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Abstract. Many research studies have shown that bridges are vulnerable to earthquakes,
graphically confirmed by incidents such as the San Fernando (1971 USA),
Northridge (1994 USA), Great Hanshin (1995 Japan), and Chi-Chi (1999 Taiwan)
earthquakes, amongst many others. The studies show that fragility curves are
useful tools for bridge seismic risk assessments, which can be generated
empirically or analytically. Empirical fragility curves can be generated
where damage reports from past earthquakes are available, but otherwise,
analytical fragility curves can be generated from structural seismic response
analysis. Earthquake damage data in Turkey are very limited, hence this study
employed an analytical method to generate fragility curves for the Alasehir
bridge. The Alasehir bridge is part of the Manisa–Uşak–Dumlupınar–Afyon
railway line, which is very important for human and freight transportation,
and since most of the country is seismically active, it is essential to
assess the bridge's vulnerability. The bridge consists of six 30 m truss
spans with a total span 189 m supported by 2 abutments and 5 truss piers,
12.5, 19, 26, 33, and 40 m. Sap2000 software was used to model the Alasehir
bridge, which was refined using field measurements, and the effect of 60 selected
real earthquake data analyzed using the refined model, considering
material and geometry nonlinearity. Thus, the seismic behavior of Alasehir
railway bridge was determined and truss pier reaction and displacements were
used to determine its seismic performance. Different intensity measures were
compared for efficiency, practicality, and sufficiency and their component
and system fragility curves derived.

In the context of bridge management, three main types of maintenance actions can be considered. Maintenance actions can be taken preventively before the predefined limit condition is reached, or as a corrective measure in case those limits have been reached. The third possibility corresponds to the so-called "doing nothing" scenario, in which no action is taken on the bridge. To be able to implement preventive maintenance, it is necessary to know the current condition of the bridge, as well as to be able to predict its performance. On the other hand, it is also important to be able to identify potentially threatening events that might occur in the analysis life period. This paper describes an integrated methodology to help bridge managers in defining an efficient maintenance program, considering the specific case of a railway bridge. The novelty of the methodology is focused on updating an existing methodology proposed by COST TU1406, by extending it to railway bridges and also by including the resilience analysis in case of a sudden event occurrence. The analysis considers a multi-hazard future scenario, in which a flood event occurs while corrosion phenomena were already in place. The results show the feasibility of the proposed methodology as a support for the establishment of an efficient maintenance schedule to prevent bridge severe degradation, as well as to establish recovery plans in case of a sudden event. ; This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), reference no. UIDB/04029/2020; HYPER FCT–Por tuguese Scientific Foundation, research grant no. PD/BD/ 128015/2016, under the Ph.D. program "Innovation in Railway System and Technologies-iRail" of the author João N.D. Fernandes; and European Union's Horizon 2020 re search and innovation programme, grant agreement no. 769255. ,e authors would like to thank the Portuguese company "Infraestruturas de Portugal (IP)" for providing ...

This item is part of the Political & Rights Issues & Social Movements (PRISM) digital collection, a collaborative initiative between Florida Atlantic University and University of Central Florida in the Publication of Archival, Library & Museum Materials (PALMM).

Non-destructive Structural Health Monitoring techniques can be incorporated into bridge integrity management by assessing structural conditions. This paper describes a performance assessment of a steel truss railway bridge in Bratislava using vibration-based techniques as a further part of maintenance in addition to standard visual inspections. To obtain the necessary data, a multipurpose measuring system was used. Various types of data were measured, e.g. accelerations, strains, and displacements. The advantage of the multipurpose measuring system was that the traffic over the bridge was not restricted, even though the bridge carries only a single curved track. Two test campaigns were conducted to assess the performance of the bridge. One campaign was devoted to measuring ambient vibrations in order to perform the operational modal analysis, and the second was carried out to measure strains and displacements during a train passage. The results show a successful system identification of the structure using ambient vibrations; and a finite element model was verified and validated by a comparison of strains and displacements, as well as by modal parameters. According to the results obtained, the structural health of the investigated bridge was satisfactory.

