desenvolvido e os testes realizados possibilitou um erro médio de espessura real para amostras sem agregados de 0,39% e para as amostras com agregados com de 0,64%. Esses resultados apontam que o equipamento produzido tem potencial e que o mesmo pode ser utilizado para avaliação de estrutura de concreto. / In this research we used an experimental device that uses the method of impact-echo on Physical Testing Laboratory of the Polytechnic Institute of Rio de Janeiro (UERJ/IPRJ), to estimate the thickness of concrete slabs through the propagation of stress waves generated by an impact. To determine this thickness, several mechanisms for structuring the prototype equipment in order to obtain the best possible reading by means of existing literatures were investigated. Among the parameters evaluated in the study was the model of sensor being used, the type of impact, the precision related to the data acquisition and processing thereof, the distance between the impact point and the transducer (sensor), and test site. The experimental results agree with the theoretical predictions and show that this method is effective for analyzing concrete structure. The thickness analysis and frequency response of a new prototype and testing allowed an average error of actual thickness for samples without aggregates and 0.39 % for samples with aggregates with 0.64 %. These results indicate that the product produced has potential and that it can be used for evaluation of concrete structure.