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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Anthropometric analysis of maxillofacial foramina in skulls of four human populations using electronic calliper and 3D laser scanning methods

Alayan, Ibrahim Abead January 2014 (has links)
This study was undertaken to identify the landmarks that would provide the most reliable and predictable indicators of the position of the supraorbital, infraorbital, mental and mandibular foramina in human skulls of Hokien, Hylam, Indian and British populations of ranging ages, which would provide clinicians with suitable modifications in technique to accommodate these variations. Measurements were taken using both electronic digital callipers and 3D laser scanning. Electronic digital calliper measurements were made to estimate how far each foramen was from specific anatomical landmarks on the skulls. An apparatus was developed to position the skulls securely so that the measurement points could be accurately identified, then an electronic digital calliper was used to measure the distance between the defined points. In addition, the same skulls were also scanned using a FastSCAN™ Polhemus Scorpion™ handheld laser scanner, and imported into 3D modelling software (FreeForm Modelling Plus™). This 3D software integrates a PHANYOM™ desktop arm and a haptic force feedback device that provides the user with a sense of touch. Accordingly, with the “Ruler” tool, the measurements between various foramina and defined anatomical landmarks were measured. Measurements made by electronic digital calliper were compared statistically with those made using the 3D scanning method, and overall there was good correlation between the two, indicating that 3D scanning could be used as an alternative method. With regard to age changes in the skulls, the ages of the Hokien and Hylam groups were known, having been recorded from death records, but the Indian and British skulls were not of known age. In a preliminary study the known age skulls were used to validate the methods of Miles (1962) and Brothwell (1981) who aged skulls using tooth wear patterns. The decision was taken to use the Brothwell chart for the assessment of age in the Indian and British skulls in the main study. For each of the four population groups, intra-population comparisons of the measurements were made between right and left sides, and between skulls of young and old individuals, also inter-population comparisons between ipsilateral measurements were made. The correlation between the obtuseness of the mandibular angle and the ipsilateral measurement from the mental foramen to the posterior border of the mandible were made on both sides of the skulls of each population group. Non-significant differences were found between the measurements on right and left sides for the skulls of all populations. There were significant differences between some ipsilateral measurements but although there were statistically significant, they were not considered to be clinically significant. There were no significant differences between ipsilateral measurements with increasing age of the skulls. Also there were weak correlations between the obtuseness of the mandibular angle and the ipsilateral measurement from the mental foramen to the posterior border of the mandible on both sides of the skulls of each population group. There were good statistically agreements between the electronic digital calliper and 3D laser scanning measurements in all groups and the two methods may be used interchangeably. However 3D scanning is a digital process and therefore the scans could be accessed remotely, either across the internet or by CD.
2

Bradford Multi-Modal Gait Database: Gateway to Using Static Measurements to Create a Dynamic Gait Signature

Alawar, Hamad M.M.A., Ugail, Hassan, Kamala, Mumtaz A., Connah, David 25 November 2014 (has links)
Yes / Aims: To create a gait database with optimum accuracy of joint rotational data and an accu-rate representation of 3D volume, and explore the potential of using the database in studying the relationship between static and dynamic features of a human’s gait. Study Design: The study collected gait samples from 38 subjects, in which they were asked to walk, run, walk to run transition, and walk with a bag. The motion capture, video, and 3d measurement data extracted was used to analyse and build a correlation between features. Place and Duration of Study: The study was conducted in the University of Bradford. With the ethical approval from the University, 38 subjects’ motion and body volumes were recorded at the motion capture studio from May 2011- February 2013. Methodology: To date, the database includes 38 subjects (5 females, 33 males) conducting walk cycles with speed and load as covariants. A correlation analysis was conducted to ex-plore the potential of using the database to study the relationship between static and dynamic features. The volumes and surface area of body segments were used as static features. Phased-weighted magnitudes extracted through a Fourier transform of the rotation temporal data of the joints from the motion capture were used as dynamic features. The Pearson correlation coefficient is used to evaluate the relationship between the two sets of data. Results: A new database was created with 38 subjects conducting four forms of gait (walk, run, walk to run, and walking with a hand bag). Each subject recording included a total of 8 samples of each form of gait, and a 3D point cloud (representing the 3D volume of the subject). Using a Pvalue (P<.05) as a criterion for statistical significance, 386 pairs of features displayed a strong relationship. Conclusion: A novel database available to the scientific community has been created. The database can be used as an ideal benchmark to apply gait recognition techniques, and based on the correlation analysis, can offer a detailed perspective of the dynamics of gait and its relationship to volume. Further research in the relationship between static and dynamic features can contribute to the field of biomechanical analysis, use of biometrics in forensic applications, and 3D virtual walk simulation.
3

