Experimental modal analysis of a twin composite filler beam railway bridge for high-speed trains with continuous ballast

Experimental modal analysis is a relatively young part of dynamics, which deals with the vibration modes identification of machines or their parts. Its development has started since the beginning of the eighties, when the computers hardware equipment has improved and the fast Fourier transform (FFT) could be used for the results determination. Nowadays it provides an uncountable set of vibration analysis possibilities starting with conventional contact transducers of acceleration and ending with modern noncontact optical methods. In this contribution we mention the use of high-speed digital image correlation by experimental determination of mode shapes and modal frequencies. The aim of our work is to create a program application called Modan 3D enabling the performing of experimental modal analysis and operational modal analysis. In this paper the experimental modal analysis of a thin steel sample performed with Q-450 Dantec Dynamics is described. In Modan 3D the experiment data were processed and the vibration modes were determined. The reached results were verified by PULSE modulus specialized for mechanical vibration analysis.

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Effect of High-Speed Train-Induced Wind on Trackside UAV Thrust Near Railway Bridge

Applied Sciences ◽

10.3390/app10103495 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3495 ◽

Cited By ~ 1

Author(s):

Hyuk-Jin Yoon ◽

Su-Hwan Yun ◽

Dae-Hyun Kim ◽

Jae Hee Kim ◽

Bong-Kwan Cho ◽

...

Keyword(s):

Unmanned Aerial Vehicles ◽

Wind Velocity ◽

High Speed ◽

Railway Bridge ◽

High Speed Train ◽

Box Girder ◽

Railway Bridges ◽

High Speed Trains ◽

Thrust Measurement ◽

Girder Bridge

Imaging devices attached to unmanned aerial vehicles (UAVs) are used for crack measurements of railway bridges constructed for high-speed trains. This research aims to investigate track-side wind induced by high-speed trains and its effect on UAV thrust near the railway bridge. Furthermore, the characteristics of train-induced wind in three axial directions along a track, wind velocity, and the effect of train-induced wind on the UAV thrust were analyzed. This was achieved by installing 3-axis ultrasonic anemometers and a UAV thrust measurement system on top of a PSC box girder bridge. The changes in the train-induced wind velocity were monitored along the train travel, width, and height directions. The train-induced wind was measured at distances of 0.8, 1.3, 2.3, and 2.8 m away from the train’s body to analyze wind velocity based on distance. It was found that the maximum wind velocity decreased linearly as the distance from the train’s body increased. The UAV thrust increased by up to 20% and 60%, owing to train-induced wind when the leading and trailing power cars of a high-speed train passed, respectively. Thus, it is necessary to conduct further research to develop robust control and a variable pitch-propeller that can control thrust.

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Application of Experimental Modal Analysis Method in Researching of Mechanical Structure Dynamic Characteristics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.694-697.370 ◽

2013 ◽

Vol 694-697 ◽

pp. 370-373

Author(s):

Zhang Yu ◽

Wen Zheng Cai

Keyword(s):

Modal Analysis ◽

Natural Frequency ◽

Dynamic Characteristics ◽

High Speed ◽

Experimental Modal Analysis ◽

Analysis Method ◽

Mechanical Structure ◽

Vibration Resistance ◽

Structural Rigidity ◽

Structure Dynamic

With the purpose of realizing the analysis of mechanical structure dynamic characteristics and inhibit vibration and noise, combined with the analysis of a certain type of high speed sewing machines vibration characteristics, we carry on the concrete experimental modal analysis, and compare the results of the experimental modal analysis with the results of spectrum analysis. The analysis results show that the second order natural frequency of the shell is close to two octaves under the normal working speed of sewing machine and it will lead to resonance. Enhancing the structural rigidity and the natural frequency under this modal to avoid resonance frequency is the key to improve vibration resistance of the structure.

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Determination of the optimal span length for a railway bridge crossed by various types of high-speed trains

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409714549083 ◽

2014 ◽

Vol 230 (2) ◽

pp. 531-543

Author(s):

Jeong-Rae Cho ◽

Kilje Jung ◽

Keunhee Cho ◽

Jong-Won Kwark ◽

Young Jin Kim ◽

...

