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Evaluation Of Seismic Resistance Of Traditional Ottoman Timber Frame HousesAktas, Yasemin Didem 01 August 2011 (has links) (PDF)
The aim of this study is to evaluate the seismic resistance of traditional Ottoman timber frame &ldquo / himis&rdquo / structures, which form the major part of Turkey&rsquo / s cultural heritage, from an engineering point of view. On the other hand, the seismic resistance of traditional Ottoman timber frame structures was not evaluated from an engineering perspective.
For the aim of seismic resistance evaluation of traditional Ottoman timber frame houses, the TUBITAK (the Scientific and Technological Research Council of Turkey) project numbered 106M499 was carried out. Within this framework, 16 tests were carried out in the Structural Mechanics Laboratory of Middle East Technical University, by means of 8 1-1 scale timber frames of different geometrical configurations and material, carefully selected from traditional houses in Safranbolu, representing Ottoman timber frame &ldquo / himis&rdquo / technique. The frames were tested without and with different infill/covering types, and parameters that directly or indirectly indicate the behavior of a structure under earthquake loading were derived from the results obtained at the end of experimental work. In addition, capacity calculations were carried out for each test, using ATC-40 procedure.
The results demonstrated that Ottoman timber frame &ldquo / himis&rdquo / houses are seismically resistant, and yet there are a number of important points that should be obeyed in their construction regarding size of diagonal elements, size and placement of openings, intervals between vertical studs, as well as connection details. It is also seen that certain infill/covering materials/methods are more advantageous than the others / for example, covering techniques results in a higher amount of maximum lateral load that the frame can bear under the same displacement. Infill with masonry blocks results in a larger increase in weight than in load bearing capacity. The conclusions drawn are intended to be used not only in the conservation of such structures but they are also expected to direct modern seismically resistant constructions.
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Effects Of Frame Aspect Ratio On The Seismic Performance Improvement Of Panel Strengthening TechniqueOkuyucu, Dilek 01 August 2011 (has links) (PDF)
PC panel strengthening technique was developed in M.E.T.U. Structural Mechanics
Laboratory in order to respond the need of practical and efficient pre-quake seismic
strengthening procedures applicable to RC framed structures. The idea behind the
method is simply to convert the non-structural infills into load bearing structural
elements by gluing PC panels over the existing infill wall surface. The remarkable
advantages of the procedure is not only the considerable amount of seismic
performance improvement but also the simplicity of application, very low levels of
disturbance to the occupants and most importantly, the applicability during service.
A number of PC panel application parameters were experimentally investigated by
previous researchers. The success of PC panel method on seismic performance
improvement of RC frames with different aspect ratios was experimentally investigated
in the present study. Total of fifteen, 1:3 scaled, one-bay, two-storey RC frames were
tested in three various aspect ratio series. Constant axial load was applied to the
columns and reversed cyclic load was applied in the lateral direction. Hollow brick
v
infilled frame and cast-in-place RC infilled frame were the lower and upper bound
reference specimens, respectively.
Seismic performance indicators such as response envelope curves, lateral load carrying
capacities, cumulative energy dissipations, initial stiffness indicators and ductility
values clearly showed the effectiveness of PC panel application over different geometry
of RC frames of concern. Moreover, PC panel application either with rectangular or
with strip shaped PC panels provided seismic performance improvement to be almost
equal to that of cast-in-place RC infill application for all series.
Equivalent diagonal strut concept was followed in analytical studies to simulate the
infills of RC frame openings. The required strut material properties were estimated
from total of eighteen individual wall panel tests. The bond-slip effect, due to
utilization low strength of concrete and plain rebars, was also investigated and
introduced to the analytical frame models. Non-linear push over analysis was
performed for all specimens in OpenSees computer software. The analytical results
were compared with that of experimental response envelopes.
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A case study of brownfield redevelopment in Wellston, MOWilliams, Ashley January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture/Regional and Community Planning / John W. Keller / This report reviews pertinent knowledge regarding brownfield redevelopment, specifically the processes and issues involved. It addresses such topics as the type of brownfield sites, steps to remediation, types of remediation and barriers to redevelopment. Finally, a precedent study of Wellston, MO is presented. This study examines the impact that the development of two abandoned brownfield sites, Wellston Electrical Company and ABEX Foundry, had on the entire community. It was found that the onset of the development of these sites spurred the revitalization of the whole city of Wellston, having a positive influence across the city and surrounding area.
