Because of property damage and people injuries in, almost, every year in different locations of the earth, unfortunately the topic of understanding trees and their risk assessments under wind forces has not lost its importance since approximately a half of the last century. In contrast to loss its importance, the number of researchers or studies increases with time thanks to inter-disciplinary studies on that topic. In this Thesis, tree dynamics and their risk assessments subjected to wind forces were addressed by two different disciplines (civil engineering and environmental conservation). To mention includes of this inter-disciplinary study, first, a finite element modeling was developed for a real tree in Belchertown, MA. Then this modeling was compared with the experimental tests. After comparing the model and the tests of the real tree, same methodology of the modeling was, again, applied to a different tree in Amherst, MA. Second, a number of wind samples were generated randomly in order to apply to the models of the trees. Then, by comparing the moments at the stem of the trees and calculated maximum moments of the stems, the fragility curves of the failures of these trees was obtained with respect to mean wind-speed of the random wind samples. Third, the decay effects on the fragility curves were investigated by considering decreasing moment capacity of tree cross-sections due to decays. Finally, crown structure effects on tree dynamics were examined by several parametric studies which were applied to the tree in Belchertown, MA. These parametric studies refer to separately changes in several physical (such as stem diameter, branch slenderness ratio etc.) and material property (MOE) of the tree. Thus, thanks to these parametric studies, tree dynamics were understood better and the complex relationship between the stem and branches of the tree was explained better. Those better understandings, off course, produced several important practical outcomes for the life of the trees and as well as human-being.

No description available.

<p>This thesis reports on shake table tests on fully-grouted reinforced masonry (RM) shear walls. The test walls covers a range of design parameters to facilitate benchmarking, a thorough performance investigation, and calibration of numerical models as well as development of fragility curves within the context of Performance Based Seismic Design (PBSD). The details of the experimental program undertaken, including general observations in terms of cracking patterns and failure modes of the tested walls and the results on the lateral strength, hysteretic response, dynamic properties, and the contribution of different displacement components to the response of the walls, are presented. More detailed analyses include seismic performance quantification of the walls in terms of inelastic behaviour characteristics, various energy components, and the effective dynamic properties of the tested walls. The analysis is concluded with development of simplified nonlinear response history analytical models and seismic fragility assessment tools for the tested walls. In general, the study results indicated that the displacement ductility capacity of the RM walls and their capability to dissipate energy through plastic hinging are higher than what is currently recognized by the National Building Code of Canada (NBCC). The fragility assessment study further indicated that similar walls are expected to conform to the current drift limits of the NBCC even at high seismic regions in Canada. The results of this study are expected to contribute to the growing Seismic Performance Database (SPD) of RM Seismic Force Resisting System (SFRS), and to the understanding of the lightly reinforced masonry wall system behaviour.</p> / Master of Applied Science (MASc)

The use of fully grouted reinforced masonry shear walls (RMSWs) has been growing in several areas around the world owing to their relative ease of construction and their in-plane ductile behavior. However, RMSWs possess low out-of-plane ductility which amplifies the vulnerability of such components under blast loading. Furthermore, the long time and high costs of recovery following devastating (deliberate or accidental) explosions have created a need for resilience-based design for risk mitigation, especially considering the different sources of associated uncertainty. As such, this study aims to lay out the foundations of a probabilistic resilience–based blast analysis and design framework. The framework should have the capability of quantifying the overall building post-blast functionality in order to estimate its recovery cost and time, and thus the building resilience following such a demand. The proposed framework will be specifically applied for RMSW buildings incurring blast loads through a profound investigation for the behavior of rectangular RMSWs as being a primary structural element in reinforced masonry buildings. The investigation will subsume an experimental and analytical evaluation for the performance of load-bearing RMSWs with different in-plane ductility levels subjected to out-of-plane quasi-static loading. This will be followed by a numerical investigation of RMSWs to conclude the blast probabilistic performance of RMSWs that can be applied within the proposed probabilistic resilience-based blast framework. The work in this dissertation presents a key step towards adopting resilience based analysis and design in future editions of blast-resistant construction standards and provides the decisionmakers with a complete insight into post-blast building functionality and its recovery. / Thesis / Doctor of Philosophy (PhD)

С момента появления смартфона стало ясно, что клиенты быстро перенимают даже очень сложную и дорогую технологию, если она облегчает им жизнь. Другими словами, пользователи ценят удобство и простоту. Эти основные ценности превратили автомобиль в определяющий технический культурный объект 20-го века. Теперь пришло время перевести эти свойства в контекст сегодняшних — и завтрашних — технологий и общества. Магистерская диссертация состоит из введения, трех глав, заключения, библиографического списка, включающего 150 наименований. Работа включает и 50 рисунков. Общий объем магистерской диссертации составляет 81 страницу. / Since the introduction of the smartphone, it has become clear that customers are quick to adopt even highly complex and expensive technology if it makes their lives easier. In other words, users value convenience and ease. These core values turned the automobile into the defining technical cultural item of the 20th century. Now it is time to translate these properties into the context of today's – and tomorrow's – technology and society. Master's thesis) consists of an introduction, three chapters, a conclusion, a bibliographic list, including 150 titles. The work includes and 50 figures. The total volume of the Master's thesis is 81 pages.

