Innovative Suspended Superstructure for the Retrofitting of a Steel Truss Railway Bridge

2018 ◽  
Vol 763 ◽  
pp. 1121-1128
Author(s):  
Marco Mezzi ◽  
Gianluca Nestovito ◽  
Paolo Petrella ◽  
Vincenzo Cefaliello
Keyword(s):  
National Standard ◽  
Railway Network ◽  
Fluvial Erosion ◽  
Railway Line ◽  
Load Models ◽  
Emilia Earthquake ◽  
Structural Capacity ◽  
Railway System ◽  
2012 Emilia Earthquake ◽  
Suspended Bridge

The bridge in Poggio Renatico crossing the Reno river on the railway line between Bologna and Ferrara, consists of steel decks supported by masonry abutments and piers, while foundations and pier caps are made of reinforced concrete. After the 2012 Emilia Earthquake and accounting for the fluvial erosion below the piers foundations, a structural assessment of the bridge was carried out in accordance with to the current Italian rules. Although a sufficient structure capacity against the actual transit loads resulted, the bridge showed some inadequacies with respect to the load models provided by both the national standard for constructions and the guidelines of the Italian railway network company. The retrofitting project consists of an improvement of the structural capacity of all the elements: girders, piers and abutments. An innovative retrofitting solution provides for the strengthening of the existing decks through a suspension system of cables anchored to steel towers standing on both abutments and piers and creating a kind of suspended bridge. The retrofitting is compatible with the normal scheduled interruptions of the rail traffic thereby reducing the maintenance costs of the railway system. The structural solution represents a model easily replicable to solve analogous situations along the railway network.

Comparison on General Track Spectrum for Chinese Main Railway Lines and Track Spectrum of American Railway Lines

2011 ◽  
Vol 250-253 ◽  
pp. 3822-3826 ◽  
Author(s):  
Xian Mai Chen ◽  
Xia Xin Tao ◽  
Gao Hang Cui ◽  
Fu Tong Wang
Keyword(s):  
Dynamic Performance ◽  
Dynamic Responses ◽  
Wave Band ◽  
Wheel Load ◽  
Railway Line ◽  
Acceleration Rate ◽  
Time Histories ◽  
Railway System ◽  
Dynamic Performances ◽  
Track Irregularity

The general track spectrum of Chinese main railway lines (ChinaRLS) and the track spectrum of American railway lines (AmericaRLS) are compared in terms of character of frequency domain, statistical property of time domain samples and dynamic performance. That the wavelength range of the ChinaRLS, which is characterized by the three levels according to the class of railway line, is less than AmericaRLS at common wave band of 1~50m is calculated. Simultaneously, the mean square values of two kinds of track spectra are provided at the detrimental wave bands of 5~10m, 10~20m, and so on. The time-histories of ChinaRLS and AmericaRLS are simulated according to the trigonometric method, and the digital statistical nature of simulated time samples is analyzed. With inputting the two kinds of time-histories into the vehicle-railway system, the comparative analysis of the two kinds of dynamic performances for ChinaRLS and AmericaRLS is done in terms of car body acceleration, rate of wheel load reduction, wheel/rail force, and the dynamic responses of track structure. The result shows that ChinaRLS can characterize the feature of the Chinese track irregularity better than AmericaRLS, the track irregularity with the ChinaRLS of 200km/h is superior to the AmericaRLS, and the track irregularity with the ChinaRLS of 160km/h corresponds to with the sixth of AmericaRLS.

scholarly journals Preliminary results of ground-motion characteristics

2012 ◽  
Vol 55 (4) ◽  
Author(s):  
Francesca Bozzoni ◽  
Carlo Giovanni Lai ◽  
Laura Scandella
Keyword(s):  
Ground Motion ◽  
Site Response ◽  
Response Spectrum ◽  
Field Tests ◽  
Response Spectra ◽  
Ground Acceleration ◽  
Preliminary Results ◽  
Emilia Earthquake ◽  
Particle Orbit ◽  
2012 Emilia Earthquake

The preliminary results are presented herein for the engineering applications of the characteristics of the ground motion induced by the May 20, 2012, Emilia earthquake. Shake maps are computed to provide estimates of the spatial distribution of the induced ground motion. The signals recorded at the Mirandola (MRN) station, the closest to the epicenter, have been processed to obtain acceleration, velocity and displacement response spectra. Ground-motion parameters from the MRN recordings are compared with the corresponding estimates from recent ground-motion prediction equations, and with the spectra prescribed by the current Italian Building Code for different return periods. The records from the MRN station are used to plot the particle orbit (hodogram) described by the waveform. The availability of results from geotechnical field tests that were performed at a few sites in the Municipality of Mirandola prior to this earthquake of May 2012 has allowed preliminary assessment of the ground response. The amplification effects at Mirandola are estimated using fully stochastic site-response analyses. The seismic input comprises seven actual records that are compatible with the Italian code-based spectrum that refers to a 475-year return period. The computed acceleration response spectrum and the associated dispersion are compared to the spectra calculated from the recordings of the MRN station. Good agreement is obtained for periods up to 1 s, especially for the peak ground acceleration. For the other periods, the spectral acceleration of the MRN recordings exceeds that of the computed spectra.<br />

scholarly journals Method for Determining the Valid Travel Route of Railways Based on Generalised Cost under the Syncretic Railway Network

