Dissertations / Theses on the topic 'Prestressed'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Prestressed.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Davis, Brent M. "Evaluation of prestress losses in an innovative prestressed precast pavement system." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4516.
Full textThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 22, 2007) Includes bibliographical references.
Xiang, Ziru. "Synergic identification of prestress and moving forces for prestressed concrete bridges." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/116900/1/Ziru_Xiang_Thesis.pdf.
Full textHodges, Hunter Thomas. "Top Strand Effect and Evaluation of Effective Prestress in Prestressed Concrete Beams." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/36300.
Full text
The second objective of this thesis was to compare experimentally measured prestress losses to theoretical calculations. Theoretical prestress losses were calculated according to PCI and AASHTO Refined methods. These methods produced similar results. Prestress losses were experimentally measured by vibrating wire gages and flexural load testing. Vibrating wire gages were used to monitor internal concrete strains. Two methods were used to reduce vibrating wire gage data: an upper/lower bound method and a basic method. The upper/lower bound method produced distorted data that was unreasonable in some cases. The basic method was more reasonable, but resulted in some prestress loss measurements that were greater than theoretical predictions. Flexural load testing was used to back calculate prestress losses from crack initiation and crack reopening loads. Prestress losses measured by crack initiation loads were generally greater than theoretical values. Losses measured by crack reopening loads were distorted. The distortion was attributed to difficulty in isolation of the correct crack reopening load. Large measurements of prestress losses by the basic vibrating wire gage and crack initiation methods suggested that losses occurred between the time when concrete was poured and prestress transfer occurred. Such losses are not accounted for in current code provisions. More research is recommended to determine the magnitude of these additional losses and their effect on design.
Master of Science
Hussin, Manal Kamil. "Identification of prestress force in prestressed concrete box girder bridges using ultrasonic technology." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/117669/8/Manal_Hussin_Thesis.pdf.
Full textAli, Hussam A. "Corrosion in prestressed concrete." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79993.
Full textDuring the corrosion period, various electrochemical tests were performed to monitor the corrosion activity as a function of elapsed time. Strains at selected locations were measured regularly to check the instantaneous level of prestress. At the end of the experiment, the prestressing strands were removed from the concrete, visually inspected, and weighed. They were also tested in tension to determine their residual tensile strength and their mode of failure.
An assessment of the electrochemical results did not point to any relationship between the initial levels of prestress and the corrosion activity. A similar observation was made in verifying the effect of the initial level of prestress on the corrosion activity as manifested in the residual tensile strength of the strands or their final measured weights.
This research program was therefore valuable to the practicing engineer in the design and maintenance of durable prestressed concrete structures. The findings confirmed that the risk and extent of corrosion in all prestressing strands in corrosive environments are roughly similar, regardless of the initial prestressing level.
Nicklisch, Arndt W. 1975. "Adaptively prestressed concrete structures." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9144.
Full textIncludes bibliographical references (leaves 93-96).
Passive structures react effectively to only one dominant loading condition. Adaptive structures in contrast can deal with multiple loading conditions and unanticipated events at the same time. Truly adaptive civil structures do not exist. Concrete structures can be made adaptive through variable prestressing. Design concepts for an adaptive prestressed concrete girder are formulated in this research. Loading conditions and desired capabilities of the proposed system are defined. The system architecture is composed of sensors, a monitoring and control scheme, and actuators. These system components perform state identification, decision-making, and implementation of actions. Each system component is assigned requirements that are necessary to deal with all loading conditions in an appropriate way. Existing sensor technologies are explained and evaluated with respect to their capabilities to fulfill their functional requirements. A monitoring scheme is designed to interpret data assessed by the sensors for state identification. Adaptive control systems cannot be designed with conventional control algorithms. New control decision systems such as neural nets, expert systems, and fuzzy logic systems are needed for this task. Here, these systems are presented in general as forms of adaptive control. For each loading condition of the proposed system, a control strategy is developed. For the control of fluctuating live loads, a fuzzy logic based control scheme is proposed. Criteria for the selection of actuator technologies are given, and candidate actuator technologies are described and evaluated. Lastly, the problems associated with integrating the system components into a single system are discussed.
by Arndt W. Nicklisch.
S.M.
Pathirage, Thisara Shamane. "Identification of prestress force in prestressed concrete box girder bridges using vibration based techniques." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/112767/1/Thisara%20Shamane_Pathirage_Thesis.pdf.