Quantitative and qualitative assessment of the seismic risk to highway bridges is crucial in pre-earthquake planning, and post-earthquake response of transportation systems. Such assessments provide valuable knowledge about a number of principal effects of earthquakes such as traffic disruption of the overall highway system, impact on the regions' economy and post-earthquake response and recovery, and more recently serve as measures to quantify resilience. Unlike previous work, this study captures unique bridge design attributes specific to California bridge classes along with their evolution over three significant design eras, separated by the historic 1971 San Fernando and 1989 Loma Prieta earthquakes (these events affected changes in bridge seismic design philosophy). This research developed next-generation fragility curves for four multispan concrete bridge classes by synthesizing new knowledge and emerging modeling capabilities, and by closely coordinating new and ongoing national research initiatives with expertise from bridge designers. A multi-phase framework was developed for generating fragility curves, which provides decision makers with essential tools for emergency response, design, planning, policy support, and maximizing investments in bridge retrofit. This framework encompasses generational changes in bridge design and construction details. Parameterized high-fidelity three-dimensional nonlinear analytical models are developed for the portfolios of bridge classes within different design eras. These models incorporate a wide range of geometric and material uncertainties, and their responses are characterized under seismic loadings. Fragility curves were then developed considering the vulnerability of multiple components and thereby help to quantify the performance of highway bridge networks and to study the impact of seismic design principles on the performance within a bridge class. This not only leads to the development of fragility relations that are unique and better suited for bridges in California, but also leads to the creation of better bridge classes and sub-bins that have more consistent performance characteristics than those currently provided by the National Bridge Inventory. Another important feature of this research is associated with the development of damage state definitions and grouping of bridge components in a way that they have similar consequences in terms of repair and traffic implications following a seismic event. These definitions are in alignment with the California Department of Transportation's design and operational experience, thereby enabling better performance assessment, emergency response, and management in the aftermath of a seismic event. The fragility curves developed as a part of this research will be employed in ShakeCast, a web-based post-earthquake situational awareness application that automatically retrieves earthquake shaking data and generates potential damage assessment notifications for emergency managers and responders. / Errata added at request of advisor and approved by Graduate Office, March 15 2016.

Que signifie bien vieillir en Afrique pour les personnes âgées vulnérables? Quelle est notre responsabilité pour ces personnes fragiles quand la globalisation de l’économie mondiale, les flux migratoires vers les métropoles occidentales, le contrôle les matières premières par des puissances industrielles et la fermeture des frontières des nantis aux plus démunis tendent à mettre de côté la question de la vieillesse ? Quel type d’utopie aidera les Africains à promouvoir une vraie éthique de la compassion ?En effet, la question de la vieillesse en Afrique est avant tout une question existentielle et éthique, raison pour laquelle la solution ne passera pas par la pitié, la vénération, les soins médicaux, mais par la prise en compte de la justice. Celle-ci remet à l’ordre du jour la responsabilité, la sollicitude, la compassion et le problème du pacte intergénérationnel.En somme, à travers la vieillesse, il s’agit d’interroger les traditions africaines sur le vivre-ensemble surtout dans la fragilité.Mots clés : Afrique, autonomie, dignité, éthique, fragilité, justice, pacte générationnel, politique, représentations, responsabilité, sollicitude, vieillesse, vulnérabilité. / What is the meaning of aging for vulnerable aged persons? The aging question is very often put aside when economical globalization, migrations in western towns, control of raw material by industrial powers and the borders’ control by rich countries against poor immigrants are the key issues in discussions. What kind of utopia will help Africans to promote an ethic of compassion?The question of aging in Africa is mainly an ethical and existential one, that is why its solution will come neither from pity and medical caring of aged people nor from veneration but from the way the question of justice is addressed. Justice put forward the very notions of responsibility, solicitude, compassion and intergenerational pact.Definitely, through aging question, we question fragility and living-together in African traditions.

