This project explores the issue of revealing the structural integrity of a building through the design of a recreational sports facility. The designated site for this sports facility is the River's Edge Sports Complex located in Roanoke, Virginia. A unique setting because the Roanoke River nearly cuts through the center of this site dividing the northern half with the existing football stadium, Victory Stadium, the National Guard Reserve Armory, and Maher Baseball Field from the southern portion containing athletic fields, tennis courts, and a playground. In order to consolidate the facilities into one sports complex, I propose a number of interventions including a bridge building, observation tower, coliseum, natatorium, racquetball courts, and exercise rooms. The goal of providing a smooth unifying path over the river, while creating a unique setting, presents an intriguing architectural challenge. The investigation focuses on the appropriate architectural expressions and structural possibilities of the long spanning bridge building since it is the central unifying element of the sports complex. / Master of Architecture

This research is aimed at investigating and analyzing the rain-windinduced cable vibration phenomena experienced in cables of cable-stayed bridges and also the countermeasures employed by engineers to mitigate the large-amplitude vibration problem reported by various researchers around the world. In order to investigate the problem of the water rivulet creation at the top of the cable surface, a single-degree-of-freedom (SDOF) analytical model was developed and analyzed. This thesis studies the aerodynamic instability of cables in cable-stayed bridges by doing literature review of a typical in-situ test, developing a single degree-of-freedom (SDOF) analytical model, and an ANSYS finite element model. Furthermore, a linear viscous damper that acts as a countermeasure to the large amplitudes of vibration is reported and analyzed. The suppression characteristics and damper effectiveness of such countermeasure are summarized. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Esse trabalho consiste na determinação das velocidades críticas do vento e das amplitudes das vibrações numa estrutura composta por uma viga engastada suspensa por um estai (cabo), submetida aos efeitos de vento e chuva. Foi considerada a deformação no cabo devido ao carregamento do peso próprio e o acoplamento não-linear das vibrações do cabo e da viga. Três modos de vibração são de especial interesse, chamados de primeiro modo global (flexão da viga e vibração no cabo), primeiro modo local (vibração no cabo, com flexão na viga desprezável) e primeiro modo à torção. O modelo foi reduzido a três graus de liberdade. A modelagem dos carregamentos aerodinâmicos aplicados na viga foi feita segundo procedimentos tradicionais. O carregamento aerodinâmico aplicado ao cabo sob efeito de chuva e vento também foi levado em consideração. Para a redução do modelo matemático, os coeficientes de rigidez e de amortecimento equivalente são definidos e dependem parametricamente da velocidade do vento. Os termos não-lineares são devidos ao acoplamento das vibrações do cabo e da viga à flexão (no plano do cabo) e também aos efeitos aeroelásticos no cabo. Os seguintes regimes instáveis são avaliados: o efeito de galope (galloping) no cabo, o drapejamento (flutter) unimodal na torção e o drapejamento (flutter) do modo de flexão da viga em conjunto com vibrações transversais do cabo. / This paper is concerned with determining wind critical velocities and post-critical vibration amplitudes in a cable-stayed beam, under wind-rain condition. It is considered the cable sag due to the dead load plus the non-linear coupling between the vibration of both the cable and the beam. Three modes are of special interest, namely the first global mode (beam bending & cable vibration), the first local mode (cable vibration & negligible beam bending) and the first torsion mode. A reduced mathematical model, with three degrees of freedom, is also developed. With regard to the modelling of the aerodynamic loads applied to the beam, it can be performed after extension of classical guidelines. The aerodynamic loads applied to the cable under rain are also taken into account. For the reduced mathematical model, equivalent damping and stiffness coefficients will be defined, which depend parametrically on the wind velocity. Non-linear terms appear due to the coupling between the cable and the beam bending vibrations, and also to the aero-elastic non-linear effects on the cable. Different unstable regimes are surveyed such as the cable galloping, the unimodal flutter in torsion and the unimodal flutter with beam bending and cable vibrations coupled.