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Zhiqiang Tian ◽  
Guofeng Sun ◽  
Dingjun Chen ◽  
Zhicheng Qiu ◽  
Yawen Ma
Keyword(s):  
High Speed ◽  
Search Algorithm ◽  
Cost Calculation ◽  
Railway Network ◽  
Line Planning ◽  
Integrated Network ◽  
Railway Line ◽  
Passenger Travel ◽  
Normal Speed ◽  
Generalised Cost

Travel route options for passengers can provide data support for railway line planning, passenger flow organisation, and train operation establishment. A critical review of the literature indicates that previous studies mainly focused on choices offered by a single railway network path without much consideration of China’s normal-speed and high-speed integrated railway network and the effect of train timetable on passengers’ travel choice. In this study, a method based on generalised cost is proposed to discover the valid routes of passenger travel in the integrated network of China’s normal-speed and high-speed railways. After quantifying the effects of train fare, travel time, transfer, travel convenience, comfort, and other factors on the generalised expenses of passengers, this study presents a generalised cost determination method when individuals select an option from different seats of different trains of specific railway transport products. Theoretically, the valid routes considering the train schedule is defined, and a valid route search algorithm is designed using the deep traversal idea in a new valid route searching network. Considering the Lanzhou-Beijing passenger travel routes as an example, this study verifies the practicability of the generalised cost calculation method, as well as that of the valid routes search method.

scholarly journals The Distribution Pattern of the Railway Network in China at the County Level

2019 ◽  
Vol 8 (8) ◽  
pp. 336
Author(s):  
Minmin Li ◽  
Renzhong Guo ◽  
You Li ◽  
Biao He ◽  
Yong Fan
Keyword(s):  
Distribution Pattern ◽  
Geographical Information ◽  
Eastern Region ◽  
Gis Technology ◽  
Railway Network ◽  
Macro Scale ◽  
Social And Economic Development ◽  
Distribution Index ◽  
Railway System ◽  
Network Proximity

Evaluation of the railway network distribution and its impacts on social and economic development has great significance for building an efficient and comprehensive railway system. To address the lack of evaluation indicators to assess the railway network distribution pattern at the macro scale, this study selects eight indicators—railway network density, railway network proximity, the shortest travel time, train frequency, population, Gross Domestic Product (GDP), the gross industrial value above designated size, and fixed asset investment—as the basis of an integrated railway network distribution index which is used to characterize China’s railway network distribution using geographical information system (GIS) technology. The research shows that, in 2015, the railway network distribution was low in almost half of China’s counties and that there were obvious differences in distribution between counties in the east and west. In addition, multiple dense areas of railway network distribution were identified. The results suggest that it might be advisable to strengthen the connections between large and small cities in the eastern region and that the major urban agglomerations in the midwest could focus on strengthening the construction of railway facilities to increase the urban vitality of the western region. This study can be used to guide the optimization of railway network structures and provide a macro decision-making reference for the planning and evaluation of major railway projects in China.

scholarly journals A discussion on technologies for improving the operational speed of high-speed railway networks

2019 ◽  
Vol 1 (1) ◽  
pp. 22-36 ◽  
Author(s):  
Chun-fang Lu
Keyword(s):  
High Speed ◽  
Rapid Development ◽  
Practical Significance ◽  
Railway Network ◽  
High Speed Railway ◽  
Development Status ◽  
Improvement Plan ◽  
Railway System ◽  
Traction Power Supply ◽  
Traction Power

Abstract: China’s high-speed railway network has already achieved speeds of 350 km/h; however, this could be further increased to 400 km/h. After considering the development status and technical level of the high-speed railway system in China, this study indicates that there are four key technologies involved in improving its operational speed: the track, the electrical moving unit, the control system and the traction power supply. Through an experimental analysis, an evaluation index for the high-speed railway is then constructed based on four aspects: safety, comfort, intelligence and environmental protection. Using this system, the rationality of the high-speed railway speed-improvement plan can be scientifically evaluated. The results are of practical significance to the Chinese railway administration, as they can be used to formulate specific plans to increase rail speeds, and therefore promote the rapid development of the high-speed railway network in China.

