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1
Hashemidehaghi, Sogol. "The Isfahan's inhabited arch bridges." Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/27681.
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Ispahan est l’une des villes historiques qui se trouve au centre d'Iran. La ville est célebre pour sa belle architecture islamique. ses ponts couverts, ses mosquées uniques et ses minarets. Cela a fait d'lspahan le titre de "la moitié du monde " dans la culture populaire. Les cinq ponts historiques Zayandeh Rud à lspahan sont un chef-d'oeuvre de l'architecture iranienne, conçus non seulement pour le passage des individus. mais aussi pour traverser les confins de ce monde. la compréhension des valeurs matérielles et imnmatérielles existant dans les ponts historiques d'Ispahan afin. deles protégeres l’un des objectifs principaux de cette thèse. La compréhension des techniques de construction des ponts-arcades à lspahan et ses changements au fil du temps est autre buts de cette recherche qui montre l'intelligence et les talents des lraniens dans la construction de ponts. non seulement en tant que lieu de passage. mais également en tant que lieu de réflexion, de divertissement et de rassemblement, ainsi qu'une structure technique telle que barriêre permettant de contrôler l'écoulernent d'eau;
Abstract: lsfàhan is one of the historic cities in the center of lran. This city is the third most populated city of lran which is also rich in history, art and architecture. The largest river of lranian Plateau in central part Iran which name is Zayandeh-Rud also crosses Isfahan and from the past to the present day, this river played an important role in the formation of the civilization and development of the city of lsfàhan. Therefore, due to the constant development of Isfahan throughout history, as well as the existence of a Zayandeh-Rud flow, numerous bridges were built with a various function in this city. These bridges were designed to connect water, wind, nature and the human being in a particular architectural concept. They were not just designed for passage of the individuals or just for connecting two banks of river, but their purpose was also to link spiritual advancernent and human understanding. They have been designed in the way which makes the pedestrians to stay, watch the beauty of nature, listen to it and think. Since the Isfahan’s bridges have different functions, they can be categorized into inhabited bridges.
2
Ng, Kwooi-Hock. "Analysis of masonry arch bridges." Thesis, Edinburgh Napier University, 1999. http://researchrepository.napier.ac.uk/Output/3673.
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In January 1999, the maximum axle weight increased from IN to 11.5t for the assessmenot f highway bridges and structures. At the samet ime, the maximum vehicle weight also increased from 38t to 44t. Highway authorities are urgently searching for a more refined assessmenmt ethod to predict the behaviour of masonry arch bridges. LUSAS finite element analysis was used to study the behaviour of masonry arch bridges. Load versus deflection curves and collapse loads are given for some of the full and large scale arches previously tested to collapse. A parametric study was also performed to determine the influence of the arch material properties and the load dispersal angle: the arch tensile strength and the load dispersal angle were found to have the most significant influence on the collapse load predictions. Repeatability tests were carried out by building three nominally identical large scale arch bridges in the laboratory and testing them to collapse. The first, second and third arches collapsed at 2lkNm', 16kNm', and 25kNm 1 respectively. Finite element analysis predicted a range of 18kNm' to 39kNm 1 for the same arches. This led to an examination of a statistical, risk based, approach to bridge assessment. Two novel risk assessment programs were developed by integrating Monte Carlo simulation with the MEXE and the mechanism methods. Statistical information about the predicted collapse load and allowable axle load is given. These risk assessment tools are offered for incorporation within routine assessmenmt ethods. Their principal benefit lies in providing engineers with a feel for the reliability of their analyses. A modification has been made to the mechanism method by considering arch deflection. A mechanism prediction is accurate only when all the forces and their positions are accurately located. The modified mechanism method was used to analyse some of the full scale arch bridges, previously tested to collapse, which revealed that arch deflections had a significant influence on the collapse load prediction.
3
Palaoro, Stefania. "Arch bridges: Design - Construction - Perception." Doctoral thesis, Università degli studi di Trento, 2011. https://hdl.handle.net/11572/367845.
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The arch bridges have an historical development, that is rooted in their ancient tradition, yet are also very successful to this day, a rediscovery of the earliest arched forms can be seen in the most recent innovations. After millennia of masonry arch bridges and almost two centuries of relentless development of iron, steel and concrete arch bridges, with different structural schemes and constructive shapes, there was a moment that this type of structure was bound to disappear.
The scope of traditional arch bridges, which refers mainly to the ones of small and medium span, was to become the uncontested role of the girder bridges. The reuse and the assertion of the arch bridge has been accompanied by a strong architectural emphasis on their structural design and constructive details. This relation, increasingly important during the design phase between the concept of FORM and of STRUCTURE, has ensured that many new projects link the strong relationship between TRADITION and technological and constructive INNOVATION.
I ponti ad arco sono quelli che presentano un’evoluzione storica che fonda le sue radici nella tradizione più antica, ma anche quelli che ricevono all’oggi il maggior successo, una riscoperta delle prime forme arcuate che ritornano quasi come una moda ma con l’impiego delle recenti innovazioni: dopo millenni di ponti ad arco in muratura e quasi due secoli di inarrestabile sviluppo di ponti ad arco in ghisa, di ferro, acciaio e di cemento armato, accompagnato da diversi schemi strutturali e di forme costruttive, sembrava che questa tipologia fosse destinata a scomparire. Infatti il campo tradizionale dei ponti ad arco che si riferiva soprattutto ai ponti di media luce era divenuto oramai dominio incontrastato dei soli ponti a travata. Il riuso e il riaffermarsi del ponte ad arco è stato accompagnato da una forte accentuazione architettonica della loro concezione strutturale e dei loro dettagli costruttivi. Il rapporto sempre più importante in fase progettuale di correlare il concetto di FORMA con quello di STRUTTURA ha fatto in modo che molte nuove opere d’arte di nuova realizzazione unissero in sé il forte rapporto tra TRADIZIONE e INNOVAZIONE tecnologica e costruttiva.
4
Palaoro, Stefania. "Arch bridges: Design - Construction - Perception." Doctoral thesis, University of Trento, 2011. http://eprints-phd.biblio.unitn.it/504/1/Stefania_Palaoro_Arch_bridges%2Cdesign-construction-perception.pdf.
Full textAbstract:
The arch bridges have an historical development, that is rooted in their ancient tradition, yet are also very successful to this day, a rediscovery of the earliest arched forms can be seen in the most recent innovations. After millennia of masonry arch bridges and almost two centuries of relentless development of iron, steel and concrete arch bridges, with different structural schemes and constructive shapes, there was a moment that this type of structure was bound to disappear.
The scope of traditional arch bridges, which refers mainly to the ones of small and medium span, was to become the uncontested role of the girder bridges. The reuse and the assertion of the arch bridge has been accompanied by a strong architectural emphasis on their structural design and constructive details. This relation, increasingly important during the design phase between the concept of FORM and of STRUCTURE, has ensured that many new projects link the strong relationship between TRADITION and technological and constructive INNOVATION.
I ponti ad arco sono quelli che presentano un’evoluzione storica che fonda le sue radici nella tradizione più antica, ma anche quelli che ricevono all’oggi il maggior successo, una riscoperta delle prime forme arcuate che ritornano quasi come una moda ma con l’impiego delle recenti innovazioni: dopo millenni di ponti ad arco in muratura e quasi due secoli di inarrestabile sviluppo di ponti ad arco in ghisa, di ferro, acciaio e di cemento armato, accompagnato da diversi schemi strutturali e di forme costruttive, sembrava che questa tipologia fosse destinata a scomparire. Infatti il campo tradizionale dei ponti ad arco che si riferiva soprattutto ai ponti di media luce era divenuto oramai dominio incontrastato dei soli ponti a travata. Il riuso e il riaffermarsi del ponte ad arco è stato accompagnato da una forte accentuazione architettonica della loro concezione strutturale e dei loro dettagli costruttivi. Il rapporto sempre più importante in fase progettuale di correlare il concetto di FORMA con quello di STRUTTURA ha fatto in modo che molte nuove opere d’arte di nuova realizzazione unissero in sé il forte rapporto tra TRADIZIONE e INNOVAZIONE tecnologica e costruttiva.