Extraction of Structural Component Geometries in Point Clouds of Metal Buildings

Smith, Alan Glynn 28 January 2021 (has links)
Digital models are essential to quantifying the behavior of structural systems. In many cases, the creation of these models involves manual measurements taken in the field, followed by a manual creation of this model using these measurements. Both of these steps are time consuming and prohibitively expensive, leading to a lack of utilization of accurate models. We propose a framework built on the processing of 3D laser scanning data to partially automate the creation of these models. We focus on steel structures, as they represent a gap in current research into this field. Previous research has focused on segmentation of the point cloud data in order to extract relevant geometries. These approaches cannot easily be extended to steel structures, so we propose a novel method of processing this data with the goal of creating a full finite element model from the information extracted. Our approach sidesteps the need for segmentation by directly extracting the centerlines of structural elements. We begin by taking "slices" of the point cloud in the three principal directions. Each of these slices is flattened into an image, which allows us to take advantage of powerful image processing techniques. Within these images we use 2d convolution as a template match to isolate structural cross sections. This gives us the centroids of cross sections in the image space, which we can map back to the point cloud space as points along the centerline of the element. By fitting lines in 3d space to these points, we can determine the equations for the centerline of each element. This information could be easily passed into a finite element modeling software where the cross sections are manually defined for each line element. / Modern buildings require a digital counterpart to the physical structure for accurate analysis. Historically, these digital counterparts would be created by hand using the measurements that the building was intended to be built to. Often this is not accurate enough and the as-built system must be measured on site to capture deviations from the original plans. In these cases, a large amount of time must be invested to send personnel out into the field and take large amounts of measurements of the structure. Additionally, these "hand measurements" are prone to user error. We propose a novel method of gathering these field measurements quickly and accurately by using a technique called "laser scanning". These laser scans essentially take a 3D snapshot of the site, which contains all the geometric information of visible elements. While it is difficult to locate items such as steel beams in the 3D data, the cross sections of these structural elements are easily defined in 2D. Our method involves taking 2D slices of this 3D scan which allows us to locate the cross sections of the structural members by searching for template cross-sectional shapes. Once the cross sections have been isolated, their centers can be mapped back from the 2D slice to the 3D space as points along the centerlines of the structural elements. These centerlines represent one of the most time consuming requirements to building digital models of modern buildings, so this method could drastically reduce the total modeling time required by automating this particular step.
4

Ensaios não destrutivos aplicados à avaliação de revestimentos de argamassa. / Non-destructive testing applied to the evaluation of mortar coatings.