Les polyamides sont des thermoplastiques techniques qui présentent de bonnes propriétés mécaniques et barrières. Le comportement viscoélastique complet des polyamides est rarement décrit dans la littérature à cause de la présence d'une phase cristalline et à l'instabilité thermique de ces polymères.Dans une première partie, le comportement rhéologique de polyamides amorphes PA 6I avec différentes masses molaires a été étudié. L'augmentation de la masse molaire se traduit par l'apparition d'un plateau caoutchoutique et le décalage du temps de relaxation terminal vers les plus basses fréquences, en accord avec les modèles de Rouse et de reptation. Des interactions ioniques ont été ajoutées au PA 6I en copolymérisant les mêmes monomères avec différents acides isophtaliques substitués, avec des taux de groupements ioniques de 5 à 20 mol%, ce qui entraîne une augmentation de la température de transition vitreuse de 10 à 40°C. Les courbes maîtresses des PA 6I et des copolyamides substitués non enchevêtrés se superposent dans toute la gamme de fréquences en utilisant une température de référence appropriée, proche mais non strictement identique à Tg. Les groupements ioniques ont un effet sur la fragilité dynamique, c'est-à-dire sur la variation en température de la réponse rhéologique près de Tg. Le modèle de Rouse décrit correctement la réponse rhéologique des polyamides non enchevêtrés, montrant que les interactions ioniques n'ont pas d'effet sur la viscoélasticité de ces matériaux. Les polyamides enchevêtrés suivent le modèle de la reptation. La masse entre enchevêtrements augmente avec l'ajout de groupements ioniques dû à une augmentation de la rigidité de la chaîne. La diffusion des rayons-X aux petits angles montre qu'il n'y a pas de ségrégation de domaines ioniques dans les copolyamides non enchevêtrés et une faible ségrégation dans les copolyamides enchevêtrés. L'ajout de liaisons hydrogènes plus fortes se traduit par l'augmentation de la masse entre enchevêtrements et de la Tg sans aucune modification significative dans l'allure des courbes maîtresses qui restent bien décrites par le modèle de Rouse. L'effet des groupements ioniques sur la dynamique à l'état solide (au-dessous de Tg) a été étudié par spectroscopie diélectrique. Les groupements ioniques n'ont pas d'effet sur les relaxations secondaires des polyamides, tandis que la relaxation alpha est décalée comme la Tg mesurée par DSC. Aucune différence n'a été observée entre les copolyamides ioniques et le PA 6I lors de tests de vieillissement physique, démontrant que les groupements ioniques n'introduisent pas d'hétérogénéités dynamiques / Polyamides are engineering thermoplastics which exhibit good mechanical and barrier properties. However, the viscoelastic behavior over the complete range of polyamide relaxation is a topic rarely mentioned in the literature due to the presence of a crystalline phase and lack of thermal stability.The rheological behavior of amorphous PA 6I with increasing molecular weight was studied. As molecular weight increases, a clear rubbery plateau appears and the longest relaxation time is shifted to lower frequencies, as expected by the Rouse and reptation models.Interactions were added to the PA by copolymerizing PA 6I’s monomers with different substituted isophthalic acids. Ionic copolyamides were synthesized in molar fractions from 5 to 20 mol%, inciting an increase of about 10 to 40°C in the glass transition temperature. Master curves of unentangled PA 6I and substituted polyamides, with similar molecular weight, overlap in the complete frequency range using an appropriate reference temperature, which is close to, but not identical to Tg. Ionic groups have an effect on the Angell’s dynamical fragility, i.e. on the temperature variation of the rheological response close to Tg. Dynamic moduli of unentangled polyamides were fitted with Rouse model, showing no effect of hydrogen bonds or ionic groups on the shape of the rheological master curves. The molecular weight between entanglements increases for ionic copolyamides due to an increase of chain rigidity. Small-angle X-ray scattering shows that no segregation of ionic domains occurs in unentangled ionic copolyamides, while entangled copolyamides show only weak segregation.Stronger hydrogen bonding resulted in a decrease of the molecular weight between entanglements. Nevertheless no significant difference was observed in the shape of master curves, which were fitted using the Rouse model.The effect of interacting groups on the local dynamics in the solid state (below Tg) was studied by dielectric spectroscopy. Ionic groups have no effect on secondary relaxations, while alpha-relaxation is shifted accordingly to Tg. No difference was observed between ionic copolyamides and PA 6I during aging experiments, as ionic groups do not act as dynamic heterogeneities, i.e., zones where the local dynamics are heterogeneous due to different local ionic fractions