5
Wang, Xin Jun. "Failure criterion for masonry arch bridges." Thesis, University of Dundee, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318150.
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Ellick, Jane Caroline Ann. "Vibration characteristics of masonry arch bridges." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262545.
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Msaaf, Khaoula. "Multi-Objective optimization of arch bridges." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111519.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 83-84).
Trussed arch bridges are commonly used to attain big spans. They are efficient structures that offer a wide range of geometries, materials, and topologies. This thesis studies the influence of the geometry and topology of arch bridges on both their structural performance relayed by the maximum deflection and their structural weight. Various materials are also considered to calculate the embodied carbon emission and investigate the environmental impact of arch bridges. Gustave Eiffel's Garabit Viaduct is used as a design precedent for this study. 2-D and 3-D parametric models of the arch bridge are realized using Grasshopper [8]. Changing the geometric parameters in addition to the topology enables the investigation of the bridge's performance. The cross sections are automatically optimized in each case. Furthermore, a multi-objective optimization process was run on the bridge to examine the tradeoffs between the deflection and the self-weight. The weight-oriented optimization allows saving more than 60% of the weight compared to the original structure. Analyzing the different resulting designs proves that increasing the depth at the arch's crown and the depth at the base of the arch leads to better deflection results. It also demonstrates that using a denser truss structure leads to a lighter structure.
by Khaoula Msaaf.
M. Eng.
8
Wu, Lufang. "Serviceability assessments of masonry arch bridges." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55010/.
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Masonry arch bridges continue to play an important role in the UK's transport infrastructure, forming a significant proportion of road, rail and waterway crossings. Many of these bridges are relatively old and are still in service in their original configuration. Increasing vehicle loads and speeds have highlighted the need for reliable estimates of both ultimate and serviceability load levels. Most experimental work and assessment methods have so far been carried out under ultimate load. Only limited work has been undertaken to date on serviceability assessment methods, this project therefore aims to develop a systematic method to assess the serviceability load of masonry bridges under a series of different serviceability criteria. A complex spreadsheet was developed as the main analytical tool for the serviceability assessment and was an encastered elastic analysis based on Castigliano's complementary energy method. The geometric data from a large number of real masonry bridges data was gathered and analysed to develop suitable distribution statistics. Three independent serviceability criteria were then developed based on an attempt to replicate, on average, the existing assessment methods. These three criteria are stress, deflection and cracking depth. Finally, a serviceability assessment method system was fully established within the developed spreadsheet.
9
Fairfield, Charles Alexander. "Soil-structure interaction in arch bridges." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/13809.
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European Community directives now insist upon the imposition of 11.5t axle weights for the assessment of highway bridges and structures. This need for heavier loads arises from the Community wide harmonisation of transport policy. Its successful implementation requires the urgent assessment of our bridge stock of some 75000 masonry arches. The analysis of arch bridges has long lacked an accurate method of assessing the loads transmitted to the arch ring by the surrounding soil. This thesis proposes pressure distributions suitable for use in the analysis of arch bridges. It examines, by way of instrumented small scale and in-situ tests, the soil-structure interaction effects arising from the backfill material. Observations of zones of soil displacement around a loaded arch are made in order to better describe the interactive effects. A finite element analysis of the instrumented tests was done and a parametric study was used to assess the effects of various material properties upon the system's behaviour. The inclusion of the interactive effects observed, and modelled, intends to lead to cost savings in the arch bridge assessment programme by reducing the conservatism inherent in the most common assessment methods. Design curves incorporating soil-structure interaction effects are presented where significant capacity increases can be seen compared with analyses ignoring the effects.
10
Callaway, Phillip Arthur. "Soil-structure interaction in masonry arch bridges." Thesis, University of Sheffield, 2007. http://etheses.whiterose.ac.uk/3036/.
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Gong, Nai-Guang. "Finite element analysis of masonry arch bridges." Thesis, University of Nottingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335791.
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Hodgson, J. A. "The behaviour of skewed masonry arch bridges." Thesis, University of Salford, 1996. http://usir.salford.ac.uk/27332/.
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Masonry arch bridges have been used throughout the world. Many thousands exist in Europe. The number of arch bridges in the United Kingdom has been estimated at 75,000 with approximately equal numbers occurring within the road and railway networks. The arch is very pleasing to the eye. Many arch bridges are listed structures so that replacement schemes are not options. In 1880 Baker was commissioned to report on the deterioration of Telford's Bridge at Over. Baker wrote, "The abutments had gradually gone over, and had been continuing to go over for sixty years. The result was that certain barbarians were actually urging the magistrates to take down the bridge...". He continued, "... cracks in the spandrels were big enough to walk through quite comfortably. It would be a disgrace to the country if they pulled down Telford's historical work and substituted a hideous iron latticebridge", (Heyman & Threlfall, 1973). Masonry arch bridges were built to carry a road, a railway or sometimes a waterway over an obstacle. A right arch bridge was used where the crossing could be perpendicular to the obstacle. In contrast, a skewed arch was built wherever the obstacle and over-road intersected at any angle other than 90°. Thus, a right arch is a special case of the more general class of skewed arch. The extent of existing knowledge of the behaviour of arch bridges is limited to the right arch in which many effects have either been omitted or have been simplified. These effects include the spandrel walls, the backfill, irregular geometry, and eccentric loading. Clearly, there is scope for an advancement of knowledge so that these effects may be considered and ultimately the behaviour of the skewed arch bridge can be described. The construction of arch bridges in Great Britain reached its zenith at around the beginning of the Nineteenth century. At this time, if conditions prevailed, there was a general desire for each new bridge to exceed the span of any that had gone before (Ruddock, 1979). However, Sejourne (1913) could only find eight structures in the United Kingdom that had at least one span with a clear opening of more than 40.0 m.
13
Colla, Camilla. "Non-destructive testing of masonry arch bridges." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/12165.
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Stone masonry arch bridges form a critical part of the transportation system. Present methods of assessment are sometimes too conservative and a number of bridges fail the assessment even though they appear in good condition. Non-Destructive Testing can play a key role and three Non-Destructive techniques - radar, sonics and conductivity measurements- are proposed for bridge testing with the aim of obtaining structural dimensions, material characteristics and integrity information which would lead to a more accurate assessment of the structural conditions being made. After discussing problems and limitations with current analytical and load testing methods of assessment, a review of archetypal forms of bridge construction methods employed along the centuries ismade, showing that a greater variety of bridges than commonly believed, exists. The review also enables an Engineer to have some indication of construction type relating to the area, era and designer. The work then includes site work on two masonry bridges and laboratory experiments. On site, the three Non-Destructive Techniques mentioned were used for testing two Scottish stone masonry bridges (one with a brick arch ring) with the aim of obtaining information about the condition and nature of the materials in the fill, the internal configuration of the structure and the geometrical dimensions of the elements. Data from each technique were plotted in the form of cross-sectional tomographic maps and the results interpreted and compared. Limitations are also discussed. In the laboratory, experiments with radar were undertaken to calibrate the technique in controlled conditions and also, and more importantly, to obtain information about phenomena of signal behaviour and material properties as would be found in a masonry arch bridge. The findings served the purpose of aiding a better planning of radar surveys to be made and an improved understanding and interpretation of the radar data to be obtained.
14
Robinson, Justin. "Analysis and assessment of masonry arch bridges." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/12876.
