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.

The aim of this thesis is to study and gain more insight about the static behaviour of the three hinged single diagonal timber arch bridge in different situations. The bridge was tested for static analyses for both Ultimate Limit State and Serviceability Limit State, to investigate its behaviour and if it is possible to be built at the selected location. Furthermore, the dimensions of the elements are to be determined. Pre-studies on similar bridges have been done and their problems have been taken into account when analysing the behaviour of this bridge. Thereafter, two different designs have been constructed. The finite element software RFEM has been used in this project to be able to analyse the behaviour of the two different models. The in-plane buckling of the arch is the most critical part of the bridge and the bridge should therefore be designed regarding that. Additionally, different alternatives were suggested to reduce the deformation of the deck in the models. Finally, an optimized model is reached which consists of longitudinal beams and has an arch with a wide cross section.

Due to their structural efficiency and architectural elegance, concrete arches have long been used in bridge applications. However, the construction of concrete arches requires significant temporary supporting structures, which prevent their widespread use in modern bridges. A relatively new form of arch bridges is the network arch, in which a dense arrangement of inclined hangers is used. Network arches are subjected to considerably smaller bending moments and deflections than traditional arches and are therefore suitable for modern, accelerated construction methods in which the arches are fabricated off-site and then transported to the bridge location. However, service-level stresses, which play a critical role in the performance of the structure, are relatively unknown for concrete network arches and have not been sufficiently investigated in the previous research on concrete arches. The primary objective of this dissertation is to improve the understanding of short-term and time-dependent stresses in concrete arches, and more specifically, concrete network arches. The research presented herein includes extensive field monitoring of the West 7th Street Bridge in Fort Worth, Texas, which is the first precast network arch bridge and probably the first concrete network arch bridge in the world. The bridge consists of twelve identically designed concrete network arches that were precast and post-tensioned before they were transported to the bridge site and erected. A series of vibrating wire gages were embedded in the arches and were monitored throughout the construction and for a few months after the bridge was opened to traffic. The obtained data were processed, and structural response parameters were evaluated to support the safe construction of the innovative arches, identify their short-term and time-dependent structural behavior, and verify the modeling assumptions. The variability of stresses among the arches was also used to assess the reliability of stress calculations. The results of this study provide valuable insight into the elastic, thermal, and time-dependent behavior of concrete arches in general and concrete network arches in particular. The knowledge gained in this investigation also has broader applications towards understanding the behavior of indeterminate prestressed concrete structures that are subjected to variable boundary conditions and thermal and time-dependent effects.

Baigiamajame magistro darbe atliekama plieninių neskėtrių arkinių tiltų pastovumo plokštumoje analizė. Pirmajame skyriuje apžvelgiami pavienių gniuždomųjų strypų, arkų ir arkinių tiltų pastovumo tikrinimo metodai, pateikiamos projektavimo normos ir jų taikymo sritys. Antrajame skyriuje pateikiamas analiziniais ir skaitiniais metodais apskaičiuotų pavienių strypų ir arkų pastovumo parametrų palyginimas. Konstrukcijų pastovumo analizei atlikti naudojamas programinis paketas „Sofistik“. Skaičiuojant pastovumo parametrus vertinama arkos geometrinė apybrėža, apkrovimo pobūdis, lenkiamasis standis, aukščio ir tarpatramio santykis. Nustatomi racionalūs arkos geometriniai parametrai. Trečiajame skyriuje nagrinėjami dvimačiai neskėtrių arkinių tiltų modeliai. Vertinama tinklelio pakabų skaičiaus ir išdėstymo įtaka pastovumui. Palyginami neskėtrių arkinių tiltų stabilumo analizės rezultatai. Pateikiamos išvados ir rekomendacijos. Darbą sudaro: įvadas, trys skyriai, bendrosios išvados ir rekomendacijos, literatūros sąrašas, priedai. Darbo apimtis – 96 puslapiai, 66 paveikslai, 26 lentelės, 32 bibliografiniai šaltiniai. / The master thesis is carried out for in plane stability analysis of tied steel arch bridges. In first chapter overview of the individual compression bars, arches and arch bridges stability testing methods is presented. The first chapter also provides design standards and their application areas. The whole structural stability analysis was performed using “Sofistik” finite element software. Using software two dimensional models of arches and arch bridges were made. Second chapter concludes comparison of analytical and numerical stability analysis of single arches. Stability parameter and effective length factor was calculated according to arch geometric outlines, load type, bending stiffness, height and span ratio. The third chapter consists of stability analysis of two dimensional arch bridge models. Different suspension cable grids were used in order to compare and evaluate stability analysis results. Comparison of stability factors of various versions of arch bridges was made. Conclusions and recommendations are presented in the final chapter. The work contains: introduction, three chapters, conclusions and recommendations, references and appendices. The whole work consists of – 96 pages, 66 figures, 26 tables, 32 references.

No description available.

In dieser Arbeit wurde eine 110 m weit spannende Netzwerkbogenbrücke für eingleisigen Eisenbahnverkehr unter Lastmodell (LM) 71, auf Basis der Forschungsergebnisse Teichs entworfen und nach den Vorgaben der DIN EN 1990, 1991 und 1993 bemessen. Im Rahmen des Entwurfs wurde eine Variantenuntersuchung durchgeführt. Ferner wurde ein Montagekonzept erstellt.

Content of this master's thesis is reconstruction of road brigre and determination of its load capacity before and after reconstruction.

As America's infrastructure ages, many of the nation'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

The subject of this diploma thesis is the structural design of a railway bridge over river Dyje based on materials given by my supervisor. The tied arch bridge with prestressed concrete girder is chosen for the structural check. The structural assesment is focused on prestressed concrete girder and basic calculations are made to check steel arch and hangers as well. Eigenvalue analysis provides dynamic properties of this structure. Appendices contain Structural design report, drawings including Construction stages scheme and visualization. For structural analysis Midas Civil software was used. Other used softwares for visualization, and outputs etc are: Lumion12, IdeaStatica, Microsoft excel and Autocad

A constant research of more ecological and efficient structures has enabled bridges to be more innovative through the years. Nowadays, as the need is greater than ever, a new kind of bridge is expanding in the entire world: the network arch bridges. The concept was developed by professor and engineer Per Tveit in 1955 and has been improved since then. But it is only for 10 years that many bridges of this sort have been built. The aim of the thesis is to investigate the structural behavior of these bridges and their efficiency comparing to traditional bridges. It is also proving the efficiency of the network arches used for rail traffic. To do so, a single-track railway network arch has been designed according to the Eurocodes. A 2D model has been designed to be optimal and tested under Abaqus for the loads defined in the Eurocodes. Guidelines from the literature and Per Tveit’s work have been used to determine the optimal geometry of the bridge. The steel weight needed for the 75 meters long bridge is assessed from the final design and is the main parameter to compare and evaluate the network arch structural efficiency. These results are compared with Tveit’s statements and with other structures.