scholarly journals A New Railway Bridge on Gornalunga River: a Flood Modeling Study.

10.29007/xbjx ◽  
2018 ◽  
Author(s):  
Martina Carlino ◽  
Silvia Di Francesco
Keyword(s):  
Coupled Model ◽  
Railway Bridge ◽  
Surrounding Area ◽  
Flood Modeling ◽  
Railway Line ◽  
Inundation Depth ◽  
Bridge Crossing ◽  
Actual Configuration ◽  
Configuration Simulation ◽  
Modeling Study

In the present work, a 1D-2D-coupled model was used to perform hydraulic analysis of Gornalunga River (Sicily), in order to estimate and analyze the flood risk in correspondence of a crossing bridge. In the frame of the project “Speed up of the railway line Catania-Syracuse”, an existing bridge, crossing Gornalunga River, has to be enlarged and a configuration that mitigates the hydraulic risk on the surrounding area has to be found. At this aim, two different future configurations were considered and a flood modeling study in proximity of the railway crossing in existing and future configurations was conducted using MIKE FLOOD. Depths of flowing water through the bridge, as well as the maximum flood extent and maximum inundation depth have been evaluated for each scenario in order to identify the configuration that minimizes the hydraulic risk for the surrounding area. Finally, the effectiveness of this last solution is analyzed and discussed by comparison with the actual configuration. Simulation results demonstrate that in proximity of the railway bridge water level, as well the hazard risk of the surrounding area decrease passing from the actual configuration to the future one.

Diagnosis of Myslinka Stone Railway Bridge

2016 ◽  
Vol 714 ◽  
pp. 186-191
Author(s):  
Tomáš Bittner ◽  
Milan Hrabánek ◽  
Šárka Nenadálova ◽  
Jiří Kolísko
Keyword(s):  
Visual Observation ◽  
Point Of View ◽  
Water Soluble ◽  
Frame Structure ◽  
Railway Bridge ◽  
Reinforced Concrete Frame ◽  
The Road ◽  
Concrete Frame ◽  
Railway Line ◽  
Second Category

Within the solution of the research project GAČR P105/12/G059 a detailed diagnosis of the stone railway bridge on the railway line Plzeň - Tachov was performed. The bridge is created by two parallel vaulted tubes made from sandstone where a frequented road of second category goes through under one of them and Myslinsky brook flows under the second. The bridge was built approximately in 1978 and in 2006 a reinforced concrete frame structure was built to the bridge portal. Length of both tubes is about 45.5 m, width about 5.7 m, height of the tube above the road is about 6.0 m and above the brook 7.8 m. The arch is made as an annular vault. On the basis of the diagnostic works the structure is evaluated from the point of view of moisture, amount of water soluble salts, strengths of sandstone and there is also a visual observation of a condition of the structure itself performed. In the end there recommendations for a consequent procedure in case of the revitalization are stated.

scholarly journals Seismic Assessment Of Multi-Span Steel Railway Bridge In Turkey Base On The Nonlinear Time History Analyses

2017 ◽  
Author(s):  
Mehmet F. Yilmaz ◽  
Barlas Ö. Çağlayan
Keyword(s):  
Fragility Curves ◽  
Time History ◽  
Field Measurements ◽  
Response Analysis ◽  
Northridge Earthquake ◽  
Railway Bridge ◽  
Railway Line ◽  
Damage Data ◽  
Steel Railway Bridge ◽  
Nonlinear Time History

Abstract. It has been seen that bridges are vulnerable to earthquakes by the research studies after important earthquakes like the San Fernando earthquake (1971 USA), the Northridge earthquake (1994 USA), Great Hanshin earthquake (1995 Japan), and Chi-Chi earthquake (1999 Taiwan). These studies show that to do the seismic risk assessments for bridges, fragility curves are useful tools. There are the most used two ways to generate the fragility curves; empirically or analytically. If the damage reports from past earthquakes are available then empirical fragility curves may be developed but otherwise seismic response analysis of structures may be used to develop analytical fragility curves. In Turkey, earthquake damage data are very limited so to develop the fragility curves for the Alasehir bridge, the analytical method is used in this study. The bridge that is studied on is lying on the Manisa-Afyon railway line that is very important for both transportation and freightage. As the most of the country land covers the seismically active zones it is a necessity to find out the vulnerability of the Alasehir bridge. The Alasehir bridge is consists of six 30 m length truss system span with a total span length of 189.43 m supported by 2 abutments and 5 truss piers with height of 12.5 m, 19 m, 26 m, 33 m and 40 m. Sap2000 is used for computer model of the Alaşehir bridge and the model is refined by using field measurements. Then selected 60 different real earthquake data are used for the analysis by using the refined model. Both material nonlinearity and Δ-δ are considered during the analysis. With this study, seismic behavior of Alasehir steel railway bridge is determined. Truss piers reaction and displacements are used to determine the seismic performance of the Alasehir bridge. Different IMs are compared in terms of efficiency, practicality, and sufficiency. Component and system fragility curve are derived for most proper IMs.