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The importance of masonry arch bridges to the transport infrastructure throughout Europe is unquestionable. However with the ever increasing axle loads present on today's roads, and new European directives increasing the required load carrying capacity, the need for an accurate and reliable method of arch bridge assessment has never been more important. The current methods of arch bridge assessment have been shown to be conservative resulting in unnecessary and costly repair work or replacement of structures. The research described in this thesis is an element of an on-going study into soil-structure interaction, a very important factor for the accurate assessment of arch bridges. This overall investigation, continuing study into the effects of soil-structure interaction, is undertaken with a variety of methods and techniques. These include model bridge testing investigating different load types and fill heights, monitoring of full scale structures and subsequent analysis investigating thermal effects, comparison of the present arch bridge assessment methods linked with an actual arch bridge assessment program and the development of new numerical modelling models of arch assessment. Thus an investigation using discrete element analysis methods has been conducted, with comparison with finite element methods and physical models.
15
Zhang, Yanyang. "Advanced nonlinear analysis of masonry arch bridges." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/29128.
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This research investigates the nonlinear response up to collapse of masonry arches and arch bridges using advanced numerical descriptions. Past research has shown that the mesoscale modelling approach for brick-masonry, where bricks and mortar joints are modelled separately, may offer a realistic representation of the mechanical behaviour of masonry components. However, because of the significant computational cost, thus far the use of this modelling strategy has been mainly restricted to 2D analysis of masonry arches and arch bridges. In some cases this may lead to a crude representation of the response which is inherently three-dimensional, especially when the analysed structure is subjected to eccentric loading or is characterised by a complex geometry (e.g. skew arches). In this work, masonry arches and arch bridges are analysed using a partitioned mesoscale approach, which enables the use of a detailed model for describing material nonlinearity at structural scale. This is combined with a partitioned approach allowing for parallel computation which guarantees computational efficiency. In the 3D mesoscale description, brick units and mortar interfaces are modelled separately accounting for the actual texture and arrangement of masonry. 3D elastic continuum solid elements are used to model brick units while mortar interfaces are modelled by means of 2D nonlinear interface elements. In analysing masonry bridges, the backfill material is modelled as an elasto-plastic continuum, while the physical interface between the continuum and mesoscale domain for masonry is represented by nonlinear zero-thickness interface elements allowing separation and plastic sliding. The proposed modelling approach has been applied to the analysis of multi-ring square and skew arches and masonry arch bridges. The numerical results, which also include numerical-experimental comparisons, confirm the accuracy of the adopted numerical strategy. Moreover numerical simulations have been performed to investigate the effects of the arch geometry, loading positions, material characteristics and potential settlements at the supports. The results obtained offer important information and a detailed description on the complex response of these critical structural systems under different loading and boundary conditions.
16
Miri, Mahmoud. "Modelling of repair techniques for masonry arch bridges." Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/55998/.
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Small scale centrifuge models were used to study the behaviour of arches repaired using different techniques. The models under test were 1/12th scale replicas of a 6 metre single span three ring arch. Two types of arch geometry, with span/rise of 4 and 2, were studied as a shallow and deep arch geometry. The models were tested in a centrifuge under a steady equivalent gravity of 12g. Two types of 2-D and 3-D arch models were studied which had the same geometry but different in the addition of spandrel walls. The 3-D models were built with spandrel walls but without any wing walls or parapet. Both 2-D and 3-D arch models were tested under rolling and failure loads. The models were usually tested with fourteen passes of a rolling load and then up to the observation of first signs of failure to enable them to be suitable for applying a repair method. The repaired models were tested using the same procedure but up to the full failure load. To understand the behaviour of the arch models under unsymmetrical loads different roller weights were applied at different positions. The arch deflection and the soil/masonry interaction in arch extrados were measured in all the tests and compared with each other. Plastic mesh reinforcement, stitching, and concrete slab on top of the soil backfill were applied as repair methods to the 2-D arch models. A review of the results has shown an increase in arch stiffness, decrease in deflections and a significant improvement in the ultimate load carrying capacity. A significant effect on the pressure distribution on the arch barrel was observed due to the application of the concrete slab on top of the backfill. Stitching of arch barrel and the barrel to the spandrels, applying partial saddle concrete and strengthening of spandrel wall using reinforced concrete were tested in the 3-D arch models. The results showed improvements in the stiffness and ultimate arch load carrying capacity due to these repair techniques. The results provide a valuable data base for validation of numerical models and an initial attempt to use them with a commercial finite element program is included.
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Gilbert, M. "The behaviour of masonry arch bridges containing defects." Thesis, University of Manchester, 1993. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.574439.
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Zampieri, Paolo. "Semplified seismic Vulnerability Assessment of Masonry Arch Bridges." Doctoral thesis, Università degli studi di Trento, 2014. https://hdl.handle.net/11572/369052.
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This study concerns seismic vulnerability assessment of masonry arch bridges with common typologies in Europe. Bridges are, in most cases, the most vulnerable elements in the transportation network during an earthquake; therefore, their seismic vulnerability assessment is necessary for a proper planning of the emergency phase and to define a priority for retrofit interventions. Masonry arch bridges were subdivided into homogeneous classes of single span and multi-span structures, according to the result of a statistical analysis made up of a large stock of 757 railway bridges located in high seismic areas.
All the different collapse mechanisms for seismic action were studied for each class of masonry arch bridges with application of limit analysis and the calibration with FEM. In particular, limit analysis methods for the seismic assessment of single and multi spans bridges were developed. A innovative limit analysis approach was proposed for the assessment of the global transverse seismic capacity of multi-span masonry bridges with slender piers. Envelope curves representing the seismic capacity expressed in terms of limit horizontal acceleration were derived by parametrical analysis by means of simplified limit analysis. These curves can be used for a simplified vulnerability assessment of masonry arch bridges and for a simple calibration of the judgment obtained by BMS through inspection visits to bridges. In the second part of the study, a new simplified approach for the fast calculation of seismic fragility curves of numerous masonry arch bridge clusters is proposed. The aim of this thesis is to propose a quickly procedure to estimate the seismic vulnerability of extended roadway and railway bridge networks in emergency conditions and to optimize the retrofit interventions.
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Zampieri, Paolo. "Semplified seismic Vulnerability Assessment of Masonry Arch Bridges." Doctoral thesis, University of Trento, 2014. http://eprints-phd.biblio.unitn.it/1257/1/TesiPHD_Zampieri_2.pdf.
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This study concerns seismic vulnerability assessment of masonry arch bridges with common typologies in Europe. Bridges are, in most cases, the most vulnerable elements in the transportation network during an earthquake; therefore, their seismic vulnerability assessment is necessary for a proper planning of the emergency phase and to define a priority for retrofit interventions. Masonry arch bridges were subdivided into homogeneous classes of single span and multi-span structures, according to the result of a statistical analysis made up of a large stock of 757 railway bridges located in high seismic areas.
All the different collapse mechanisms for seismic action were studied for each class of masonry arch bridges with application of limit analysis and the calibration with FEM. In particular, limit analysis methods for the seismic assessment of single and multi spans bridges were developed. A innovative limit analysis approach was proposed for the assessment of the global transverse seismic capacity of multi-span masonry bridges with slender piers. Envelope curves representing the seismic capacity expressed in terms of limit horizontal acceleration were derived by parametrical analysis by means of simplified limit analysis. These curves can be used for a simplified vulnerability assessment of masonry arch bridges and for a simple calibration of the judgment obtained by BMS through inspection visits to bridges. In the second part of the study, a new simplified approach for the fast calculation of seismic fragility curves of numerous masonry arch bridge clusters is proposed. The aim of this thesis is to propose a quickly procedure to estimate the seismic vulnerability of extended roadway and railway bridge networks in emergency conditions and to optimize the retrofit interventions.
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Andersson, Andreas. "Capacity assessment of arch bridges with backfill : Case of the old Årsta railway bridge." Doctoral thesis, KTH, Bro- och stålbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32827.