The Merivale Bridge is a double track railway bridge crossing the Brisbane River. It crosses the Milton Reach of the river, slightly to the west of the William Jolly Bridge. Exclusively a railway crossing, it is located between the stations of South Brisbane and Roma Street, linking the northern and southern elements of the Queensland Rail City network. The Merivale Bridge is the only inner-city rail crossing in Brisbane. By 2016 it was expected to be over capacity, leading the Queensland Government to announce the Cross River Rail project. The Merivale Bridge opened on 18 November 1978 by Premier Joh Bjelke-Petersen.At the opening, the then Premier, described the occasion as "the start of the second stage in the history of Queensland Railways". It formed a more direct route into the city for Brisbane's southern system suburban trains than the existing route via Corinda. It also carries the standard gauge line from New South Wales. It was designed by Cameron McNamara Pty Ltd (consulting engineers) and was fabricated and erected by Transfield. The bridge has been recognised with a number of awards. In 1980 it was named the most outstanding engineering project from the Association of Consulting Engineers of Australia.[4] Judges appreciated the combination of aesthetics and functionality. It also won the 1979 Steel Award. (Wikipedia)

[EN] Highway and railway bridges are exposed to cyclic stressing due to traffic loads and, therefore, have to be evaluated concerning fatigue. In most cases the fatigue evaluation is performed according to Eurocode 3 Part 1-9 on nominal stresses. To apply this nominal stress approach a detail catalogue is required classifying all relevant constructional details in terms of fatigue. Unfortunately, the existing detail catalogue of Eurocode 3 Part 1-9 reflects the state of the art of the 1990s and misses constructional details being important for today's bridge design. As an example the derivation of a new detail, the so-called lamellae joint, is presented. Furthermore, for two new types of innovative steel bridges, where Eurocode 3 Part 1-9 does not yet specify rules able to evaluate the characteristics of these bridges, research results are shown. These are the thick-plate trough bridges and truss bridges made of thick-walled circular hollow sections (CHS). The paper starts with an overview on the recent Eurocode developments, addressing more specific the fatigue verification according to EN 1993-1-9 and the statistical analysis of fatigue test data. In the following, information is given on the outcome of some recent research projects striving to extend the application range of Eurocode 3 Part 1-9. The final conclusion, in spite of all differences, show a common tendency. ; The work presented is carried out as part of several joint research projects (P815 [3], P978 [18]) of the Research Association for Steel Application (FOSTA) and (No. 15380 [15], No. 17104 [16]) of the German Committee for Steel Construction (DASt). They were financed over the AiF within the evelopment program for industrial community research and development (IGF) from the Federal Ministry of Economic Affairs and Energy (BMWi) based on a decision of the German Bundestag. ; Kuhlmann, U.; Bove, S.; Breunig, S.; Drebenstedt, K. (2018). Fatigue of steel bridges. En Proceedings of the 12th International Conference on Advances in Steel-Concrete ...

A railway route contains a number of bridge structures along its path. Consequently during operation, these bridges go through different type of load and stresses; as a result the bridges get damaged. The severity of the damage is mainly dependent on the volume of traffic, tonnage of the rolling stock, service year of the bridge, maneuver of users, etc. But in order to determine whether a bridge needs to be maintained or reconstructed, there must be an investigation, either thorough or timely scheduled investigation. Asset management is a strategic and systematic process through which an organization procures, operates, maintains, rehabilitates, and replaces assets to manage their performance, risks, and costs over their lifecycle to provide safe, cost-effective, and reliable service to current and future customers. For an organization to have a proficient bridge asset management, incorporating BMS in the system is very important. BMS is a formal procedure for collecting, processing, and updating data, predicting deterioration, identifying alternative actions and predicting their costs, and identifying optimal preservation policies. For an effective bridge management, computer aided management system is a very valuable choice that would serve the need of the authorized legal entity management personnel those responsible for monitoring of Railway Bridges, and managing bridge maintenance, rehabilitation, and reconstruction. This research study is focused to develop and introduce a computer program that could assist specially bridge asset management decision making. Transportation accesses are critical to the well being of the nation. And one of the biggest factors to influence transportation is railway transport service. It supports everyday social, political and economic activities by linking communities and connecting people with services. Hence, keeping the railway infrastructures in good condition is keeping the railway transport service efficiently. The computer program graphical interface is designed using Visual Basic Programming tool which is user friendly and easy to slot in all necessary information in to the computer. The data encoded in to the software are stored for fast and reliable accessibility using SQL (Server Query Language) Server, which allows all authorized computers on the network to access the information on their desk. The computer program does bridge registration and inventory, inspection data processing, priority ranking, maintenance cost estimation and maintenance plan generation.