scholarly journals Model studies of flow parameters in the area of bridge supports

2021 ◽  
Vol 244 ◽  
pp. 05014
Author(s):  
Gennady Gladkov ◽  
Konstantin Morgunov ◽  
Yuri Ivanovsky
Keyword(s):  
River Flow ◽  
Flow Characteristics ◽  
Railway Bridge ◽  
Model Studies ◽  
Flow Parameters ◽  
Bridge Structures ◽  
Neva River ◽  
Residual Flows ◽  
Bridge Crossing ◽  
Maximum Minimum

The results of laboratory modeling of the influence of the bridge crossing supports erected during the construction of the highway near the existing railway bridge on the flow characteristics in the channel of the Neva River are presented. Modeling was carried out for two options for the location of the new bridge supports relative to the existing bridge structures. The limits of changes in the characteristics of the river flow are taken into account - the maximum, minimum and residual flows and benchmarks of the water level in the channel. Studies have shown that the construction of the designed bridge supports in the channel does not cause significant changes in the flow structure. There is a redistribution of the flow rate in the sections of the existing and designed bridges. The average velocities in the navigable span of the existing bridge are somewhat reduced when new supports are built. The velocity diagram is aligned along the width of the central and side spans, and a vortex wake is more clearly formed in the area behind the supports.

scholarly journals What controls biological production in coastal upwelling systems? Insights from a comparative modeling study

2011 ◽  
Vol 8 (10) ◽  
pp. 2961-2976 ◽  
Author(s):  
Z. Lachkar ◽  
N. Gruber
Keyword(s):  
Coastal Upwelling ◽  
Net Primary Production ◽  
Current System ◽  
Nutrient Recycling ◽  
Coupled Model ◽  
Comparative Modeling ◽  
Nutrient Concentrations ◽  
Residence Times ◽  
California Current System ◽  
Modeling Study

Abstract. The magnitude of net primary production (NPP) in Eastern Boundary Upwelling Systems (EBUS) is traditionally viewed as directly reflecting the wind-driven upwelling intensity. Yet, different EBUS show different sensitivities of NPP to upwelling-favorable winds (Carr and Kearns, 2003). Here, using a comparative modeling study of the California Current System (California CS) and Canary Current System (Canary CS), we show how physical and environmental factors, such as light, temperature and cross-shore circulation modulate the response of NPP to upwelling strength. To this end, we made a series of eddy-resolving simulations of the two upwelling systems using the Regional Oceanic Modeling System (ROMS), coupled to a nitrogen-based Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD) ecosystem model. Using identical ecological/biogeochemical parameters, our coupled model simulates a level of NPP in the California CS that is 50 % smaller than that in the Canary CS, in agreement with observationally based estimates. We find this much lower NPP in the California CS despite phytoplankton in this system having nearly 20 % higher nutrient concentrations available to fuel their growth. This conundrum can be explained by: (1) phytoplankton having a faster nutrient-replete growth in the Canary CS relative to the California CS; a consequence of more favorable light and temperature conditions in the Canary CS, and (2) the longer nearshore water residence times in the Canary CS, which permit a larger buildup of biomass in the upwelling zone, thereby enhancing NPP. The longer residence times in the Canary CS appear to be a result of the wider continental shelves and the lower mesoscale activity characterizing this upwelling system. This results in a weaker offshore export of nutrients and organic matter, thereby increasing local nutrient recycling and reducing the spatial decoupling between new and export production in the Canary CS. Our results suggest that climate change-induced perturbations such as upwelling favorable wind intensification might lead to contrasting biological responses in the California CS and the Canary CS, with major implications for the biogeochemical cycles and fisheries in these two ecosystems.