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The work presented in this thesis comprises the assessment of existing arch bridges with overlying backfill. The main objective is to estimate the load carrying capacity in ultimate limit state analysis. A case study of the old Årsta railway bridge is presented, serving as both the initiation and a direct application of the present research. The demand from the bridge owner is to extend the service life of the bridge by 50 years and increase the allowable axle load from 22.5 to 25 metric tonnes. The performed analyses show a great scatter in estimated load carrying capacity, depending on a large number of parameters. One of the factors of main impact is the backfill material, which may result a significant increase in load carrying capacity due to the interaction with the arch barrel. Based on theoretical analyses, extensive conditional assessments and the demand from the bridge owner, it was decided that the bridge needed to be strengthened. The author, in close collaboration with both the bridge owner and the persons performing the conditional assessment, performed the development of a suitable strengthening. The analyses showed a pronounced three-dimensional behaviour, calling for a design using non-linear finite element methods. Due to demands on full operability during strengthening, a scheme was developed to attenuate any decrease in load carrying capacity. The strengthening was accepted by the bridge owner and is currently under construction. It is planned to be finalised in 2012. The application of field measurements to determine the structural manner of action under serviceability loads are presented and have shown to be successful. Measured strain of the arch barrel due to passing train has been performed, both before, during and after strengthening. The results serve as input for model calibration and verification of the developed strengthening methods. The interaction of the backfill was not readily verified on the studied bridge and the strengthening was based on the assumption that both the backfill and the spandrel walls contributed as dead weight only. The finite element models are benchmarked using available experimental results in the literature, comprising masonry arch bridges with backfill loaded until failure. Good agreement is generally found if accounting for full interaction with the backfill. Similarly, accounting for the backfill as dead weight only, often results in a decrease in load carrying capacity by a factor 2 to 3. Still, several factors show a high impact on the estimated load carrying capacity, of which many are difficult to accurately assess. This suggests a conservative approach, although partial interaction of the backfill may still increase the load carrying capacity significantly.Arbetet i föreliggande avhandling omfattar analyser av befintliga bågbroar med ovanliggande fyllning. Huvudsyftet är att uppskatta bärförmågan i brottgränstillstånd. En fallstudie av gamla Årstabron redovisas, vilken utgör både initieringen och en direkt tillämpning av föreliggande forskning. Kravet från broförvaltaren är att öka brons livslängd med 50 år, samtidigt som axellasten ska ökas från nuvarande 22.5 ton till 25 ton. Utförda analyser visar på stor spridning i uppskattad bärförmåga, beroende på ett stort antal parametrar. En av de främsta faktorerna är fyllningens egenskaper, vilken kan resultera i en markant ökning av bärförmågan p.g.a. samverkan med bågen. Baserat på teoretiska analyser, tillståndsbedömningar och krav från broförvaltaren beslutades att bron skulle förstärkas. En förstärkningsmetod har utvecklats i nära samarbete med broförvaltaren och personer som tidigare utfört tillståndsbedömningarna. Analyserna visar ett utpräglat tredimensionellt beteende, vilket har föranlett användandet av icke-linjära finita elementmetoder. Krav på full trafik under samtliga förstärkningsarbeten har resulterat i att dessa utförs enligt en föreskriven ordning, som ska reducera minskning i bärförmåga under samtliga etapper. Förstärkningsförslaget godkändes av Banverket och är för närvarande under byggnation. Enligt plan ska dessa slutföras under 2012. Fältmätningar har använts för att bestämma det statiska verkningssättet under brukslaster, vilket visas ge goda resultat. Resulterande töjningar från passerande tåg har uppmäts i bågen, både före, under och efter förstärkning. Resultaten har använts både för att kalibrera beräkningsmodeller och att verifiera utförda förstärkningar. Samverkan mellan båge och fyllning har inte kunnat verifierats för den aktuella bron och de utvecklade förstärkningarna baseras på en modell där både fyllning och sidomurar endast utgör yttre verkande last. De framtagna finita element modellerna har jämförts med experimentella resultat från litteraturen, omfattande tegelvalvsbroar med ovanliggande fyllning belastade till brott. Generellt erhålls god överensstämmelse om full samverkan mellan båge och fyllning antas. Om fyllningen istället endast betraktas som yttre last, minskar lastkapaciteten ofta med en faktor 2 till 3. Fortfarande uppvisar ett antal faktorer stor inverkan på bärförmågan, vilka ofta är svåra att med säkerhet bestämma. Ett konservativt betraktningssätt rekommenderas, även om delvis samverkan med fyllningen fortfarande kan öka bärförmågan avsevärt.
QC 20110426
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Geng, Yue. "Time-dependent behaviour of concrete-filled steel tubular arch bridges." Phd thesis, Faculty of Engineering and Information Technologies, 2011. http://hdl.handle.net/2123/8668.
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Sarmiento, Comesías Marta. "Structural behaviour and design criteria of spatial arch bridges." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/327592.
Full textAbstract:
Spatial Arch Bridges (SABs) are defined as bridges in which vertical deck loads produce bending moments and shear forces not contained in the arch plane due to their geometrical and structural configuration. Moreover, the arch itself may not be contained in a plane. A wide compilation of examples of this bridge type has been made. Different benchmarks have been developed to assure the validity of the analysis methods employed in the present research.
An in-depth study of planar and non-planar Inferior Deck Arch Bridges With Imposed Curvature (IDABWIC) has been carried out. In this type of spatial arch bridges the arch and the deck centroid lines are both contained in the same vertical cylinder. The aim of the study is to propose the most appropriate design for controlling the out-of-plane response.
In order to understand the behaviour of these arches, different frame 3D models have been developed and analyzed with commercial software. The arch definition, the deck and arch plan curvature, the arch sag and cross-sections rigidity of arch, deck and hangers, as well as arch cross-section area and different hanger/deck and hanger/arch connection types, have been studied as variables under both symmetrical and asymmetrical vertical loading. Both flexible and rigid hangers have been analysed.
A thorough study for different geometries and boundary conditions at deck abutments of superior deck true SABs under vertical loading and temperature variation has been conducted.
The purpose of the study is to understand the structural behaviour of different geometries of this bridge type and to establish the best boundary conditions at abutments in each case. Vertical planar arch bridges with a curved superior deck are spatial arch bridges (SABs) with a very characteristic structural behaviour and many interesting structural and aesthetic possibilities.
A thorough parametric analysis has been conducted in order to establish efficient values of different parameters for this bridge type according to different criteria. The objective is to minimize the total amount of structural materials.
An appropriate range of values for the different parameters (arch/deck eccentricity, arch rise, arch/deck vertical distance, inclination of struts and the cross-section of the different elements) is given and it is established which parameters are key to the bridge behaviour. The changes in the structural behaviour according to the different parameters are explained.
The stability of SABs with a curved deck is studied and compared with that of planar vertical arch bridges with a straight deck.
For different models of this bridge type geometrically non-linear analyses with and without imperfections have been conducted.
The sensibility to imperfections has also been studied, considering the coded imperfections based on the behaviour of planar vertical arch bridges.