Full textHuthman, Ibrahim O. "3D Printing for Prestressed Concrete." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1483544593929285.
Full textUmakanthan, Saravanan. "Mechanics of prestressed and inhomogeneous bodies." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4241.
Full textMatthews, Debra Sue. "Blast effects on prestressed concrete bridges." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Summer2008/D_Matthews_072908.pdf.
Full textWang, Zhongsheng. "VIbration behaviour of prestressed concrete beams." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420369.
Full textCarroll, B. C. "Behaviour of prestressed grout bond joints." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/38255.
Full textSivanendran, Shobana. "CFRP prestressed concrete exposed to moisture." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/270196.
Full textRuiz, Meléndez Sergio 1974. "Dynamics of prestressed concrete railway bridges." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/84298.
Full textIncludes bibliographical references (leaves 80-81).
by Sergio Ruiz Meléndez.
M.Eng.
Zafer, Algahtani Nabeel Al. "Pocket-type prestressed brickwork retaining walls." Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/11666.
Full textLai, Hoke Sai. "Partially prestressed concrete internal square panel." Thesis, University of Leeds, 1986. http://etheses.whiterose.ac.uk/301/.
Full textAngomas, Franklin B. "Behavior of Prestressed Concrete Bridge Girders." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/405.
Full textMuller, John Francis. "Serviceability of prestressed concrete railway sleepers." Thesis, Queensland University of Technology, 1985. https://eprints.qut.edu.au/36475/1/36475_Muller_1985.pdf.
Full textLindley, Seth Michael. "Investigation of the Time-Dependent Longitudinal Flexural Behavior of the Varina-Enon Bridge." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/92799.
Full textMaster of Science
Post-tensioned concrete is a building technology which provides a compressive force to concrete via steel tendons. This combination of steel and concrete allows for the construction of lighter and stiffer structures. Post-tensioned concrete is widely utilized throughout the United States highway system and bridge construction. Over time, the force in the prestressing strands is reduced by delayed strains in the concrete. The accurate estimation of this prestress loss is vital for making good decisions about the remaining capacity of a structure and the infrastructure system at large. The Varina-Enon Bridge is a post-tensioned concrete box-girder bridge in Richmond Virginia. Cracks in the bridge prompted an investigation into the magnitude of prestress loss experienced by the structure. To estimate prestress loss, a computer model of the structure was created. In addition, data from sensors previously installed on the bridge were used to back calculate prestress loss. It was found that the estimation of losses from the field closely matched those estimated at the construction of the bridge. Additionally, more updated loss models estimated similar, or slightly smaller values for prestress loss.
Nassar, Adil J. "Investigation of Transfer Length, Development Length, Flexural Strength and Prestress Loss Trend in Fully Bonded High Strength Lightweight Prestressed Girders." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/32941.
Full textMaster of Science
Osborn, Parry. "Ultimate Shear Capacity and Residual Prestress Force of Full-Scale, Forty-One-Year-Old Prestressed-Concrete Girders." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/591.
Full textXu, Jiangong Barnes Robert W. "Nondestructive evaluation of prestressed concrete structures by means of acoustic emissions monitoring." Auburn, Ala, 2008. http://hdl.handle.net/10415/1429.
Full textTso, Karmen. "Full-range behaviour of concrete beams partially prestressed with unbonded tendons." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38225578.
Full textGosaye, Fida Kaba Jonathan. "Behaviour and design of prestressed steel structures." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/34395.
Full textEl, Metwally Ahmed Salah. "Prestressed composite girders with corrugated steel webs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0006/MQ38626.pdf.
Full textElfergani, Hisham. "Acoustic emission analysis of prestressed concrete structures." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/49383/.
Full textChan, Andrew Kay Ching. "Impact behaviour of model prestressed concrete beams." Thesis, University of Sheffield, 1986. http://etheses.whiterose.ac.uk/3484/.
Full textRoumani, N. A. "The shear strength of prestressed brickwork sections." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374836.
Full textBuchner, Susanne. "Full scale testing of prestressed concrete structures." Thesis, University of Surrey, 1989. http://epubs.surrey.ac.uk/804425/.
Full textMontague, T. I. "Concrete blockwork diaphragm walls - prestressed and unprestressed." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293672.