A railway route contains a number of bridge structures along its path. Consequently during operation, these bridges go through different type of load and stresses; as a result the bridges get damaged. The severity of the damage is mainly dependent on the volume of traffic, tonnage of the rolling stock, service year of the bridge, maneuver of users, etc. But in order to determine whether a bridge needs to be maintained or reconstructed, there must be an investigation, either thorough or timely scheduled investigation. Asset management is a strategic and systematic process through which an organization procures, operates, maintains, rehabilitates, and replaces assets to manage their performance, risks, and costs over their lifecycle to provide safe, cost-effective, and reliable service to current and future customers. For an organization to have a proficient bridge asset management, incorporating BMS in the system is very important. BMS is a formal procedure for collecting, processing, and updating data, predicting deterioration, identifying alternative actions and predicting their costs, and identifying optimal preservation policies. For an effective bridge management, computer aided management system is a very valuable choice that would serve the need of the authorized legal entity management personnel those responsible for monitoring of Railway Bridges, and managing bridge maintenance, rehabilitation, and reconstruction. This research study is focused to develop and introduce a computer program that could assist specially bridge asset management decision making. Transportation accesses are critical to the well being of the nation. And one of the biggest factors to influence transportation is railway transport service. It supports everyday social, political and economic activities by linking communities and connecting people with services. Hence, keeping the railway infrastructures in good condition is keeping the railway transport service efficiently. The computer program graphical interface is designed using Visual Basic Programming tool which is user friendly and easy to slot in all necessary information in to the computer. The data encoded in to the software are stored for fast and reliable accessibility using SQL (Server Query Language) Server, which allows all authorized computers on the network to access the information on their desk. The computer program does bridge registration and inventory, inspection data processing, priority ranking, maintenance cost estimation and maintenance plan generation.

Development of cooperation within European Union stimulates intensive integration between all components of European transportation system. One of the important fields of integration is railway bridge engineering, a part of railway transportation system. Proposed classification of degradation mechanisms against their effects as bridge structure defects can be a basis for the unified assessment of bridge condition. Presented terminology and classifications elaborated in the European research project "Sustainable Bridges" can be useful in condition assessment by bridge inspectors as well as in knowledge-based computer tools supporting evaluation procedures in the advanced Bridge Management Systems. Identified relationships between degradation processes and defects can be used for optimization of bridge infrastructure maintenance and ...

Due to the substantial role of bridges in transportation network and in accordance with the limited fund for bridge management, remedial strategies have to be prioritized. A conservative bridge assessment will result in unnecessary actions, such as costly bridge strengthening or repairs. On the other hand, negligence and delayed action of bridge maintenance may lead to heavy future costs or degraded assets. The accuracy of decisions developed by any manager or bridge engineer relies on the accuracy of the bridge assessment which emanates from well-established bridge Inventory and Inspection. A high degree of accurate Bridge Database is only maintained if the bridge Inventory and Inspection is carried out using well-established guideline. If bridge Inventory and Inspection tasks are not performed for all bridges without having a well-established guideline, frequent collapse would occur at the same time in many parts of the county and would provoke social and political chaos. As a new government corporate the Ethiopian Railway Corporation needs to start the bridge asset management by inventory and inspecting of its new assets. To perform this, sustainability of well-established bridge Inventory and Inspection guideline should be established. Therefore; the main goal of this research is study preparation of Inventory and Inspection Guideline for Railway Bridges in Ethiopia by adapting the practice in similar sources. In this research Inventory and Inspection Guideline for Ethiopian railway bridges is studied from the experience of different countries, bridges administration authorities ERA, AACRA, manuals and others relevant sources, and a seed for Rail Bridge Management System established.