Israel, Marcus Coimbra 13 November 2015 (has links)
Mudanças causadas pela industrialização dos canteiros de obra geram incompatibilidades executivas entre sistemas conflitantes e ininterrupção de controles com significativa variabilidade, tal como o uso do fio de prumo para controle geométrico das estruturas de concreto, responsável por acúmulo de erros com reflexo no consumo de matérias e no aumento de defeitos em revestimentos de fachada. Como alternativa, este trabalho busca colaborar com a ampliação do uso das técnicas não destrutivas no controle preventivo e corretivo das edificações em substituição aos tradicionais ensaios destrutivos, tornando o processo mais simples e confiável, além de proporcionar uma recuperação mais rápida e econômica. Para isso, analisou - através de um estudo de caso - a aplicação da tecnologia de escaneamento 3D laser para mapear a planicidade superficial da fachada de um edifício e, de forma inédita, para quantificar o volume de argamassa por intermédio da análise dos modelos 3D gerados por softwares de mercado; e através das etapas experimentais de laboratório, campo e in situ, analisou o potencial da termografia infravermelha na identificação e no mapeamento de fissuras e descolamentos ocultos nos revestimentos de argamassa e cerâmico, aplicando abordagens de aquecimento ativa ou passiva e resfriamento natural ou forçado. Os resultados do escaneamento mostraram a viabilidade da técnica como solução para identificar com precisão as áreas críticas da fachada sobre a estrutura de concreto periférica e alvenaria e, a partir da volumetria, calcular o impacto financeiro associado às sobrespessuras de argamassa nas áreas críticas comparativamente a reduções de espessura após tratamento dessas áreas. Por fim, a termografia identificou quanto à forma, tamanho e posição os defeitos de fissura e descolamento estudados, identificou influências intrínsecas ao processo de uso da tecnologia in situ e uso de recursos do equipamento para melhor visualização dos defeitos. / Changes caused by industrialization of construction sites generate executive incompatibilities between conflicting systems and uninterrupted controls with significant variability, such as the use of a plumb line for geometric control of concrete structures, responsible for error buildup with reflection in the consumption of materials and the increase of defects on facade coatings. Alternatively, this work seeks to collaborate with the expanded use of non-destructive techniques in preventive and corrective control of buildings to replace the traditional destructive testing, making the most simple and reliable process, in addition to providing a faster and economic recovery. For this analyzed by a case study the application of 3D laser scanning technology to map the surface flatness of the facade of a building, and unprecedentedly to quantify the amount of mortar through the analysis of 3D models generated by software market; and through the experimental stages of laboratory, field and in site, examined the potential of infrared thermography in the identification and mapping of hidden cracks and detachments in mortar coatings and ceramic tile, applying active or passive heating and natural cooling or forced cooling. The results of the scan showed the technical viability as a solution to accurately identify the critical areas of the facade on the peripheral concrete structure and masonry and from the volumes, calculate the financial impact associated with extra thick grout in critical areas compared the thickness reductions after treatment of these areas. Finally, thermography identified as the shape, size and position the cleft defects and detachment studied, identified influences the use of technology in situ and use of equipment resources to better visualization of defects.
5

A tecnologia e seu lugar na metodologia de restauro: Os 3D Laser Scanning como forma de documentação arquitetônica e sua aplicação no restauro do Palacete Tereza Lara em São Paulo. / The technology and its role in the methodology of restoration: the 3d laser scanning as a form of architectural documentation and its application in the restoration of the Palacete Tereza Lara in São Paulo.

Novaes, Maria Vitoria Fischer 31 October 2018 (has links)
Essa pesquisa tem por objetivo compreender o papel da documentação arquitetônica nos processos de restauração e salvaguarda do patrimônio material, com foco no levantamento arquitetônico por 3D Laser Scanning terrestre e tendo como caso de estudo o Palacete Teresa Lara, importante exemplar de arquitetura eclética do centro de São Paulo, tombado pelo CONPRESP, que foi objeto de projeto e obras de restauração. A documentação arquitetônica mostra-se importante ferramenta para a tarefa de transmissão do patrimônio às futuras gerações. É objeto de estudo de instituições ligadas ao campo disciplinar do restauro e existe consenso de que o registro e a produção de material de levantamento auxiliam na gestão e tomadas de decisão sobre o futuro dos monumentos. Para tanto, é necessário que exista o entendimento de seus aspectos físicos e configurações espaciais, além da compreensão de aspectos intangíveis do patrimônio, como sua história, condição social e relações políticas, culturais e econômicas. A documentação, o registro e a gestão da informação não são entendidos como um fim em si mesmos, mas como ferramenta para o processo de tomada de decisão projetual de conservação, sendo parte importante das etapas de pesquisa e investigação do monumento. Dessa forma, a pesquisa apresenta os benefícios que devem ser observados e que justificam o registro apurado do patrimônio histórico e fundamenta a técnica de levantamento cadastral 3D Laser Scanning terrestre, em edificações históricas. A pesquisa ainda procura compreender o debate teórico contemporâneo, com a atualização e ampliação dos conceitos da Teoria da Restauração, de Cesare Brandi, de forma a entender a relação entre a tecnologia e a teoria, e a efetiva contribuição dos avanços técnicos na prática da Restauração. Finalmente, diante da base teórica e técnica já apresentadas, a pesquisa estuda como a tecnologia de 3D Laser Scanning para levantamento cadastral foi empregada no Palacete Teresa Lara, e quais contribuições a técnica trouxe para os procedimentos e dinâmicas inerentes à obra. / The aim of this research is to understand the role of architectural documentation in the restoration and safeguarding of material heritage, focusing on the architectural survey by 3D Terrestrial Laser Scanning, having as a case study the Palacete Teresa Lara, an important eclectic architecture sample in São Paulo, registered by CONPRESP, which was the object of project and restoration works. Architectural documentation is an important tool for the task of transmitting assets to future generations. It is the object of study of institutions related to the disciplinary field of conservation and there is a consensus that the registration and production of survey material help in the management and decision making on the future of monuments. Therefore, it is necessary to have an understanding of its physical aspects and spatial configurations, as well as the understanding of intangible aspects of heritage, such as its history, social condition and political, cultural and economic relations. Documentation, registration and information management are not understood as an end in themselves, but as a tool for the conservation decision-making process, being an important part of the research and investigation stages of the monument. In this way, the research presents the benefits that must be observed and that justify the accurate recording of the historical heritage and bases the technique of cadastral surveying 3D Terrestrial Laser Scanning, in historical buildings. The research also seeks to understand the contemporary theoretical debate, with the updating and expansion of the concepts of the Theory of Restoration, by Cesare Brandi, in order to understand the relationship between technology and theory, and the effective contribution of technical advances in Restoration practice . Finally, in view of the theoretical and technical base already presented, the research studies how the 3D Laser Scanning technology for survey was used in the Palacete Teresa Lara, and what contributions the technique brought to the procedures and dynamics inherent to the work.
6