Most SABs are footbridges. Therefore, the dynamic behaviour of this bridge type is an important aspect to be considered. The dynamic behavior of this type of footbridges has been hence also conducted for a SAB example with curved superior deck.Definimos como Puentes Arco Espaciales (PARES) todo puente arco en el que, por su configuración geométrica y estructural, las cargas gravitatorias generan flexiones y cortantes no contenidos en el plano del arco. Además, el propio arco puede no estar contenido en un plano. Se ha llevado a cabo una amplia recopilación de realizaciones de este tipo de puentes. se han desarrollado varios benchmarks para asegurar la validez de los métodos de análisis empleados en la presente investigación. Se ha realizado un amplio estudio de los Puentes Arco de Tablero Inferior con Curvatura Impuesta planos y no planos. En este tipo de puentes arco espaciales el eje del arco y del tablero están contenidos en el mismo cilindro vertical. El objetivo del estudio es proponer el diseño más apropiado para controlar la respuesta fuera del plano del arco. Con el fin de entender el comportamiento de estos arcos, se han desarrollado y analizado diferentes modelos de barras en 3D marco con un software comercial. La definición del arco, de la curvatura del tablero y de la curvatura del arco en planta, la flecha horizontal del arco ceder y la rigidez de las secciones transversales del arco, del tablero y de las péndolas, así como el área de la sección transversal del arco y distintos tipos de conexión péndolas/ tablero y péndolas/arco, se han estudiado como variables bajo tanto carga vertical simétrica como asimétrica en tablero. Se ha considerado el uso tanto de péndolas flexibles como rígidas. Se han estudiado diferentes geometrías y condiciones de contorno en los estribos del tablero para PARES de tablero superior bajo carga vertical y variación de temperatura. El propósito del estudio es entender el comportamiento estructural de distintas geometrías de este tipo puentes y establecer las condiciones de contorno más convenientes en estribos de tablero para cada caso. Los puentes con un arco plano vertical con tablero superior curvo son PARES con un comportamiento estructural muy característico e interesantes posibilidades estructurales y estéticas. Se ha realizado un amplio análisis paramétrico con el fin de establecer valores eficientes para diferentes parámetros en este tipo de puentes de acuerdo con distintos criterios. El objetivo es minimizar la cantidad total de materiales estructurales empleados. Se da un rango adecuado de los valores de diferentes parámetros (excentricidad arco/ tablero, flecha del arco, distancia vertical arco/tablero, inclinación de pilas y la sección transversal de los diferentes elementos) y se establece qué parámetros son fundamentales para el comportamiento de estos puentes. Se explica la influencia de la variación de los distintos parámetros estudiados en la respuesta estructural. La estabilidad de los PARES con tablero se estudia y compara con la de los puentes en arco planos verticales con tablero recto. Se ha llevado a cabo un análisis no lineal geométrico con y sin imperfecciones para diferentes modelos de este tipo puentes. La sensibilidad a las imperfecciones también ha sido estudiada, teniendo en cuenta las imperfecciones estipuladas en los Eurocódigos, basados en el comportamiento de los puentes en arco planos verticales con tablero recto. La mayoría de los PARES son pasarelas. Por lo tanto, el comportamiento dinámico de este tipo puente es un aspecto importante a considerar. Así pues, se ha llevado a cabo un análisis dinámico para un ejemplo PARES con el tablero superior curvo
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Pytlos, Michal. "New tools for modelling soil-filled masonry arch bridges." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/13674/.
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This study is concerned with the development of new numerical and physical tools suitable for modelling soil-filled masonry arch bridges. Firstly, a novel modelling approach is presented which makes use of the Box2D rigid body physics engine, widely used in the computer games industry. A description of the simulation method implemented in Box2D is provided and it is shown that this tool is capable of accurately simulating disc and block interaction dynamics, and can successfully capture the critical state response of granular media. Four Box2D based computer programs, constituting a ‘virtual laboratory’, are presented and are shown to be capable of accurately simulating load tests to failure on both bare and soil-filled masonry arches. It is also demonstrated that the macro-scale properties of a virtual soil material, modelled as an assembly of randomly shaped polygons, are independent of the simulated scenario. Practical issues associated with the use of Box2D as a modelling tool are considered and advantages compared with the traditional distinct element method are discussed. Secondly, an innovative experimental facility developed by the author and suitable for testing medium-scale sand-filled masonry arch bridges is described. The test facility features a novel sand conveyance and pouring system which provides very good control over backfill properties and significantly speeds up the deposition process. Initial test results from the test facility are described and recommendations for future work are made.
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Tao, H. "The behaviour of open spandrel brickwork masonry arch bridges." Thesis, University of Salford, 2003. http://usir.salford.ac.uk/2053/.
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The behaviour of open spandrel brickwork masonry arch bridges (OSBMAB) was studied through model tests and finite element simulations. One three-metre and two five-metre span, full scale OSBMAB were constructed and tested to destruction. Two `partial' models including a combination of spandrel arches and piers, and a five-metre span single arch were also tested with intention of studying the functions of the components of the OSBMAB. To simulate the behaviour of the brickwork masonry arches, three finite element modelling techniques were developed: - (a) smeared modelling method (SMM), in which the failure of brickwork masonry caused by tensile cracking, compressive crushing or sliding is simulated as "loss of stiffness" in the corresponding directions within the domain of the geometry of the arch structure; and (b) discrete modelling method (DMM), in which the failure of brickwork masonry caused by tensile cracking or sliding is simulated as the change in the geometry of the arch structure, i. e., the geometrical discontinuity at prescribed locations; and (c) the mixed modelling method (MMM), in which the main arch, spandrel arches/piers are modelled using the SMM, and the interfaces between the fill and arch are modelled using the DMM. Parametric studies were carried out to investigate the effects of changes in material properties and finite element model related parameters on the behaviour of the OSBMAB, and to justify the values of those parameters adopted in the finite element models using the FE Package ANSYS 5.3. The comparisons were made between the finite element results and those obtained from the model tests. It has been demonstrated in terms of the ultimate loads, the modes of failure and the responses of loads vs. displacements that FE modeling can give good correlation.
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Dorji, Jigme. "Strength and serviceability assessment of aged masonry arch bridges." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/213050/1/Jigme_Dorji_Thesis.pdf.
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This thesis investigated strength and serviceability of aged masonry arch bridges which exist in rail track networks in Australia. The method is based on the measurement of structural responses under operating loads and experimental tests. Two typical bridges were investigated for Australian Rail and Track Corporation Ltd (ARTC) and found that the bridges are safe against the operating loads, despite having undergone aging phenomenon.
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Baker, Martin G. "Finite element analysis of masonry with application to arch bridges." Thesis, Cardiff University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284492.
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Tomor, Adrienn Krisztina. "Internal force distribution in equilibrium analysis of masonry arch bridges." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312418.
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Weston, Daniel Frederick. "Existing and future plans for the structural health monitoring of the Indian River Inlet Bridge." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 248 p, 2006. http://proquest.umi.com/pqdweb?did=1163250401&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Wang, Junzhe. "Numerical modelling of masonry arch bridges : investigation of spandrel wall failure." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629673.
Full textAbstract:
Masonry arch bridges still play an important role in the transportation infrastructure today in the United Kingdom. Previous research has mainly focused on the load carrying capacity in the span direction. The three dimensional behaviour is often investigated by simplifying into two dimensions with modified arch parameters but these simplified analyses cannot represent all aspects of behaviour. Spandrel wall failure in some railway masonry arch bridges has raised concerns recently, and this is one aspect which cannot be modelled in two dimensions. This thesis presents a research which attempts to model the interaction behaviour between arch, backfill and spandrel wall with the aim of representing the three dimensional nature of real bridges. It mainly focuses on the spandrel wall defects under increasing load, including crack development across the wall and longitudinal cracks in the arch barrel underneath spandrel wall. Experimental results from the laboratory tests on engineering blue brick and a hydraulic premixed mortar as well as brickwork masonry specimens are presented. Numerical analysis was initially performed on these brickwork masonry specimens for validation. Three dimensional FE models were proposed for both small and large scale bridges. The general behaviour of the small scale bridge under rolling load and large scale bridge under increasing load were studied. Reasonable agreement between the FE analyses and experimental results from previous literature was obtained, indicating the model validated for small masonry specimens could be scaled up to full-scale bridges. A series of computer models were constructed to investigate the relationship between a range of geometric and material parameters and the lateral behaviour of arch bridges. The backfill depth and spandrel wall thickness have greatest impact on both bridge strength and lateral behaviour. The fill properties also have an importance influence on the load carrying capacity. This provides an indication of which bridge should be more closely monitored for spandrel wall defects. Separate FE models was constructed to simulate existing longitudinal cracks found in the arch barrel for old bridges and the influence of strengthening of spandrel wall with tie bars. The general behaviour under a concentrated load is studied and discussed. It has been demonstrated that it is possible to effectively model the three dimension behaviour of masonry arch bridges and in particular, spandrel wall failures.