[Truncated abstract] As a consequence of the increase in terrorist incidents, many comprehensive researches, both experimental and numerical modelling of structure and blast interaction, have been conducted to examine the behaviour of civilian structures under dynamic explosion and its impact. Nevertheless most of the works in literature are limited to response of simple structures such as masonry walls, reinforced concrete beams, columns and slabs. Although these studies can provide researchers and structural engineers a good fundamental knowledge regarding blast load effect, it is more likely for blast load to act upon entire structures in actual explosion events. The interaction between blast load and structures, as well as the interaction among structural members may well affect the structural response and damage. Therefore it is necessary to analyse more realistic reinforced concrete structures in order to gain an extensive knowledge on the possible structural response under blast load effect. Among all the civilian structures, bridges are considered to be the most vulnerable to terrorist threat and hence detailed investigation in the dynamic response of these structures is essential. This thesis focuses on the study of the response of a modern cable-stayed bridge under blast loadings. ... Firstly, analysis is conducted to examine the failure of four main components namely pier, tower, concrete back span and steel composite main span under close proximity dynamic impact of a 1000 kg TNT equivalent blast load. Secondly, based on such results, the remainder of the bridge structure is then tested by utilizing the loading condition specified in the US Department of Defence (DoD) guideline with the aim to investigate the possibility of bridge collapse after the damage of these components. It is found that failure of the vertical load bearing elements (i.e. pier and tower) will lead to catastrophic collapse of the bridge. Assuming that terrorist threat cannot be avoided, hence protective measures must be implemented into the bridge structure to reduce the damage induced by explosive blast impact and to prevent bridge from collapse. As such, a safe standoff distance is determined for both the pier and tower under the blast impact of 10000 kg TNT equivalent. This information would allow the bridge designer to identify the critical location for placing blast barriers for protection purpose. For the case of bridge deck explosion, carbon fibre reinforced polymer (CFRP) is employed to examine in respect of its effectiveness in strengthening the concrete structure against blast load. In this research, appropriate contact is employed for the numerical model to account for the epoxy resin layer between the CFRP and concrete. In addition, to ensure that the CFRP can perform to its full capacity, anchors are also considered in the numerical study to minimize the chance of debonding due to the weakening of the epoxy. The results reveal that although severe damage can still be seen for locations in close proximity to the explosive charge, the use of CFRP did reduce the dynamic response of the bridge deck as compared to the unprotected case scenario. Further investigation is also carried out to examine the change in damaged zone and global response through variation in CFRP thickness.

Cable-stayed bridges are popular these days in spite of their complexity in shape and design. Cable-stayed bridges are ideal for a navigational channel due to their high clearance and long central span. These types of bridges also possess advantages over suspension bridges, especially when local site conditions are not suitable for anchoring the towers. In most of the cases, cable-stayed bridges are self-supportive or require less anchorage. Although symmetrical cable-stayed bridges are dominant, asymmetrical bridges are also common as well due to ground layouts and other restrictions like economy, aesthetic purpose. Added counter weight and eccentricity of asymmetrical bridge may highly affect the response of the structure under earthquake loading. For the same length span bridge, the response of the asymmetric one may have an amplified response compared to the symmetric one with the same span length and also, may not follow any predictable trend. This study presents a multi-support analysis for four models, which are, 200 m symmetrical, 400 m symmetrical, 200 m asymmetrical and 400 m asymmetrical bridges. Ground motions has been recorded by using accelerometers. The recorded ground motion depends on the direction of the accelerometer. To remove this dependency, the principal components of each ground motion were found and used for the analysis and the models were excited in the transverse direction. The models were run under both multi-support excitation and identical-support excitation for displacement time-history analysis using SAP2000. Ratio of stresses and deflections were compared for the bridges with the same span length. According to this study, on 200 m asymmetrical bridge, multi-support excitation factored responses up to 4%, while on 400 m asymmetrical bridge, responses are factored up to 20% compared to the identical-support excitation. It is noted that responses of asymmetrical bridges are factored up making identical-support excitation non-conservative.