Full textARAUJO, RICARDO RODRIGUES DE. "STRUCTURAL BEHAVIOUR OF PRESTRESSED STAYED STEEL COLUMNS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=31841@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE EXCELENCIA ACADEMICA
Colunas de aço estaiadas e protendidas são conhecidas como excelente solução em escoramento de grandes estruturas, como colunas de coberturas de lonas tensionadas, etc. Este trabalho apresenta uma série de ensaios experimentais tridimensionais em escala real desenvolvidos para determinação do comportamento estrutural de colunas de aço estaiadas e protendidas. Foram estudadas as variações no nível de protensão e na rigidez dos estais, além de descrever como os ensaios experimentais das três colunas de aço estaiadas são realizados: compreendendo os materiais utilizados; um novo sistema de medição de força nos estais; os passos e dificuldades na montagem das três colunas e o sistema de protensão aplicado. Existem alguns parâmetros que influenciam diretamente na resistência dessas colunas estaiadas, como por exemplo, a altura da coluna, o diâmetro externo, entre outros. Devido ao comportamento complexo deste tipo de colunas e ao grande esforço computacional para simulação do comportamento estrutural, através de uma análise paramétrica, optou-se por utilizar um projeto de experimentos junto com redes neurais a fim de extrapolar e obter novos resultados para carga crítica do sistema estrutural sem a necessidade de análise por programas de elementos finitos. De forma a complementar a tese, realizou-se um estudo do comportamento do sistema estrutural sujeito a ações dinâmicas através do programa de elementos finitos ANSYS com o objetivo de determinar as frequências naturais associadas aos seus modos de vibração. Também foi estudada a aplicação de um carregamento súbito para determinação do fator de amplificação dinâmico da coluna de aço estaiada e protendida.
Prestressed steel columns are known as an efficient structural solution for great variety of temporary or permanent supporting systems for large span spatial frames and tensile surface structures. This work presents of full-scale three-dimensional tests carriedout for the assessment of structural behaviour of prestressed stayed steel columns. It was studied the effect prestress force level, stiffness of column braces and stays. Test setup and a new force measuring system for the column stays is fully described. Prestressed stayed steel columns have their strength dependant of parameters like: length, hollow section diameter, brace length and stiffness and axial stiffness of stays. Due to the complex behaviour of such columns that demands great computational effort for numerical simulations required for a parametric analysis it was used an experiment design tool coupled with neural network techniques employed to generate new data for the prestressed column buckling load. A study of the dynamic behaviour of prestressed columns using the finite element package ANSYS was carried-out in order to determine the column natural frequencies and their associated vibration modes. It was also studied the application of sudden loads to determine the dynamic amplification factor of this type of prestressed stayed steel column.
IUNES, YVELYNE BIANCA FERREIRA. "OPTIMUM TENDON PROFILES IN PRESTRESSED CONCRETE BEAMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1998. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=1402@1.
Full textUNIVERSIDADE FEDERAL DO PARÁ
O presente trabalho contém a formulação, implementação e teste de um modelo para determinação do traçado ótimo de cabos de protensão, bem como do valor da força de protensão mínima correspondente, em vigas isotáticas e hiperestáticas. Na formulação, será considerado que o cabo de protensão possui um desenvolvimento segmentado em parábolas do segundo grau, onde o comprimento dessas parábolas serão pré- estabelecidos. Serão feitas ainda simplificações em relação à força de protensão e às perdas de protensão. Com a introdução de tais simplificações e com um artifício de mudança de variáveis, estaremos diante de um problema de programação linear, onde as incógnitas do problema serão a força de protensão e os coeficientes dos trechos de parábolas que representam a geometria do cabo. O objetivo desse problema de programação linear, será minimizar o custo da protensão, de forma que algumas restrições, previamente estabelecidas, sejam atendidas. Tais restrições, limitarão a geometria do cabo, uma vez que o mesmo deve ser contínuo, representado por curvas suaves, e estar contido dentro da viga, e limitarão as tensões nos bordos extremos da viga de forma que as Normas Brasileiras NBR 8681, NBR 7197 e NBR 7187 sejam atendidas. Serão considerados diversos casos de carga e as seções de estudo serão pré-definidas. Como resultado do projeto teremos o traçado ótimo de um cabo médio, e a força de protensão mínima P0, onde já estarão incluídas as perdas imediatas. A implementação da formulação foi desenvolvida em linguagem C, padrão ANSI, o que garante que o mesmo código possa ser compilado em computadores diferentes e por compiladores diferentes, facilitando a portabilidade do programa. Para a otimização, foi utilizado o programa comercial LINDO- Linear Interactive and Discrete Optimizer, que permite uma interação com o usuário, é prático e de grande eficiência. Serão testados e analisados quatro exemplos, variando em sua complexidade. Das quatro vigas testadas, uma foi apresentada por Calçada (1993) em seu artigo "Traçado Óptimo de Cabos de Pré-esforço em Pórticos", e as outras três foram projetadas por engenheiros em escritórios de cálculo estrutural. As duas soluções de projeto, a dada pelo programa e a obtida pelos escritórios, são comparadas de modo a validar tanto a formulação como o programa implementado.