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Stuffle, Timothy Jeffrey. "The Indian River Inlet bridge changing from a single rib tied arch to a cable-stayed design /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 4.03 Mb., 278 p, 2006. http://proquest.umi.com/pqdlink?did=1172110651&Fmt=7&clientId=79356&RQT=309&VName=PQD.
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Jayasundara, Walpola Kankanamalage Nirmani. "Damage detection of arch bridges using vibration characteristics and artificial neural network." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/135524/1/Walpola%20Kankanamalage%20Nirmani_Jayasundara_Thesis.pdf.
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This project developed a method to detect, locate and quantify damage in arch bridges using variations in their vibration characteristics and artificial neural network. The method was successfully tested on a few real-life arch bridges. Outcomes of this project will contribute towards the safety of our bridges.
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Prentice, David James. "An appraisal of the geotechnical aspects of multi-span masonry arch bridges." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/12797.
Full textAbstract:
The importance of the masonry arch in Britain's infrastructure has never been more significant especially at the present time under ever increasing axle loads. It is estimated that there are over forty thousand highway arch bridges in the UK alone of which the majority were constructed between the 17th and 19th centuries. As a result of recent European Community directives, a significant proportion of these are required to be reassessed to ascertain their load carrying capacity. The bridge assessment program in the UK is therefore urgent. Current methods of assessment are conservative and often result in unnecessary repair work. Improvements to these methods are now urgently required. This thesis therefore details a continuing study of the effects of the interaction of the soil and the structure on the overall strength of a multi-span arch bridge. The research involves testing of both small and large scale models in an attempt to quantify the effect of the pier on the overall failure load. Both instrumentation and image analysis are used to monitor the dispersal of stress throughout the various models. An assessment of the suitability of using finite element analysis to predict these stresses is also carried out. Finally, the results of a long term monitoring program of a new arch bridge using instrumentation installed during the construction is presented and the effects of seasonal temperature variations are investigated. A new technique for the assessment of arches is subsequently derived which is based on the regression analysis of the tests undertaken for this thesis. It is hoped that the results of this research can be quantified with the long term view of incorporating them in updated assessment methods.
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MANZATO, ANNA. "“MASONRY ARCH BRIDGES IN VENICE: EXPERIMENTAL AND NUMERICAL PROCEDURES FOR STRUCTURAL IDENTIFICATION”." Doctoral thesis, Università IUAV di Venezia, 2020. http://hdl.handle.net/11578/283638.
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Masonry arch bridges are an important part of architectural historical heritage. Their presence is a
characteristic feature of the Italian and European landscape. A large number of research and studies about.
This theme have been produced in literature during time. Regarding Venetian bridges, except for the most
famous architectures. Data are lacking given by research results are lacking.
A procedure for structural identification and for the evaluation of the material mechanical characteristics
for historical masonry bridges is here presented with the aim of their conservation and restoration. The
procedure, based on experimental measurements and numerical analyses, requires, at first, the
measurements of the bridge’s fundamental frequencies, then, through the calibration of bridge FE Model,
allows the estimation of the average materials characteristics. In particular, for the frequency acquisition
data, the procedure proposes the use of a compact digital tromograph, a highly sophisticated measuring
device, equipped with accelerometric and velocimetric transducers, that allows fast and low cost vibration
measurements. Successive analyses, by means of fast Fourier transform, permit to estimate the
fundamental frequency of the structure. For one study case the validity of the results obtained is confirmed
by making a comparison with a measurement campaign performed using accelerometers as instruments.
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Taunton, Paul R. "Centrifuge modelling of soil/masonry structure interaction." Thesis, Cardiff University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244112.
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Nguyen, Dong. "Application of computational limit analysis to soil-structure interaction in masonry arch bridges." Thesis, University of Sheffield, 2009. http://etheses.whiterose.ac.uk/14946/.
Full textAbstract:
For the assessment of Masonry Arch Bridges (MAB), many structural and material models have been applied, ranging from sophisticated non-linear finite element analysis models to much simpler rigid-block limit analysis models. i.e. elastic and plastic methods respectively. The application of elastic analysis to MAB suffers many drawbacks since it requires full mechanical characterization of ancient masonry structures. The mechanical characterization of ancient masonry is difficult since these structures have typically undergone a century or more of environmental deterioration and in many cases have been already subjected to extensive modification. Also, sophisticated material models generally require specialized parameters that are hard to assess, particularly if non-destructive tests are used. In these cases practicing engineers typically favour simpler material models, involving fewer parameters. Thus non-linear finite element methods or other sophisticated models may not be a good choice for the assessment of MAB, while simplified approaches for example based on limit analysis principles are likely to be more appropriate. In this research. a holistic computational limit analysis procedure is presented which involves modelling both soil and masonry components explicitly. Masonry bridge parts are discretized using rigid blocks whilst the soil fill is discretized using deformable triangular elements and modelled a.'i a Mohr-Coulomb material with a tension cut-off. Lower and upper bound estimates of the collapse load are obtained. Results are compared with those from recently performed bridge tests carried out in collaboration with the University of Salford. A key project finding is that the use of peak soil strength parameters in limit analysis models is inappropriate when the soil is modelled explicitly. However, use of mobilized strengths appears to be a promising way forward, yielding much closer correlation with experimental data.
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Thornton, Nathan Paul. "Live Load Testing of Appalachia, Va Concrete Arch Bridges for Load Rating Recommendation." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/35195.
Full textAbstract:
As Americaâ s infrastructure ages, many of the nationâ s bridges approach the end of their service life. In order to develop a method for handling the rising number of deficient and functionally obsolete bridges, nondestructive tests and evaluations must be undertaken. Valuable information from these tests regarding the strength and condition of bridges will help in making decisions about their rehabilitation and replacement. Two adjoining open spandrel reinforced concrete arch bridges in downtown Appalachia, Virginia were selected for live load testing by Virginia Department of Transportation (VDOT). Both bridges have supported an increasing amount of extreme coal truck traffic throughout their service life and are essential to the efficient transport of coal in the region. Because of their age, having been built in 1929, and the amount of visible damage and repairs, VDOT was concerned about their remaining capacity and safe operation.
The live load tests focused on global behavior characteristics such as service strain and deflection as well as local behavior of the arches surrounding significant repairs. It was found that the strain and deflection data collected during load testing displayed linear elastic behavior, indicating excess capacity beyond the test loads. Also, given the loading applied, the measured strains and deflections were small in magnitude, showing that the bridges are still acting as stiff structures and are in good condition.
Data collected during these tests was compared to results from a finite element model of the bridges to determine the coal truck size which is represented by the live load test loading configurations. The model comparisons determined the test loads produced comparable deflections to those produced by the target coal truck load. Through this approach, a recommendation was given to VDOT regarding the satisfactory condition of the aging bridges to aid in the process of load rating and maintenance scheduling for the two bridges.
Master of Science
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Arfelli, Francesco. "Bowstring bridges: static behaviour, critical issues and FEM modelling." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25735/.
Full textAbstract:
The present Master’s Thesis paper is aimed at analysing the fundamental characteristics of the static behaviour of structural arch schemes focusing the attention on two critical issues and their respective practical solutions as applied to a real study case.
After providing a theoretical and historic overview of arches, two crucial aspects of the design phase of an arch bridge have been chosen and discussed. Thus, the construction project of a real structure is taken into consideration with the purpose of discussing a possible solution to the issues highlighted previously.
The study case is identified in the new bowstring bridge crossing the River Enza, in the suburbs of Parma. The static analysis of the structure is carried out comparing the FEM results to the analytical findings.
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Bartolomeo, Veronica <1983>. "Comparison between analytical and numerical methods for the assessment of masonry arch bridges: Case study of Clemente Bridge on Savio river." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4881/1/bartolomeo_veronica_tesi.pdf.