nÃo hà / Esta dissertaÃÃo, denominada Espectro da Ponte Estaiada e do Mirante em meio ao circuito do Turismo de NegÃcios & Eventos, objetiva compreender, no campo da avaliaÃÃo de polÃticas pÃblicas, a concepÃÃo da polÃtica de turismo para a cidade de Fortaleza atravÃs da construÃÃo de Ãcones urbanos, vinculados ao setor turÃstico, notadamente o segmento de NegÃcios & Eventos. Toma como objeto especÃfico de sua avaliaÃÃo, a proposta do Governo do Estado do Cearà em construir a Ponte Estaiada e o Mirante como Ãcones urbanos para atrair novos fluxos do capital financeiro e investimentos no setor turÃstico. A despeito da nÃo materialidade das obras, seus espectros mantÃm a atualidade polÃtica, uma vez que foram constituÃdos dentro de novas configuraÃÃes de turismo de NegÃcios & Eventos em consonÃncia com as linhas prevalecentes das polÃticas pÃblicas de turismo no Estado do Cearà das Ãltimas dÃcadas. O eixo central da anÃlise realiza a crÃtica da lÃgica intrÃnseca à concepÃÃo de desenvolvimento da cidade, a partir dos investimentos na Ãrea do turismo na construÃÃo de novos equipamentos, marcada ainda pela forte intervenÃÃo do Estado junto à esfera privada, remodelando o espaÃo da cidade sob a Ãgide da acumulaÃÃo do capital. Inspirada no modelo de âAvaliaÃÃo em Profundidadeâ, desenvolvida por Rodrigues (2008), que em seu construto estabelece procedimentos sistemÃticos de investigaÃÃo, baseados em eixos de anÃlise que orientam as prÃticas investigativas na Ãrea, empreendi esforÃos avaliativos a partir dos trÃs primeiros eixos analÃticos configurados pela autora (anÃlise de conteÃdo do programa, contexto da formulaÃÃo da polÃtica e trajetÃria institucional). Avaliei documentos oficiais e fiz uso de entrevistas nÃo estruturadas, sendo esta a principal tÃcnica investigativa, se configurando em uma pesquisa predominantemente qualitativa. Em decorrÃncia dessa opÃÃo, meu plano investigativo transcendeu a anÃlise de dados quantitativos coletados em formatos padronizados ou em abordagens lineares. Como resultado dessa avaliaÃÃo, pude compreender a metrÃpole como um lugar onde as transformaÃÃes urbanas e a produÃÃo do espaÃo sÃo realizadas em funÃÃo da reproduÃÃo do capital e a total preponderÃncia dessas obras e projetos urbanos diante da falta de instrumentos eficazes de controle social em torno do conjunto de aÃÃes segregacionistas de cunho espacial, que visam à obtenÃÃo de lucro e o consequente privilÃgio dos setores imobiliÃrios dominantes. Averiguei que a polÃtica de turismo està ancorada em um modelo de desenvolvimento urbanÃstico mercantil, inserido no cenÃrio de investimentos de capitais pÃblicos e privados, nacionais e internacionais, o que revela a intercessÃo entre o segmento de NegÃcios & Eventos e o setor imobiliÃrio, gerando novas configuraÃÃes espaciais, uma vez que esta modalidade de turismo tem por base as obras ligadas aos grandes eventos e a investimentos em infraestrutura viÃria e de lazer. / This dissertation, titled Specter of the Cable-stayed Bridge and the Observation Tower amid the Circuit of Business Tourism and Events, aims at understanding, with evaluation of public policies, a conception of touristic entrepreneurship for the city of Fortaleza through construction of urban icons, linked to the sectors that deal with it, notably the Business and Events Segment. The specific goal of this evaluation is the proposal by the Government of the State of Cearà to build the Cable-stayed Bridge and the Observation Tower as an urban icon to attract new flows of financial capital and investments directed to the sector of tourism. In spite of the non-materiality of the works, their specters support political relevance, since they were constituted within new configurations of Business Tourism & Events and agree with the prevailing lines of public policies of tourism in the State of Cearà of the last decades. The main effort of the analysis is to present a critique of the intrinsic logic applied to the conception of development of the city, starting from investments in tourism for construction of new equipment, still marked by strong State intervention that privileges the private sector, by remodeling city environs under the aegis of capital accumulation. Inspired by the "In Depth Assessment Modelâ developed by Rodrigues (2008), which in its construct establishes systematic rules of investigation, based on axes of analysis that guide investigative practices in the area, this dissertation reveals evaluation efforts attached to the first three analytical axes as designed by the author (content analysis of the program, context of policy formulation and institutional trajectory). This work resorted to official documents and unstructured interviews, the latter being the main investigative technique, and leading to predominantly a qualitative research. As an upshot of this option, the research plan transcended the analysis of quantitative data collected in standardized formats or in linear approaches. As a result of this evaluation, one tends to understand the metropolis as a place where urban transformations and opening of spaces march with capital reproduction and total preponderance of urban works and projects in the face of the lack of effective instruments of social controls around the set of spatial segregationist actions for obtaining profit and the consequent privilege of dominant real estate sectors. It was noticed that tourism-related policies anchor in a model of commercial urban development, inserted in the scenario of investments of public and private, national and international capital, which reveals intercession of the Business & Events Segment and the real estate sector, generating new spatial configurations, since this modality of tourism focus on works linked to major events and investments in road and leisure infrastructure.