A tecnologia e seu lugar na metodologia de restauro: Os 3D Laser Scanning como forma de documentação arquitetônica e sua aplicação no restauro do Palacete Tereza Lara em São Paulo. / The technology and its role in the methodology of restoration: the 3d laser scanning as a form of architectural documentation and its application in the restoration of the Palacete Tereza Lara in São Paulo.

Maria Vitoria Fischer Novaes 31 October 2018 (has links)
Essa pesquisa tem por objetivo compreender o papel da documentação arquitetônica nos processos de restauração e salvaguarda do patrimônio material, com foco no levantamento arquitetônico por 3D Laser Scanning terrestre e tendo como caso de estudo o Palacete Teresa Lara, importante exemplar de arquitetura eclética do centro de São Paulo, tombado pelo CONPRESP, que foi objeto de projeto e obras de restauração. A documentação arquitetônica mostra-se importante ferramenta para a tarefa de transmissão do patrimônio às futuras gerações. É objeto de estudo de instituições ligadas ao campo disciplinar do restauro e existe consenso de que o registro e a produção de material de levantamento auxiliam na gestão e tomadas de decisão sobre o futuro dos monumentos. Para tanto, é necessário que exista o entendimento de seus aspectos físicos e configurações espaciais, além da compreensão de aspectos intangíveis do patrimônio, como sua história, condição social e relações políticas, culturais e econômicas. A documentação, o registro e a gestão da informação não são entendidos como um fim em si mesmos, mas como ferramenta para o processo de tomada de decisão projetual de conservação, sendo parte importante das etapas de pesquisa e investigação do monumento. Dessa forma, a pesquisa apresenta os benefícios que devem ser observados e que justificam o registro apurado do patrimônio histórico e fundamenta a técnica de levantamento cadastral 3D Laser Scanning terrestre, em edificações históricas. A pesquisa ainda procura compreender o debate teórico contemporâneo, com a atualização e ampliação dos conceitos da Teoria da Restauração, de Cesare Brandi, de forma a entender a relação entre a tecnologia e a teoria, e a efetiva contribuição dos avanços técnicos na prática da Restauração. Finalmente, diante da base teórica e técnica já apresentadas, a pesquisa estuda como a tecnologia de 3D Laser Scanning para levantamento cadastral foi empregada no Palacete Teresa Lara, e quais contribuições a técnica trouxe para os procedimentos e dinâmicas inerentes à obra. / The aim of this research is to understand the role of architectural documentation in the restoration and safeguarding of material heritage, focusing on the architectural survey by 3D Terrestrial Laser Scanning, having as a case study the Palacete Teresa Lara, an important eclectic architecture sample in São Paulo, registered by CONPRESP, which was the object of project and restoration works. Architectural documentation is an important tool for the task of transmitting assets to future generations. It is the object of study of institutions related to the disciplinary field of conservation and there is a consensus that the registration and production of survey material help in the management and decision making on the future of monuments. Therefore, it is necessary to have an understanding of its physical aspects and spatial configurations, as well as the understanding of intangible aspects of heritage, such as its history, social condition and political, cultural and economic relations. Documentation, registration and information management are not understood as an end in themselves, but as a tool for the conservation decision-making process, being an important part of the research and investigation stages of the monument. In this way, the research presents the benefits that must be observed and that justify the accurate recording of the historical heritage and bases the technique of cadastral surveying 3D Terrestrial Laser Scanning, in historical buildings. The research also seeks to understand the contemporary theoretical debate, with the updating and expansion of the concepts of the Theory of Restoration, by Cesare Brandi, in order to understand the relationship between technology and theory, and the effective contribution of technical advances in Restoration practice . Finally, in view of the theoretical and technical base already presented, the research studies how the 3D Laser Scanning technology for survey was used in the Palacete Teresa Lara, and what contributions the technique brought to the procedures and dynamics inherent to the work.
7