Full textAbstract:
This research has focused on the study of the behavior and of the collapse of masonry arch bridges. The latest decades have seen an increasing interest in this structural type, that is still present and in use, despite the passage of time and the variation of the transport means. Several strategies have been developed during the time to simulate the response of this type of structures, although even today there is no generally accepted standard one for assessment of masonry arch bridges.
The aim of this thesis is to compare the principal analytical and numerical methods existing in literature on case studies, trying to highlight values and weaknesses. The methods taken in exam are
mainly three: i) the Thrust Line Analysis Method; ii) the Mechanism Method; iii) the Finite Element Methods. The Thrust Line Analysis Method and the Mechanism Method are analytical methods and derived from two of the fundamental theorems of the Plastic Analysis, while the Finite Element Method is a numerical method, that uses different strategies of discretization to analyze the
structure. Every method is applied to the case study through computer-based representations, that allow a friendly-use application of the principles explained. A particular closed-form approach based on an elasto-plastic material model and developed by some Belgian researchers is also studied.
To compare the three methods, two different case study have been analyzed: i) a generic masonry arch bridge with a single span; ii) a real masonry arch bridge, the Clemente Bridge, built on Savio River in Cesena. In the analyses performed, all the models are two-dimensional in order to have results comparable between the different methods taken in exam. The different methods have been compared with each other in terms of collapse load and of hinge positions.
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Bartolomeo, Veronica <1983>. "Comparison between analytical and numerical methods for the assessment of masonry arch bridges: Case study of Clemente Bridge on Savio river." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4881/.
Full textAbstract:
This research has focused on the study of the behavior and of the collapse of masonry arch bridges. The latest decades have seen an increasing interest in this structural type, that is still present and in use, despite the passage of time and the variation of the transport means. Several strategies have been developed during the time to simulate the response of this type of structures, although even today there is no generally accepted standard one for assessment of masonry arch bridges.
The aim of this thesis is to compare the principal analytical and numerical methods existing in literature on case studies, trying to highlight values and weaknesses. The methods taken in exam are
mainly three: i) the Thrust Line Analysis Method; ii) the Mechanism Method; iii) the Finite Element Methods. The Thrust Line Analysis Method and the Mechanism Method are analytical methods and derived from two of the fundamental theorems of the Plastic Analysis, while the Finite Element Method is a numerical method, that uses different strategies of discretization to analyze the
structure. Every method is applied to the case study through computer-based representations, that allow a friendly-use application of the principles explained. A particular closed-form approach based on an elasto-plastic material model and developed by some Belgian researchers is also studied.
To compare the three methods, two different case study have been analyzed: i) a generic masonry arch bridge with a single span; ii) a real masonry arch bridge, the Clemente Bridge, built on Savio River in Cesena. In the analyses performed, all the models are two-dimensional in order to have results comparable between the different methods taken in exam. The different methods have been compared with each other in terms of collapse load and of hinge positions.
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Teich, Stephan. "Beitrag zur Optimierung von Netzwerkbogenbrücken." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-86041.
Full textAbstract:
Gegenstand der vorliegenden Arbeit ist die Entwicklung einer optimalen Tragstruktur für Netzwerkbogenbrücken. Dabei wird die systematische Nutzung der Optimierungspotenziale dieses Brückentragwerkes an ausgewählten Tragwerkselementen erarbeitet. Es werden Lösungsvorschläge für die System- und Detailausbildung sowie Berechnungs- und Entwurfsgrundlagen entwickelt. Die Schwerpunkte der Arbeit bilden die Entwicklung von ermüdungssicheren Hängeranschlusskonstruktionen, statisch effizienten Hängernetzen sowie Bögen, die sich durch eine hohe Tragfähigkeit bei gleichzeitig geringem Materialverbrauch auszeichnen. Um eine ausreichende Ermüdungssicherheit der in dieser Hinsicht maßgebenden Hängeranschlusskonstruktionen zu gewährleisten, ist es notwendig, die risserzeugenden Spannungsspitzen zu minimieren und möglichst einen homogenen Spannungsverlauf über das gesamte Bauteil zu erzeugen. Mit Hilfe einer parametergestützten Gestaltoptimierung und anschließender Topologieanpassung wird zunächst eine optimale Lösung für die Hängeranschlusskonstruktion entworfen. Anschließend erfolgt die Entwicklung einer Bestimmungsgleichung für die Kerbwirkungszahl dieser Anschlusskonstruktion, welche die Anwendung des Kerbspannungskonzeptes für Hängeranschlüsse ermöglicht. Zur effizienten Nutzung der statischen Vorteile von Netzwerkbogenbrücken ist die Anordnung der Hänger von großer Bedeutung. Um die vorteilhafteste Hängeranordnung zu ermitteln, werden fünf mögliche Hängernetze mit variierenden Hängerneigungsparametern, Hängeranzahlen und Stützweiten hinsichtlich gezielt ausgewählter statischer Kriterien untersucht und bewertet. Daraus resultierend werden Empfehlungen formuliert, die dem Ingenieur die Wahl eines für entsprechende Rahmenbedingungen geeigneten Hängernetzes erleichtern. Auch die konstruktive Ausführung des Bogens sowie des oberen Windverbandes und das damit verbundene Tragverhalten sind beim Entwurf einer effizienten Netzwerkbogenbrücke von großer Bedeutung. Deswegen wird der Einfluss von Form, Geometrie und Steifigkeit des Bogens sowie von Ausführung und Konstruktion anderer Tragwerksteile auf die Bogenstabilität analysiert. Darauf aufbauend erfolgt die Optimierung dieser Konstruktionsparameter, um die Stahlmasse des Bogens ohne maßgebliche Reduzierung der Tragfähigkeit zu minimieren. Zusätzlich werden verschiedene Ersatzimperfektionen bezüglich ihrer Auswirkung auf die rechnerische Bogenstabilität untersucht und die maßgebenden Vorverformungen hinsichtlich ihrer Form und ihrer Größe herausgestellt. In ausgewählten Beispielen werden abschließend die entwickelten Lösungen mit Bauwerken aus der Praxis verglichen, um die Effizienz des optimierten Tragwerkes zu demonstrierenThis work of research will tackle the development of an optimal structure for network arch bridges. The systematic employment of potentials to optimize these bridge structures will be examined for selected structural members. Suggestions for the construction of the bridge system and of selected details as well as basics for calculation and design will be developed. This paper will focuses mainly on the design of fatigue-proof hanger connections, statically efficient hanger networks as well as arches, which have a high load carrying capacity along with low material consumption. In order to provide sufficient security against fatigue failure for the decisive connections of the hanger bars, stress peaks that cause cracks have to be minimized and homogeneous stress distribution within the whole element has to be ensured. Initially, this paper will delineate an optimal solution for hanger connections by means of parameter-based shape optimization and subsequent topology adaptation. In the following, an analytic formula for the stress concentration factor of this connection will be developed in order to enable the application of the notch stress concept for hanger connections. To apply the static advantages of network arch bridges efficiently, the arrangement of the hangers is essential. In order to determine the most efficient hanger arrangement, five possible hanger arrangements with varying parameters (slope of the hangers, number of the hangers and span of the bridge) will be analyzed and evaluated with respect to systematically selected static criteria. On the basis of these investigations, recommendations for engineers how to choose an optimized hanger arrangement according to different geometrical bridge parameters will be made. Additionally, the constructive design of the arches and the upper wind bracing as well as the associated structural behavior are significant when an efficient network arch bridge is to be designed. For this reason, this paper will analyze the influence of the arch-shape, the arch-geometry and the arch-stiffness as well as the design and construction of other structural members on the stability of the arch. Based on these results, the constructive parameters will be optimized in order to reduce the steel weight of the arch without significantly reducing the load carrying capacity. Furthermore, the influence of different imperfections on the arch stability will be analyzed and the form and size of the decisive initial deflections emphasized. Finally, systematically selected examples will provide a comparison between the developed solutions and existing bridge structures in order to demonstrate the efficiency of the optimized structure
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Hogg, Victoria. "Effects of repeated loading on masonry arch bridges and implications for the serviceability limit state." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362899.