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Seismic performance, analysis, and design of hybrid concrete-masonryRedmond, Laura M. 08 June 2015 (has links)
Caribbean-style hybrid concrete-masonry structures consist of a reinforced concrete frame with partially grouted and reinforced infill masonry walls. The infill walls are typically connected to the RC frame with cast-in-place dowel reinforcement along one or more edges of the wall. There is limited guidance in masonry codes to design these types of structures, and their seismic performance has not been characterized with experimental tests. In this work, an experimental program characterized the seismic behavior of hybrid concrete-masonry frames and showed they do not exhibit the typical strut mechanism observed in unreinforced masonry infill structures. In addition, a detailed finite element modeling scheme and calibration methodology was developed for modeling partially grouted masonry. This model includes a novel calibration method to account for the difference in the shear and tensile behavior of bed joints with grouted and ungrouted cells, and a method to account for the contribution of vertical reinforcement to the shear capacity of the bed joints with grouted cells. Finally, simplified models were proposed for use in engineering design. A modification of the TMS 402 strut model for hybrid concrete-masonry was suggested to incorporate the effects of the masonry infill and connections in large models.
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Assessing neighborhoods, districts, and corridors : a method for applying selected new urbanist principles to infill situationsMcCarley, William J. January 2001 (has links)
This research proposes to determine the ten major social and psychological needs of a neighborhood scale community, and develop an assessment model that will provide designers and developers with insight into which New Urbanist principles should be applied, and to what extent application should occur, to better address the community's social and psychological needs.Failure of designers to consider adequately the psychological and social needs of groups of individuals has brought about consequences detrimental to the long-term livelihood of communities. The inability of a community to meet the needs of its inhabitants creates a state of discontent and "disconnect" among residents, thereby encouraging residents to leave their current community and relocate (sprawl) elsewhere in order to try and attain satisfaction. Attempts at addressing the discontent often focus on improving "quality of life" through the inclusion of open space, pedestrian-oriented streets, and other amenities. Often times, these physical design solutions gloss over, or ignore entirely, the community's psychological and social needs.Social and psychological factors are integral to a community's well being. According to the concepts of holism and wellness, "health" is gauged by how well individuals measure up in all dimensions of needs: physical, emotional, social, occupational, intellectual, and spiritual. (Robbins, Powers, and Burgess 1991) From the reverse perspective, individuals who have deficiencies in one or more dimensions can be considered "unhealthy." The wellness concept carries over from the individual to our built environments: communities that fail to inclusively meet the needs of their residents can be considered "unhealthy," or incomplete, from a wellness perspective.To remedy the incompleteness, designers and developers must focus on quality infill development that addresses deficiencies in a community, thereby bringing the community closer to a wellness balance. Effective evaluation and appropriate application of proposed infill developments are critical to the suitability of the solutions. In short, only by carefully considering the problems in our communities will designers and developers generate appropriate solutions that set our existing communities along the path to health, and solve the linked problems of disconnect, placelessness, and sprawl. / Department of Landscape Architecture
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Architecture, geodynamic evolution and sedimentary filling of the levant basin : a 3D quantitative approach based on seismic data / Architecture, évolution géodynamique et remplissage sédimentaire du bassin levant : une approche quantitative 3D basée sur données sismiques.Hawie, Nicolas 03 February 2014 (has links)
Les études sédimentologiques et biostratigraphiques menées au Liban couplés avec données sismiques 2D de réflexion en mer ont permis de proposer un nouveau cadre tectono-stratigraphique pour la région Levantine a partir du Mésozoïque. L'interprétation sismique soutenue par une analyse détaillée des faciès à permis de représenter les environnements de dépôt au large du Liban où aucun puits n'a été foré. Le rifting dans le bassin du Levant prend fin au Jurassique moyen. L'initiation de subduction de la plaque Afro-Arabe sous l'Eurasie au Crétacé supérieur est suivie par des mouvements décrochants à partir du Miocène. L'interaction entre ces événements géodynamiques ainsi que les fluctuations du niveau marin affecte le remplissage sédimentaire du bassin. Au cours du Jurassique et du Crétacé, la marge Levantine est dominée par l'évolution de plate-forme carbonatée tandis qu'un système mixte (silicoclastic et carbonaté) en eau profonde ont prévalu dans le bassin au cours de l'Oligo-Miocène. Trois grandes voies sédimentaires sont attendus à conduire d'importantes quantités de matériel clastiques dans le bassin: (1) les canyons incisant la marge, (2) la région de Lattaquié (Syrie) et (3) le fan profond du Nil. L'analyse régionale des systèmes