scholarly journals Operational criteria in the justification of electrification of railway lines

2018 ◽  
Vol 180 ◽  
pp. 06005
Author(s):  
Andrzej Massel
Keyword(s):  
Rolling Stock ◽  
The Political ◽  
Economic Factors ◽  
Single Track ◽  
Railway Network ◽  
Railway Line ◽  
Passenger Traffic ◽  
Post War ◽  
Operational Criteria ◽  
Double Track

The process of electrification of the Polish railways took place from 1936 till early 1990s. Despite the political constraints of the post-war times, the decisions on electrification of particular sections of the railway network were usually based on economic factors. In 1970s and 1980s so called electrification thresholds were used to justify the need for electrification of railway line in question. They took into the number of tracks (single-track lines, double-track lines), terrain conditions (flat terrain, upland terrain) and the traffic structure (the share of passenger traffic) into account. In the framework of National Railway Program till 2023 (KPK) the realization of electrification projects have been undertaken again. The present paper deals with importance of the operational criteria in the decision-making concerning justification of electrification of railway lines. These criteria include the shortening of the journey times on particular sections, shortening of stops on the stations with the change of the type of traction, the savings of train operating companies resulting from the traction unification (change of demand for rolling stock and for workshops for its servicing), improvement of reliability and punctuality of services.

The Vulnerability Assessment Method of Railway Network

2010 ◽  
Author(s):  
Wei Wang ◽  
Jun Liu ◽  
Li Haiying ◽  
Xi Jiang
Keyword(s):  
Transport System ◽  
Network Topology ◽  
Dynamic Process ◽  
Vulnerability Assessment ◽  
System Performance ◽  
Assessment Method ◽  
Level Of Service ◽  
Railway Network ◽  
Railway System ◽  
Integral Element

Vulnerability in the Railway system is, studied not only from the perspective of network topology characteristic but also as the problem of the level of service relative to structure, nature damage and traffic attribute. Also, emphasis is put on the function of the system rather than the physical network itself, although some of non-serviceability in the railway network is indeed caused by physical failures. The Vulnerability of railway network is thus a decisive factor not only in terms of connectivity, and serviceability, but also in terms of the transport system performance under dynamic process-traffic which should be acknowledged as an integral element within vulnerability assessment. The paper aims at investigating the most typical factors that affect the vulnerability. The vulnerability analysis must consider each factor separately, and, at the same time, as a whole. A method to measure the vulnerability is proposed. Furthermore, this assessment method is used to analyze the Chinese Railway Network (CRN).

DESIGN AND PROJECT PLANNING OF THE RENOVATION OF A RAILWAY LINE

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Amelie Outtier ◽  
Bart De Pauw ◽  
Hans De Backer
Keyword(s):  
Project Planning ◽  
Small Scale ◽  
Night Time ◽  
Railway Network ◽  
Railway Line ◽  
Pretensioned Concrete

The railway line L50A is one of the most important lines in Belgium, connecting the capital Brussels with Ghent. The line originally consisted out of two tracks. Because this formed a constricting bottleneck for the entire railway network in Belgium, the existing capacity was expanded. Between 2008 and 2015 a third and fourth track was constructed, one on each side of the original 2 tracks. Now that the expansion works have ended, the 2 original tracks have to be refurbished. The necessary works include: renewal of ballast and rails, changing all wooden sleepers by pretensioned concrete ones, strengthening of the subgrade and renewal and improvement of the waterproofing layers at the bridges and viaducts. This article focuses on the first 10 kilometers of the trajectory, including 10 locations where the waterproofing has to be renewed. At each location, the existing ballast, sleepers and tracks have to be removed for the middle two tracks, so a new polyethylene-waterproofing layer can be installed. Afterwards the tracks have to be restored. All of this has to be performed while the 2 outer tracks remain in operation and without disturbing the electrification cables above the tracks. Because of this, the project will necessitate a combination of creative planning, use of modified and small-scale equipment and a judicious use of night-time labor. All of these items will be discussed in the article.

scholarly journals Modeling earthquake effects on groundwater levels: evidences from the 2012 Emilia earthquake (Italy)

Geofluids ◽  
2015 ◽  
Vol 16 (3) ◽  
pp. 452-463 ◽  
Author(s):  
M. Nespoli ◽  
M. Todesco ◽  
E. Serpelloni ◽  
M. E. Belardinelli ◽  
M. Bonafede ◽  
...  
Keyword(s):  
Groundwater Levels ◽  
Emilia Earthquake ◽  
2012 Emilia Earthquake ◽  
Earthquake Effects
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