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Brown, Graham. "A study of the effect of damage on the dynamic response of masonry arch bridges." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246045.
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Freedman, Geoffrey J. H. "The development of transversely stress-laminated timber arch bridges for pedestrian and minor vehicle use." Thesis, Edinburgh Napier University, 2006. http://researchrepository.napier.ac.uk/Output/3844.
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Sumon, Sarwan Kumar. "Innovative and effective transport solutions for masonry arch bridges, safety barriers and road humps through testing and numerical simulation." Thesis, University of Ulster, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446253.
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Diamanti, Nectaria. "An efficient ground penetrating radar finite-difference time-domain subgridding scheme and its application to the non-descructive testing of masonry arch bridges." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3491.
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This thesis reports on the application of ground penetrating radar (GPR) as a non-destructive technique for the monitoring of ring separation in brick masonry arch bridges. In addition, research is reported on the assessment of the clay capping layer often used in construction as a waterproof backing to arches. The thrust of the research is numerical modelling, verified by large laboratory experiments. Due to the heterogeneity of these structures, the resultant signals from the interaction between the GPR system and the bridge are often complex and hence, hard to interpret. This highlighted the need to create a GPR numerical model that would allow the study of the attributes of reflected signals from various targets within the structure of the bridge. The GPR numerical analysis was undertaken using the finite-difference time-domain (FDTD) method. Since micro regions in the bridge structure need to be modelled, the introduction of subgrids of supporting finer spatial resolution into the standard FDTD method was considered essential in order to economise on the required computational resources. In the main part of this thesis, it is demonstrated how realistic numerical modelling of GPR using the FDTD method could greatly benefit from the implementation of subgrids into the conventional FDTD mesh. This is particularly important when (a) parts of the computational domain need to be modelled in detail (i.e., ring separation between the mortar layers and the brick units, which is the case studied in this thesis); and also (b) when there are features or regions in the overall computational mesh with values of high relative permittivity supporting propagation of waves at very short wavelengths. A scheme is presented that simplifies the process of implementing these subgrids into the traditional FDTD method. This scheme is based on the combination of the standard FDTD method and the unconditionally stable alternating-direction implicit (ADI) FDTD technique. Given that ADI-FDTD is unconditionally stable, its time-step can be set to any value that facilitates the accurate calculation of the electromagnetic fields. By doing so, the two grids can efficiently communicate information across their boundary without requiring to use a time-interpolation scheme. The performance of ADI-FDTD subgrids when implemented into the traditional FDTD method is discussed herein. The developed algorithm can handle cases where the subgrid crosses dielectrically inhomogeneous and/or conductive media. In addition, results from the comparison between the proposed scheme and a commonly employed purely FDTD subgridding technique are presented. After determination of the optimum ADI-FDTD scheme, numerical experiments were conducted and calibrated using GPR laboratory experiments. Good correlations were obtained between the numerical experiments and the actual GPR experiments. It was shown both numerically and experimentally that significant mortar loss between the masonry arch rings can be detected. Dry hairline delaminations between the mortar and the brick masonry are difficult to detect using standard GPR procedures. However, hairline faults containing water produce distinct and detectable GPR responses. In addition, the clay layer was successfully identified and its thickness calculated to a satisfactory accuracy.
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Hallak, Neilson John Peter. "Numerical and experimental dynamic analyses of the Vega Pedestrian bridge including seasonal effects." Thesis, KTH, Bro- och stålbyggnad, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255536.
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As timber structures become increasingly relevant and sought after – since they enable improvements in building time while reducing a structure’s life cycle impacts – streamlining their design can have meaningful economic and environmental implications. For timber footbridges, its design is frequently governed by serviceability criteria linked to excessive vibrations. To address this in design, it is necessary to correctly characterize the structure’s dynamic properties and understand what the leading parameters in its behaviour are. This thesis studied an existing timber arch footbridge, aiming to evaluate its dynamic behaviour both with experimental measurements and with theoretical models. The influence of temperature change over different seasons was considered, particularly around its effect on the asphalt layer – whose stiffness is highly correlated to temperature. The experimental results showed high correlation between temperature and natural frequencies: a variation of +21°C reduced the natural frequency for the 1st transverse mode of the deck by as much as 30.6% while the 1st vertical mode was reduced by 17.7% (variation of 0.029Hz/°C). The damping ratio was also measured, though a definitive correlation between its value and temperature was not identified. This change in behaviour cannot be explained by the influence of the asphalt layer alone however, as there is a high degree of uncertainty around many other components of the bridge and their interactions, such as the connections. Thus, to fully characterize the influence of each component with changing temperature, further experimental tests would have to be performed, or simpler structures with fewer connections should be considered. In designing a new structure, considering the asphalt layer as an added mass is a straightforward way to treat this material at the most critical condition (i.e. no contribution to stiffness). This strategy lead to sufficiently similar results between the computational model and the experimental results at warm temperatures. The asphalt stiffness could perhaps be considered for the 1st transverse mode of the deck, since it is in this mode that the asphalt layer plays its largest contribution.
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Kůrka, Jan. "Aplikace dlouhodobého sledování stavebního stavu pro účely hodnocení stávajících zděných železničních obloukových mostů." Doctoral thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-234299.
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Thesis rises from an actual needs to make standard of practice for assessment an existing arch railway masonry bridges on the basis of condition long term monitoring. Bridge assessment is a part of any inspection, especially in case of doubts arising during inspections due to heavy defects, increase of axle load or increase of train frequency, which may influence the structural safety, traffic safety or durability of a bridge. There are possibilities for utilization of monitoring results for assessment in case of investigation data absece. An important option is assessment based on satisfactory past performance by ČSN ISO 13822, chapter 8.
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Bisono, Francisco. "Cultivating a Landscape; A Bridge." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52887.
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a bridge bridges. we build bridges so that we may overcome a perceived break in the continuity of our movement and wonder. the bridge intercedes in order to make a way towards something; beyond a limit, river, border, or mountain. it physically connects that which is perceived as separated.
what is special about a bridge are the many relationships that are illuminated and created by the finished work. towards this end, the architect manipulates the bridge's form and space to render the prevailing relationships of a bridge and its landscape. he works to cultivate the landscape in order to unite the disparate entities present, just as the bridge unites one place with another. through precise and thoughtful compositions, he frames views to capture the beauty of the form he makes, the water it crosses, the earth it springs from and the sky it marvels at. the architect gives us eyes to see the landscape as it ought to be seen.Master of Architecture
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Houšť, Vladimír. "Tenkostěnné přesypané konstrukce." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-234547.
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The thesis is devoted to analysing of flexible buried arch structures. Modelling of the flexible concrete arch is carried out via a nonlinear finite element model that accounts for soil constitutive relations, soil-structure interactions, sequential construction stages and soil compaction. Advanced FE-model was verified by measurement obtained by full-scale field testing of two buried arches. Mathematical optimization methods of genetic algorithms and Levenberg-Marquardt method are applied to already calibrated complex computational models in order to reduce bending and associated flexural stresses in the concrete section of buried arch. Centre line of the arch is parameterized by cubic Bezier curve to reach interpolation of thrust line. Optimization technique is applied with extensive parametrical study which shows the optimal shapes for buried arches of various span/rise ratios, backfill depths and foundation soil types. For practical application are given coordinates of Bézier curve control polygons of particular resulting shape. Subsequently is applied optimization method for a theoretical reduction of tensile stresses obtained by shape optimization of previously verified numerical model of buried arch. Comparisons of earth pressure, bending moment axial force and deflection of flexible structure during sequential construction of different span/raise ratios of buried arches are presented. The behaviour of flexible buried arch with effect of local traffic load model LM1 has been analysed via 3D finite elements model with respect to different depth of backfill above crown.
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Minawi, Ailanto Daniel. "Design of a Long-Span Arch Truss Steel Bridge." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4289/.
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