This paper describes the "Variation Guggenheim 3: Mirador de la palmera" project, situated in Daya Vieja (Alicante-Spain). This structure is inspired by the Guggenheim museum of New York and is designed to protect a land-mark palm-tree from wind loads. This six – trunk palm tree was declared monument by the Valencian government in 2012. The structure that now protect it appears to fly around de palm tree creating a helicoidally skywalk made of steel, while retrofitting the lateral trunks of the tree to protect them from collapse. An 18 m. long straight beam starts on the top of this helix, and stretches towards a lookout point that offers a view of the whole village and its surroundings. The reduction of the visual impact of the structure on the tree was a major aim for the project design. The structural elements are as slender as possible to avoid the visual obstruction of tree. They are painted white, while the walkway steel corrugated plate is painted green in order to highlight its neat shape among the blur created by the apparent mess of bars of the supporting structure. The two main piles of this pedestrian bridge were designed in steel and geometrically resemble trees. A Ground Penetrating Radar analysis was performed to detect the palm root location and to decide the best foundation system. Slender cast in-situ steel-concrete micropiles along with a concrete pile-cap, raised some centimeters above the ground level, were used to reduce the damage to the roots. The projected pile-cap is a slender, continuous, circular ring; which geometry resembles a concrete bench. This structure has been a finalist in the Architecture Awards for the 2010-2014 best construction projects, held by the Diputación de Alicante.

With the suspension of the investment into the V0 railway line, the issue of the railway lines bypassing Budapest came to the front again. As an alternative of building a new railway line, the development of existing ones or the rebuilding of lines that have been in operation in the past should be examined. In this paper, we deal with a previously operated, now discontinued Danube crossing facility, the Solt–Dunaföldvár railway bridge. Although this crossing was of minor importance during its operation, it is worth examining the role it can play should it be rebuilt with parameters required for a TEN-T railway line. According to our graph-theory based calculations, such a bridge cannot only be part of the only reasonable detour if the Southern Railway Bridge in Budapest is disrupted but can also be a facility disencumbering it under normal operational conditions.

As bridges provide crossing at critical points such as waterways, valleys and other type of physical obstacles, they are invaluable assets within a rail network. However, these infrastructures are exposed to several hazards of different natures that compromise their structural safety and ultimately lead to critical events. Accord-ing to literature, there are commonly five levels of assessment of safety with increasing complexity per level. Level 1, consisting on an assessment based on partial coefficients, is the simplest one, whereas level 5 is the most complex involving a combination of non-linear analysis and probabilistic assessment. Within that scope, this paper analyses the structural safety of a pre-stressed reinforced concrete railway bridge located in Portugal, by using a combination of linear elastic and probabilistic analysis procedures. The proposed framework is adaptable and suitable for common safety analysis. The obtained reliability index is compared to threshold values given by different standards which validates that the bridge ensures the safety at ultimate limit state. The reliability levels along time are also determined assuming a reduction in the cross-section area of the steel reinforcement, resulting from corro-sion initiation based on onsite inspection evidences. From the analysis of this scenario over time, it may be concluded that the bridge under study exhibits sufficient load carrying capacity during its planned service life even under the proposed damage. ; The third author would like to thank FCT – Portuguese Scientific Foundation for the research grant PD/BD/128015/2016 under the PhD program "Innovation in Railway System and Technologies- iRail". This work was partly financed by FEDER funds through the Competitivity Factors Operational Programme - COMPETE and by national funds through FCT Foundation for Science and Technology within the scope of the project POCI-01- 0145-FEDER-007633. This project has received funding from the European Union's Horizon 2020 research and innovation ...