This work is concerned with the formulation, implementation and test of a model for determination of the minimum prestressing force and the optimum tendon profile, to prestressed isostatics and hiperestatics beams. It will be considered in formulation, that the prestressing cable has a development segmented in second grade parabolas, in which the length of each one will be predetermined. In addition, simplifications will be considered with regard to the prestressing force and the prestressing losses. With these assumptions and an artifice of variables change, linear programming problem will be obtained, where the variables will be the prestressing force and the parabolas coefficients that represent the cable geometry. The objective of this linear programming problem will be to minimize the prestressing cost, based on some constraints. These constraints will limit the cable geometry, since this one has to be continue, represented for smooth curves and to be inside of the beam, and will limit the stresses at the top and at the bottom fibers of each studied sections according to Brazilian Codes NBR 8681, NBR 7197 e NBR 7187. Different loads cases will be considered and the studied sections will be predetermined. As project result, we will have an optimum tendon medium profile and the minimum prestressing force P0, where the immediate losses will be included. The formulation implementation was developed in "C" language, ANSI standard, which guarantees that the same code can be compiled in different computers and for different compilers, making the program portability easy. For optimization, the commercial program LINDO- Linear Interactive and Discrete Optimizer was used, which allows interaction with the user, is practical and very efficient. Four examples with different complexity will be tested and studied. From four beams tested, one was presented by Calçada (1993) in his paper "Traçado Óptimo de Cabos de Pré-esforço em Pórticos", and the other ones were designed by engineers in structural design offices. The two design solutions, the one given by the program and the other obtained by the offices, are compared in order to validate both the formulation and the program implemented.
El presente trabajo contiene la formulación, implementación y pruebas de un modelo para determinación del trazado ótimo de cables de protensión, bien como del valor de la fuerza de protensión mínima correspondiente, en vigas isotáticas y hiperestáticas. En la formulación, será considerado que el cable de protensión posee un desarrollo segmentado en parábolas de segundo grado, de dimensiones prestablecidas. Se considerarán simplificaciones en relación a la fuerza de protensión y a las pérdidas de protensión. Con la introducción de tales simplificaciones y con un artificio de cambio de variables, estaremos frente a un problema de programación lineal, donde las incógnitas del problema serán la fuerza de protensión y los coeficientes de los intervalos de parábolas que representan la geometría del cable. El objetivo de este problema de programación lineal será minimizar el costo de la protensión, de forma que sean atendidas algunas restricciones, previamente establecidas. Tales restricciones, limitarán la geometría del cable, que debe ser contínuo, representado por curvas suaves, y estar contenido dentro de la viga; y limitarán las tensiones en los bordes extremos de la viga para atender las Normas Brasileiras MBR 8681, MBR 7197 y MBR 7187. Se considerarán diversos casos de carga y las secciones de estudio serán predefinidas. Como resultado del proyecto tendremos el trazado óptimo de un cable medio y la fuerza de protensión mínima P0, donde estarán incluidas las pérdidas inmediatas. La implementación fue desarrollada en lenguaje C, padrón ANSI, que garantiza que el mismo código pueda ser compilado en computadores diferentes y por compiladores diferentes, facilitando la portabilidad del programa. Para la optimización, fue utilizado el programa comercial LINDO - Lineal Interactive and Discrete Optimizer, que permite una interacción con el usuario, es práctico y de gran eficiencia. Se analizaron cuatro ejemplos, variando su complejidad. De las cuatro vigas, una fue presentada por Calzada (1993) en su artículo "Trazado Ótimo de Cabos de Pré-esforzo en Pórticos", y las otras tres fueron projectadas por ingenieros de cálculo extructural. Las dos soluciones del proyecto, la dada por el programa y la obtenida por los ingenieros, son comparadas para evaluar la formulación del modelo y la implemantación del programa.