Rock damage caused by underground excavation and meteorite impacts

Bäckström, Ann January 2008 (has links)
The intent of this thesis is to contribute to the understanding of the origin of fractures in rock. The man-made fracturing from engineering activities in crystalline rock as well as the fracturing induced by the natural process of meteorite impacts is studied by means of various characterization methods. In contrast to engineering induced rock fracturing, where the goal usually is to minimize rock damage, meteorite impacts cause abundant fracturing in the surrounding bedrock. In a rock mass the interactions of fractures on the microscopic scale (mm-cm scale) influence fractures on the mesoscopic scale (dm-m scale) as well as the interaction of the mesocopic fractures influencing fractures on the macroscopic scale (m-km scale). Thus, among several methods used on different scales, two characterization tools have been developed further. This investigation ranges from the investigation of micro-fracturing in ultra-brittle rock on laboratory scale to the remote sensing of fractures in large scale structures, such as meteorite impacts. On the microscopic scale, the role of fractures pre-existing to the laboratory testing is observed to affect the development of new fractures. On the mesoscopic scale, the evaluation of the geometric information from 3D-laser scanning has been further developed for the characterisation of fractures from tunnelling and to evaluate the efficiency of the tunnel blasting technique in crystalline rock. By combining information on: i) the overbreak and underbreak; ii) the orientation and visibility of blasting drillholes and; iii) the natural and blasting fractures in three dimensions; a analysis of the rock mass can be made. This analysis of the rock mass is much deeper than usually obtained in rock engineering for site characterization in relation to the blasting technique can be obtained based on the new data acquisition. Finally, the estimation of fracturing in and around two meteorite impact structures has been used to reach a deeper understanding of the relation between fracture, their water content and the electric properties of the rock mass. A correlation between electric resistivity and fracture frequency in highly fractured crystalline rock has been developed and applied to potential impact crater structures. The results presented in this thesis enables more accurate modelling of rock fractures, both supporting rock engineering design and interpretation of meteorite impact phenomena. / QC 20100709
8

Ensaios não destrutivos aplicados à avaliação de revestimentos de argamassa. / Non-destructive testing applied to the evaluation of mortar coatings.