de drainage a été réalisée pour estimer la contribution au remplissage du bassin des différentes sources de sédiments. Un modèle stratigraphique, Dionisos, a été utilisé pour tester les scénarios du remplissage du bassin pendant le Miocène Moyen et Supérieur. Une comparaison avec les systèmes de drainage actuels a permis une meilleure évaluation de la plausibilité des volumes sédimentaires attendus pour chaque source. / Sedimentological and biostratigraphic investigations onshore Lebanon coupled with 2D offshore reflection seismic data allowed proposing a new Mesozoic-Present tectono-stratigraphic framework for the northern Levant Margin and Basin. The seismic interpretation supported by in-depth facies analysis permitted to depict the potential depositional environments offshore Lebanon as no well has yet been drilled. The Levant region has been affected by successive geodynamic events that modified the architecture of its margin and basin from a Late Triassic to Middle Jurassic rift into a Late Cretaceous subduction followed by collision and Miocene-Present strike slip motion. The interplay between major geodynamic events as well as sea level fluctuations impacted on the sedimentary infill of the basin. During Jurassic and Cretaceous, the Levant Margin is dominated by the aggradation of a carbonate platform while deepwater mixed-systems prevailed in the basin during the Oligo-Miocene, three major sedimentary pathways are expected to drive important quantities of clastic material into the Levant Basin: (1) canyons along the Levant Margin, (2) the Latakia region (coastlal Syria) and (3) the Nile Deep sea cone. Regional drainage system analysis was performed to estimate the contribution of the different sediment sources to the infill of the basin. A numerical stratigraphic forward model, Dionisos, was used to test the Middle-Late Miocene source-to-sink scenarios permitting to better assess the plausibility of the expected sedimentary volumes for each source through a comparison with actual drainage systems
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Reconciling Oregon's Smart Growth Goals with Local Policy Choice: An Empirical Study of Growth Management, Urban Form, and Development Outcomes in Eugene, Keizer, Salem, and SpringfieldWitzig, Monica 17 June 2014 (has links)
Oregon's Statewide Planning Goals embody Smart Growth in their effort to revitalize urban areas, finance environmentally responsible transportation systems, provide housing options, and protect natural resources; yet the State defers to its municipalities to implement this planning framework. This research focuses on Goal 14 (Urbanization), linking most directly to Smart Growth Principle 7 (Strengthen and Direct Development toward Existing Communities). It assesses Eugene's, Keizer's, Salem's, and Springfield's growth management policies that specifically target infill development of single family homes against this Goal and Principle. Though these municipalities must demonstrate consistency with the same Goals (see Supplemental File 1 for this context), this research questions whether sufficiently different policy approaches to curtailing sprawl yield significantly different results. The primary analytical method is a logistic regression that uses parcel-level data to understand how administration affects development by isolating these policies' direct effects on observed outcomes (see Supplemental File 2 for this theory).
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Pórticos em concreto pré-moldado preenchidos com alvenaria participante / Infill walls in precast concrete framesMedeiros, Wallison January 2018 (has links)
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Previous issue date: 2018 / This research presents a study on the behavior of precast concrete frames with participating masonry infill to be considered in the design of a building lateral load bracing system. The study brings a literature review on the topic. An experimental testing of a reinforced concrete frame infilled or not with masonry is used to calibrate a finite element model using the Simulia Abaqus 2017 package. The model uses concrete damage plasticity to consider both the concrete and the masonry behaviour. Embedded elements are used to consider rebars inside the concrete. Masonry elements are considered homogeneous with contact surfaces along the concrete-masonry interface. After the properties were calibrated the numerical models showed excellent accuracy when compared to the experimental tests. Precast concrete frames, whose dimensions and properties were from a real case, was then modelled with and without the participating masonry frame. The column-corbel and beam connection was modelled with solid elements with contact surface on the interface allowing to close represent its behaviour. Models considered a frame with one, five and ten storeys, two masonry strength and the use or nor of a mortar layer to fix masonry under the concrete beam. Conclusion from the finite element model analyses indicate the influence of each parameter on the system behaviour. The FEM results were then used to calibrate the width of a diagonal truss to be used in simple bar element models. Finally, a 3D-frame model was used to evaluate a actual 10-story precast concrete building considering or not the participating infill masonry. Only two masonry walls, close to the building central core and without openings, were considered yet results indicate great influence on considering the participating infill leading to an efficient building design. Future work is proposed to experimentally evaluate the conclusions from the numerical analyses here reported. / O presente trabalho realizou um estudo sobre o