Atualmente existem diferentes definições para o conceito de fragilidade ambiental, o que dificulta sua aplicação e a comparação entre os resultados de diferentes métodos. Este trabalho realiza uma revisão bibliográfica sistemática a cerca desse conceito e adota a definição considerada mais adequada. Com base na definição adotada foi proposto e aplicado um método para avaliar a fragilidade ambiental de uma área de estudo. Esse método utiliza pesos para ponderar os diferentes atributos (meio físico, biótico e socioeconômico) envolvidos na análise de fragilidade ambiental, que são definidos com a aplicação do Processo de Análise Hierárquica (AHP). O método proposto também se fundamenta na utilização de um programa de Sistema de Informação Geográfica (SIG) para a estruturação da base de dados, a realização das análises espaciais e a ponderação dos mapas necessários. A área de estudo corresponde a um setor do oleoduto São Paulo &#8211; Brasília (OSBRA), com extensão de 18,5 km e largura de 2 km (área total de 83,99 km²) e utilizou-se uma base cartográfica digital na escala 1:10.000. Foram realizadas vistorias de campo para levantar pontos de observação de superfície e para coletar amostras de solo. Realizaram-se ensaios geotécnicos, químicos e mineralógicos com as amostras coletadas. A aplicação do método consistiu na geração de mapas de suscetibilidade intermediários, que combinados geraram o mapa de fragilidade ambiental. Foi importante a utilização do método AHP, pois ele reduz a subjetividade das ponderações qualitativas realizadas. Os resultados obtidos esclarecem a definição do conceito de fragilidade ambiental, além de mostrar a importância da seleção e ponderação dos atributos utilizados no método. O mapa final gerado também permitiu avaliar a sensibilidade do método e seu potencial de aplicação prática. / Currently there are different definitions to the concept of environmental fragility; it complicates its application and makes difficult to compare between different methods. This work addresses the main definitions to this concept and adopts the one considered the most proper. Based in the adopted definition it was proposed a method to evaluate the environmental fragility of a study area. This method applies weights to the different attributes (physical, biotic and socioeconomic) related to the environmental fragility analysis, which are assigned using the Analytic Hierarchy Process (AHP). The method also uses Geographic Information System (GIS) software to structure the database, to conduct the spatial analysis and to assign weights to the maps. The study area is a sector of the São Paulo &#8211; Brasília oil pipeline (OSBRA), covering 18.5 km length and 2 km wide (total area of 83,99 km²) and it was used a digital cartographic map at the scale of 1:10,000. Field trips were made to obtain surface observation points and to collect soil samples. Geological and geotechnical tests, mineralogical tests and chemistry analysis were conducted with the soil samples. The method application consists in generating intermediates susceptibility maps, that were combined to generate the environmental fragility map. It was important to use the AHP method, because it reduces the subjectivity of the qualitative weight assignment. The obtained results elucidate the environmental fragility concept and show the importance of the selection and weight assignment of the attributes used in the method. Moreover, the final map provided to evaluate the method sensitivity and its potential of practical application.

Este trabalho visa aplicar e comparar duas metodologias de análise ambiental, a de Ross (1994) e a de Crepani et al. (2001), que abordam o ambiente dentro de uma perspectiva sistêmica, utilizando o conceito de Unidades Ecodinâmicas proposto por Tricart (1977). O objeto do presente trabalho é o Trecho Leste do Rodoanel Metropolitano de São Paulo, parte do anel viário concebido como uma alternativa ao tráfego de passagem pelo centro da Região Metropolitana de São Paulo, o qual o DERSA estabeleceu o traçado definitivo que será implantado a partir de setembro de 2011. Na geração dos documentos cartográficos analíticos e de síntese foram aplicadas técnicas de Geoprocessamento. Também foram utilizadas imagens de Sensoriamento Remoto para a extração de informações referentes à cobertura vegetal e uso do solo. Os mapeamentos de síntese e os traçados gerados automaticamente apresentaram resultados bem divergentes em razão do tratamento desigual das metodologias. Enquanto a proposta de Ross (1994) enfatiza a questão geomorfológica, basicamente as declividades, a metodologia de Crepani et al. (2001) adota uma equivalência entre as variáveis e é mais abrangente ao analisar o ambiente, apresentando uma maior compatibilidade com a área de estudo. Contudo, as variáveis ambientais possuem uma importância relativa, os aspectos econômicos e políticos parecem ter sido mais relevantes na definição do traçado final do Trecho Leste do Rodoanel. / This work aims to apply and compare two methods of environmental analysis, the Ross (1994) and the Crepani et al. (2001), that address the environment within a systemic perspective, using the concept of ecodynamics units proposed by Tricart (1977). The object of this work is the Section East of the São Paulo Metropolitan Beltway, part of the ring road designed as an alternative to traffic passing through the center of the São Paulo metropolitan region, which DERSA set the final route will be implemented from September 2011. In the generation of analytical and synthesis cartographic Geoprocessing techniques were applied. Were also used Remote Sensing images to extract information on land cover and land use. Mappings synthesis and the traces generated automatically showed conflicting results because of unequal treatment of methodologies. While the proposed Ross (1994) emphasizes the issue geomorphological, basically the slopes, the methodology of Crepani et al. (2001) adopts an equivalence between the variables and is more comprehensive in analyzing the environment, providing greater compatibility with the study area. However, environmental variables have a relative importance, the economic and political aspects seem to have been more relevant in defining the final route of the Section East of the Beltway.