Gomez, Nicolas M. Eng Massachusetts Institute of Technology. "Design of prestressed, fabric-formed concrete beams." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111507.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 60-62).
Fabric forms and prestressing are both technologies for concrete structures that allow for less material to do more work. This thesis seeks to assess the feasibility and performance of fabric formed, prestressed beams with a keyhole cross-section, while varying parameters such as concrete strength, loading, beam depth, and prestressing force. They are designed for flexure via a sectional method, starting with the critical midspan section, and each section is iterated in an effort to minimize the beam weight. Beam strength and deflections are determined and once met, they are compared to more traditional prestress designs. Such beams are found to be governed primarily by strength criteria, as deflections are found to be minimal. These fabric formed beams can use nearly an identical amount of material as conventional I-beams with a constant cross-section, while requiring a higher prestressing force. Prestressed fabric formed beams are less efficient than an I-beam section, but should not be discounted as a viable element, because of their aesthetic appeal and further potential for optimization.
by Nicolas Gomez.
M. Eng.
Lobato, de Sousa Monteiro de Morais Miguel Nuno. "Ductility of beams prestressed with FRP tendons." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614171.
Full textBrand, W. W. (Willem Wouter). "Reliability assessment of a prestressed concrete member." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52430.
Full textENGLISH ABSTRACT: First-order second-moment structural reliability methods are used to assess the reliability of a prestressed concrete beam. This beam was designed for imposed office floor loads and partitions following the limit states design method as provided for by the applicable South African structural codes, viz SABS 0100-1:1992 and SABS 0160:1989. The reliability is examined at two limit states. At the ultimate limit state of flexure the ultimate moment of resistance must exceed the applied external moment at the critical section, while at the serviceability limit state of deflection the deflection must satisfy the codespecified deflection criteria. Realistic theoretical models are selected to express the flexural strength and deflection of the prestressed concrete member, while appropriate probabilistic models are gathered from the literature for loading, resistance and modelling uncertainties. The calculated reliability index at the ultimate limit state of flexure (3.10) is lower than expected in view of the fact that this represents a non-critical limit state in the case of a Class 2 prestressed concrete member. This condition can be explained with reference to the relatively high uncertainty associated with the modelling error for flexural strength. The calculated reliability index at the serviceability limit state of deflection (l.67) compares well with acceptable practice. The study further focuses on the sensitivity of the reliability at the two limit states of interest to uncertainty in the various design parameters. The ultimate limit state of flexure is dominated by the uncertainty associated with the modelling error for flexural strength, while the contribution to the overall uncertainty of the ultimate strength and area of the prestressing steel and the effective depth is less significant. In comparison the reliability at the serviceability limit state of deflection is not dominated by the uncertainty associated with a single basic variable. Instead, the uncertainty associated with the modelling error, creep factor and prestress loss factor are all significant. It was also demonstrated that the variability in beam stiffness is not a major source of uncertainty in the case of a Class 2 prestressed concrete member. It is recommended that the present code provisions for ultimate strength and deflection should be reviewed to formulate theoretical models with reduced systematic and random errors. The effect of the uncertainty associated with the creep and prestressed loss factors should also be adressed by adjustment of the partial material factor for concrete at the serviceability limit state of deflection. Furthermore, research must be directed towards formulating an objective failure criterion for deflection. The uncertainty in the deflection limit must therefore be quantified with a probability distribution.