comportamento de estruturas aporticadas em concreto pré-moldado preenchidas com painéis de alvenaria, para fim de contraventamento de edificações, considerando a contribuição dessa alvenaria de preenchimento no pórtico pré-moldado para análise de ações horizontais. O estudo traz uma revisão da literatura sobre o tema. Um ensaio experimental de um pórtico de concreto armado preenchido ou não com alvenaria é usado para calibrar um modelo de elementos finitos usando o pacote Simulia Abaqus 2017. O modelo utiliza o dano plástico do concreto (CDP) para considerar o comportamento do concreto e alvenaria. Elementos embutidos são usados para considerar armaduras dentro do concreto. Os elementos de alvenaria são considerados homogêneos com as superfícies de contato ao longo da interface concreto-alvenaria. Depois que as propriedades foram calibradas, os modelos numéricos apresentaram excelente precisão quando comparados aos testes experimentais. Os quadros de concreto pré-fabricados, cujas dimensões e propriedades eram de um caso real, foram então modelados com e sem o preenchimento de alvenaria participante. A conexão pilar-viga foi modelada com elementos sólidos com superfície de contato na interface permitindo representar seu comportamento. Os modelos considerados foram um quadro com um, cinco e dez andares, duas resistências de alvenaria e o uso ou não de uma camada de argamassa para fixar alvenaria sob a viga de concreto. A conclusão das análises do modelo de elementos finitos indica a influência de cada parâmetro no comportamento do sistema. Os resultados de MEF foram utilizados para calibrar a largura de uma diagonal equivalente para ser usado em modelos simples de elementos de barras. Finalmente, um modelo de pórticos em 3D foi usado para avaliar um prédio de concreto pré-moldado de 10 andares, considerando ou não a alvenaria participante. Apenas duas paredes de alvenaria, perto do núcleo central do edifício e sem aberturas foram consideradas, os resultados indicam grande influência ao considerar o preenchimento participante, levando a um projeto de construção eficiente. O trabalho futuro é proposto para avaliar experimentalmente as conclusões das análises numéricas aqui relatadas.
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Welding of light gauge infill panels for steel plate shear wallsNeilson, David Andrew Hunter 11 1900 (has links)
Ductile steel plate shear walls are an established lateral load resisting system. Past research indicates that cold-rolled infill panels less than 1 mm in thickness present one solution to an overstrength problem arising from selecting an infill panel thickness based on ease of welding and handling. This research program examines several possible welding procedures and joint geometry to connect the thin infill panel to the thick boundary elements.
Primary welding parameters include short-circuiting gas metal arc welding process, electrode and shielding gas selection, heat input, and use of a chill strip. Four configurations of the infill panel-to-boundary element joint and two configurations of a lap splice joint between two sheets of thin steel in the infill panel were tested in monotonic tension and cyclic tension-compression. A quasi-static cyclic test of a single-storey moment resisting frame steel plate shear wall validated the use of one welding procedure and joint geometry. / Structural Engineering
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Planning for greyfield redevelopment in Edmonton, AB: impeding and facilitating factorsOnishenko, David January 2012 (has links)
Spurred by changing retail and development patterns, as well as continuous suburban growth, greyfield sites can be found at the heart of most postwar suburbs in North American municipalities. Ranging in definition, greyfields are best described as an “underused, economically obsolete, retail tract located in an inner ring suburb that requires significant public and private involvement to curtail decline” (Feronti, 2003, p.11).
However, tied to demographic trends and increased municipal urbanization, these vacated retail sites are positioned well for redevelopment. Yet, the redevelopment process of these sites is fraught with impeding and facilitating factors that can have significant implications for redevelopment options and viability. As such, research questions considered were: Do municipalities address greyfield challenges and opportunities? What factors impede and facilitate greyfield redevelopment? This thesis also asks these questions within the context of the City of Edmonton’s current policy and existing built form, and asked: How should greyfields be planned in the City of Edmonton?
This thesis attempts to answer these questions through a review and analysis of existing literature, case studies (Belmar in Lakewood, Colorado and Century Park in Edmonton, Alberta) and through primary research conducted with key stakeholders. The research found that municipalities were largely unacquainted with the challenges and opportunities of greyfield redevelopment. Where support guidelines did exist, they were largely aspirational and lacked consideration for the unique impeding and facilitating factors of greyfield redevelopment. It was found that impeding factors to greyfield redevelopment ranged from administrative hurdles fraught with inexperience in greyfield redevelopment, to financial and land economic constraints. Facilitating factors were found in collaborative stakeholder consultation, municipal and administrative leadership, and a range of supportive fiscal mechanisms. Lastly, ten recommendations to facilitate greyfield redevelop within the City of Edmonton were discussed.
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