Esse trabalho consiste na determinação das velocidades críticas do vento e das amplitudes das vibrações numa estrutura composta por uma viga engastada suspensa por um estai (cabo), submetida aos efeitos de vento e chuva. Foi considerada a deformação no cabo devido ao carregamento do peso próprio e o acoplamento não-linear das vibrações do cabo e da viga. Três modos de vibração são de especial interesse, chamados de primeiro modo global (flexão da viga e vibração no cabo), primeiro modo local (vibração no cabo, com flexão na viga desprezável) e primeiro modo à torção. O modelo foi reduzido a três graus de liberdade. A modelagem dos carregamentos aerodinâmicos aplicados na viga foi feita segundo procedimentos tradicionais. O carregamento aerodinâmico aplicado ao cabo sob efeito de chuva e vento também foi levado em consideração. Para a redução do modelo matemático, os coeficientes de rigidez e de amortecimento equivalente são definidos e dependem parametricamente da velocidade do vento. Os termos não-lineares são devidos ao acoplamento das vibrações do cabo e da viga à flexão (no plano do cabo) e também aos efeitos aeroelásticos no cabo. Os seguintes regimes instáveis são avaliados: o efeito de galope (galloping) no cabo, o drapejamento (flutter) unimodal na torção e o drapejamento (flutter) do modo de flexão da viga em conjunto com vibrações transversais do cabo. / This paper is concerned with determining wind critical velocities and post-critical vibration amplitudes in a cable-stayed beam, under wind-rain condition. It is considered the cable sag due to the dead load plus the non-linear coupling between the vibration of both the cable and the beam. Three modes are of special interest, namely the first global mode (beam bending & cable vibration), the first local mode (cable vibration & negligible beam bending) and the first torsion mode. A reduced mathematical model, with three degrees of freedom, is also developed. With regard to the modelling of the aerodynamic loads applied to the beam, it can be performed after extension of classical guidelines. The aerodynamic loads applied to the cable under rain are also taken into account. For the reduced mathematical model, equivalent damping and stiffness coefficients will be defined, which depend parametrically on the wind velocity. Non-linear terms appear due to the coupling between the cable and the beam bending vibrations, and also to the aero-elastic non-linear effects on the cable. Different unstable regimes are surveyed such as the cable galloping, the unimodal flutter in torsion and the unimodal flutter with beam bending and cable vibrations coupled.

The diploma thesis deals with design and assessment of pedestrian and bicycle footbridges across the river Moravia in Olomouc. The main material used in the design is S355 steel. At the beginning of the thesis, two variants are compared, from which one is subsequently selected for a more detailed design and assessment. The main supporting element of the selected variant are two parabolic arcs inclined to one another, on which the coupling of the intermediate bridge is suspended by means of the rods. The construction span is 54m.

The subject of this master thesis is a design of a bridge for pedestrians and cyclists across the river Morava in Olomouc. Within the scope of thesis there are 3 studies of bridges. Cable-stayed bridge with prestressed spine beam was found appropriate and further calculations were assessed. Static calculations of prestressed spine deck and reinforced concrete pylon were made. Eigen frequencies and modes of construction were obtained. Internal forces were provided by SCIA Engineer with effect of non-linear parameters. Calculations were made according to valid standards and regulations.

The content of this diplom is about design and assesment of a steel footbridge for pedestrians and cyclists across the river Ostravice. In an introduction of the work are compared two possible options of footbridge structures.and then the appropriate one is processed in detail. The chosen variant is made of two parabolic arches tilted to each other on which is suspended deck by suspenders. In a static aspect the main loadbearing beams are two-hinged arches. The bridge deck consists of two steel beams and floor beams which are composited with a reinforced concrete slab. The span length is 80 m and archs camber is 9,12m. The main material of the structural elements is steel S355.