AFRIKAANSE OPSOMMING: Eerste-orde tweede-moment struktuur betroubaarheid metodes word ingespan om die betroubaarheid van 'n voorspanbeton balk te bereken. Hierdie balk is ontwerp vir opgelegte kantoor vloerbelasting en partisies volgens die grenstoestand ontwerp metode soos beskryf in die toepaslike Suid-Afrikaanse boukodes, naamlik SABS 0100-1: 1992 en SABS 0160: 1989. Die betroubaarheid word ondersoek by twee grenstoestande. By die swiglimiet van buiging moet die weerstandsmoment die eksterne aangewende moment oorskrei by die kritieke balksnit, terwyl die defleksie die kriteria soos voorgeskryf deur die kode moet bevredig by die dienslimiet van defleksie. Realistiese teoretiese modelle word gebruik om die buigsterkte en defleksie van die voorspanbeton balk te bereken. Verder is geskikte waarskynlikheid modelle uit die literatuur versamelom die belasting, weerstand en modelonsekerhede te karakteriseer. Die betroubaarheid indeks soos bereken vir die swiglimiet van buiging (3.10) is laer as wat verwag sou word in die lig van die feit dat hierdie nie 'n kritieke grenstoestand verteenwoordig in die geval van 'n Klas 2 voorspan element nie. Dit kan verklaar word met verwysing na die relatiewe groot onsekerheid wat geassosieer word met die modellering fout vir buigsterkte. Die berekende betroubaarheid indeks vir die dienslimiet van defleksie (1.67) vergelyk goed met aanvaarde praktyk. Die studie fokus verder op die sensitiwiteit van die betroubaarheid by die twee grenstoestande onder beskouing ten opsigte van die onsekerheid in die verskillende ontwerp parameters. By die swiglimiet van buiging word die onsekerheid oorheers deur die bydrae van die modelering fout vir buigsterkte. Die bydraes tot die totale onsekerheid deur die swigsterkte en area van die voorspanstaal sowel as die effektiewe diepte is minder belangrik. By die dienslimiet van defleksie word die betroubaarheid nie oorheers deur die onsekerheid van 'n enkele basiese veranderlike nie. In stede hiervan is die onsekerheid van die modellerings fout, kruipfaktor en voorspan verliesfaktor almal noemenswaardig. Daar word verder aangetoon dat die veranderlikheid in balkstyfheid nie 'n belangrike bron van onsekerheid in die geval van 'n Klas 2 voorspan element is nie. Daar word aanbeveel dat die bestaande voorskrifte in die kode vir buigsterkte en defleksie aangespreek moet word deur teoretiese modelle met klein modelonsekerhede te formuleer. Die uitwerking van die onsekerheid van die kruip- en voorspan verliesfaktore kan aangespreek word deur 'n aanpassing te maak in die parsiële materiaalfaktor vir beton in die geval van die dienslimiet van defleksie. Navorsing moet verder daarop gemik wees om 'n objektiewe falingskriterium vir defleksie te formuleer. Die onsekerheid van die toelaatbare defleksie moet dus gekwatifiseer word deur 'n waarskynlikheidsverdeling.
Ibell, Timothy. "Behaviour of anchorage zones for prestressed concrete." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259477.
Full textOzel, Alperen. "Seismic Design of a Prestressed Concrete Bridge." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2181.
Full textCojocaru, Razvan. "Lifting Analysis of Precast Prestressed Concrete Beams." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/32464.
Full textMaster of Science
Campbell, Tara. "Prestressed Steel Girders for Two Span Bridges." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690927.
Full textOsofero, Adelaja Israel. "Behaviour and design of prestressed stayed columns." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9589.
Full textMoore, Wendy LeAnn. "Performance of fire-damaged prestressed concrete bridges." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2008. http://scholarsmine.mst.edu/thesis/pdf/Moore_MS_09007dcc806789ec.pdf.
Full textAppendix included as 690 pages at end of thesis. Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed June 8, 2009) Includes bibliographical references (p. 133-138).
Barr, Paul J. "Consistent crudeness in prestressed concrete girder design /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/10128.
Full textDymond, Benjamin Zachary. "Shear Strength of a PCBT-53 Girder Fabricated with Lightweight, Self-Consolidating Concrete." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/35949.
Full textMaster of Science
Chan, Ka-ho Enoch. "Experimental and numerical studies of concrete beams prestressed with unbonded tendons." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40988004.
Full textHui, Macarious Kin Fung. "Anchorage of stirrups in prestressed concrete I-girders." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57783.
Full textApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Taki, Ismail M. "Load distribution in test loaded prestressed concrete piles." Thesis, University of Ottawa (Canada), 1987. http://hdl.handle.net/10393/11090.
Full textDaher, Yehia Mohamad. "Behavior of lightly prestressed members with unbonded tendons." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq22589.pdf.
Full textRashed, Abdelaziz A. "Rational design of prestressed and reinforced concrete tanks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq29097.pdf.
Full textMiltenburg, Roger J. "Membrane behaviour in one-way prestressed concrete slabs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/MQ30752.pdf.
Full textSuh, Kwangsuk. "Underwater FRP repair of corrosion damaged prestressed piles." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001601.
Full text