Marcus Coimbra Israel 13 November 2015 (has links)
Mudanças causadas pela industrialização dos canteiros de obra geram incompatibilidades executivas entre sistemas conflitantes e ininterrupção de controles com significativa variabilidade, tal como o uso do fio de prumo para controle geométrico das estruturas de concreto, responsável por acúmulo de erros com reflexo no consumo de matérias e no aumento de defeitos em revestimentos de fachada. Como alternativa, este trabalho busca colaborar com a ampliação do uso das técnicas não destrutivas no controle preventivo e corretivo das edificações em substituição aos tradicionais ensaios destrutivos, tornando o processo mais simples e confiável, além de proporcionar uma recuperação mais rápida e econômica. Para isso, analisou - através de um estudo de caso - a aplicação da tecnologia de escaneamento 3D laser para mapear a planicidade superficial da fachada de um edifício e, de forma inédita, para quantificar o volume de argamassa por intermédio da análise dos modelos 3D gerados por softwares de mercado; e através das etapas experimentais de laboratório, campo e in situ, analisou o potencial da termografia infravermelha na identificação e no mapeamento de fissuras e descolamentos ocultos nos revestimentos de argamassa e cerâmico, aplicando abordagens de aquecimento ativa ou passiva e resfriamento natural ou forçado. Os resultados do escaneamento mostraram a viabilidade da técnica como solução para identificar com precisão as áreas críticas da fachada sobre a estrutura de concreto periférica e alvenaria e, a partir da volumetria, calcular o impacto financeiro associado às sobrespessuras de argamassa nas áreas críticas comparativamente a reduções de espessura após tratamento dessas áreas. Por fim, a termografia identificou quanto à forma, tamanho e posição os defeitos de fissura e descolamento estudados, identificou influências intrínsecas ao processo de uso da tecnologia in situ e uso de recursos do equipamento para melhor visualização dos defeitos. / Changes caused by industrialization of construction sites generate executive incompatibilities between conflicting systems and uninterrupted controls with significant variability, such as the use of a plumb line for geometric control of concrete structures, responsible for error buildup with reflection in the consumption of materials and the increase of defects on facade coatings. Alternatively, this work seeks to collaborate with the expanded use of non-destructive techniques in preventive and corrective control of buildings to replace the traditional destructive testing, making the most simple and reliable process, in addition to providing a faster and economic recovery. For this analyzed by a case study the application of 3D laser scanning technology to map the surface flatness of the facade of a building, and unprecedentedly to quantify the amount of mortar through the analysis of 3D models generated by software market; and through the experimental stages of laboratory, field and in site, examined the potential of infrared thermography in the identification and mapping of hidden cracks and detachments in mortar coatings and ceramic tile, applying active or passive heating and natural cooling or forced cooling. The results of the scan showed the technical viability as a solution to accurately identify the critical areas of the facade on the peripheral concrete structure and masonry and from the volumes, calculate the financial impact associated with extra thick grout in critical areas compared the thickness reductions after treatment of these areas. Finally, thermography identified as the shape, size and position the cleft defects and detachment studied, identified influences the use of technology in situ and use of equipment resources to better visualization of defects.
9

Digitální model terénu pro morfologické účely / Digital terrain model for morphological purposes

Olšovský, Vít January 2017 (has links)
The aim of the thesis is measuring a part of a Svratka’s meander by the means of the FARO focus 3D X 130 scanner and a total station. Another part of the thesis is creating 3D models from individual methods and their comparison. The acquired data is processed in the SCENE, Microstaion Power Draft V8 and Atlas DMT programmes. The accuracies of the scan registrations and the resulting differences among individual methods are evaluated.
10

Static and time-dependent mechanical behaviour of preserved archaeological wood : Case studies of the seventeenth century warship Vasa

Vorobyev, Alexey January 2017 (has links)
Wooden objects have been widely used in the history of humanity and play an important role in our cultural heritage. The preservation of such objects is of great importance and can be a challenging task. This thesis investigates the static and time-dependent mechanical behaviour of archaeological oak wood from the Vasa warship. Characterisation of mechanical properties is necessary for the formulation of a numerical model to design an improved support structure. The ship was impregnated with polyethylene glycol (PEG) for dimensional stabilisation. All elastic engineering constants of the Vasa oak have been identified and compared with those of recent oak by means of the static and dynamic testing. The experiments were done on samples with cubic geometry, which allowed obtaining all elastic constants from a single sample. The usage of cubic samples with orthotropic mechanical properties during compressive experiments was validated with finite-element simulations. The Young's moduli of the Vasa oak in all orthotropic directions were smaller than those for the recent oak. The shear moduli of Vasa oak was determined and verified with the resonant ultrasound spectroscopy. The time-dependent mechanical behaviour of the Vasa oak has been studied. Creep studies were performed in uniaxial compression on the cubic samples in all orthotropic directions. The samples loaded in the longitudinal direction were subjected to different stress levels. A stress level below 15% of the yield stress in the longitudinal direction did not result in non-linear creep with increasing creep rates within the time frame of the tests. The results of the studies in radial and tangential directions showed that creep was dominated by the effect of annual fluctuations in relative humidity and temperature. The weight changes based on annual fluctuations of relative humidity were measured for Vasa oak and recent oak. The Vasa oak showed higher variations due to an increased hygroscopicity which is the result of the impregnation with PEG. In conceiving a full-scale finite-element model of Vasa ship, not only the stress-strain relations of the material but also those of the structural joints are needed. Since the in-situ measurement of joints is not an option, a replica of a section of the ship hull was built and tested mechanically. The load-induced displacements were measured using 3D laser scanning which proved to have advantages to conventional point displacement measurements. The mechanical characteristics of the Vasa oak and joint information presented in this work can be used as input for a finite-element model of the Vasa ship for simulation of static and time-dependent behaviour on a larger scale. / Stötta Vasa

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