Maintenance repair by welding of badly-corroded railway bridge

2018 ◽  
Author(s):  
Janusz Hołowaty
Keyword(s):  
Chemical Composition ◽  
Mild Steel ◽  
Structural Steel ◽  
Corrosion Damage ◽  
Tensile Tests ◽  
Railway Bridge ◽  
Railway Line ◽  
Steel Members ◽  
Passenger Trains ◽  
Bridge Retrofitting

Remedial repairs were carried out on a railway bridge with severe corrosion damage to its steelwork as part of a project to open the passage of freight trains to a railway line in the Upper Silesia region in southern Poland. The bridge was constructed in 1907, using rimmed mild steel for the riveted plate girder superstructures . While the bridge retrofitting plan was being drawn up, the chemical composition of its structural steel members was assessed, and the ste el'' s weldability was confirmed via tensile tests and carbon equivalents. The existing steelwork was strengthened by restoring section losses in the main girders and end cross beams. The stnuctural integrity of the badly-corroded steelwork was recovered, allowing the return of both freight and passenger trains to the railway line.

Influencing Factors of Laws of Bending Force on Railway Bridge

2014 ◽  
Vol 926-930 ◽  
pp. 584-588
Author(s):  
Bao Ru Guo ◽  
Dun Jin Cai ◽  
Ping Wang ◽  
Yi Wen Deng
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Calculation Model ◽  
Railway Bridge ◽  
The Finite Element Method ◽  
Load Range ◽  
Simply Supported ◽  
Railway Line ◽  
Bending Force ◽  
Girder Bridge

Based on the finite element method and the theory of interaction between beam and rail, for girder bridge and the simply supported girder bridge which are common rail continuous bridge as an example, this establishes on railway line - bridge - bridge pier integration calculation model and analyzes the influence of the type of load and load range on the bending force law.

scholarly journals METEOTSUNAMI RISK AND THE USE OF DYNAMIC MOORING ANALYSIS AND SHORETENSION TO MITIGATE RISK IN FREMANTLE PORT

2020 ◽  
pp. 27
Author(s):  
Rohan Hudson ◽  
Justin Cross
Keyword(s):  
Sea Level ◽  
Gravity Waves ◽  
Economic Loss ◽  
Technical Solution ◽  
Railway Bridge ◽  
Loss Of Life ◽  
Railway Line ◽  
Wind Gusts ◽  
Atmospheric Gravity ◽  
Significant Economic Loss

Meteotsunamis are generated by meteorological events, particularly moving pressure disturbances due to squalls, thunderstorms, frontal passages and atmospheric gravity waves. Relatively small initial sea-level perturbations, of the order of a few centimetres, can increase significantly through multi-resonant phenomena to create tsunami like destructive events resulting in injury, loss of life, damage to infrastructure and significant economic loss. On the 17th August 2014, severe metocean conditions (including 27.8 m/s wind gusts and a meteotsunami) resulted in the vessels Grand Pioneer and AAL Fremantle breaking loose from their mooring at Berth 11 and 12 in Fremantle Port. One of the vessels collided with a railway bridge closing the commuter railway line for two weeks. Royal HaskoningDHV was commissioned by Fremantle Ports to undertake a hydrodynamic investigation and a dynamic mooring analysis (DMA) to determine the cause of the event and provide a technical solution to provide safe moorings in the port.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/idTLjfeajiM

scholarly journals Seismic assessment of a multi-span steel railway bridge in Turkey based on nonlinear time history

2018 ◽  
Vol 18 (1) ◽  
pp. 231-240 ◽  
Author(s):  
Mehmet F. Yılmaz ◽  
Barlas Ö. Çağlayan
Keyword(s):  
Fragility Curves ◽  
Time History ◽  
Field Measurements ◽  
Response Analysis ◽  
Railway Bridge ◽  
Intensity Measures ◽  
Railway Line ◽  
Damage Data ◽  
Steel Railway Bridge ◽  
Nonlinear Time History

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.

Evaluation of the Remaining Lifetime of the Piers of the Railway Bridge Crossing the Little Belt, Denmark

2013 ◽  
Vol 99 (13) ◽  
pp. 408-409
Author(s):  
Ole Andersen ◽  
Henrik Moerup ◽  
Knud Christensen
Keyword(s):  
Railway Bridge ◽  
Bridge Crossing
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