Keyword(s):

High Speed ◽

Span Length ◽

Railway Bridge ◽

High Speed Trains ◽

Optimal Span

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Fatigue assessment of a composite railway bridge for high speed trains. Part II: Conditions for which a dynamic analysis is needed

Journal of Constructional Steel Research ◽

10.1016/j.jcsr.2012.11.014 ◽

2013 ◽

Vol 82 ◽

pp. 246-254 ◽

Cited By ~ 12

Author(s):

K. Liu ◽

H. Zhou ◽

G. Shi ◽

Y.Q. Wang ◽

Y.J. Shi ◽

...

Keyword(s):

Dynamic Analysis ◽

High Speed ◽

Railway Bridge ◽

Fatigue Assessment ◽

High Speed Trains

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Ground-Based Radar Interferometry for Monitoring the Dynamic Performance of a Multitrack Steel Truss High-Speed Railway Bridge

Remote Sensing ◽

10.3390/rs12162594 ◽

2020 ◽

Vol 12 (16) ◽

pp. 2594

Author(s):

Qihuan Huang ◽

Yian Wang ◽

Guido Luzi ◽

Michele Crosetto ◽

Oriol Monserrat ◽

...

Keyword(s):

Dynamic Behavior ◽

High Speed ◽

Point Clouds ◽

Vibration Monitoring ◽

Dynamic Monitoring ◽

Railway Bridge ◽

High Speed Railway ◽

Testing Procedures ◽

Microwave Radar ◽

High Speed Trains

With the continuous expansion of the high-speed railway network in China, long-span railway bridges carrying multiple tracks demand reliable and fast testing procedures and techniques. Bridge dynamic behavior analysis is a critical process in ensuring safe operation of structures. In this study, we present some experimental results of the vibration monitoring of a four-track high-speed railway bridge with a metro–track on each side: the Nanjing–Dashengguan high-speed railway bridge (NDHRB). The results were obtained using a terrestrial microwave radar interferometer named IBIS-S. The radar measurements were interpreted with the support of lidar point clouds. The results of the bridge dynamic response under different loading conditions, including high-speed trains, metro and wind were compared with the existing bridge structure health monitoring (SHM) system, underlining the high spatial (0.5 m) and temporal resolutions (50 Hz–200 Hz) of this technique for railway bridge dynamic monitoring. The detailed results can help engineers capturing the maximum train-induced bridge displacement. The bridge was also monitored by the radar from a lateral position with respect to the bridge longitudinal direction. This allowed us to have a more exhaustive description of the bridge dynamic behavior. The different effects induced by the passage of trains through different tracks and directions were distinguished. In addition, the space deformation map of the wide bridge deck under the eccentric load of trains, especially along the lateral direction (30 m), can help evaluating the running stability of high-speed trains.

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Measurements of the Vertical Displacements of a Railway Bridge Using TLS Technology in the Context of the Upgrade of the Polish Railway Transport

Sensors ◽

10.3390/s19194275 ◽

2019 ◽

Vol 19 (19) ◽

pp. 4275 ◽

Cited By ~ 9

Author(s):

Pelagia Gawronek ◽

Maria Makuch ◽

Bartosz Mitka ◽

Tadeusz Gargula

Keyword(s):

High Speed ◽

New Technologies ◽

Measurement Techniques ◽

Vertical Displacement ◽

Structure Stability ◽

Steel Bridge ◽

Railway Bridge ◽

Land Surveying ◽

High Speed Trains ◽

Railway System

The railway system in Poland is undergoing technological transformation. The development of the Polish railway system concerns not only high-speed trains but also infrastructure. The steel bridge is the most popular type of railway bridge in Poland. Most of them were built in the 1950s and 1960s. According to the recommendations in place in Western Europe, such railway bridges should be reviewed in terms of their fitness for use with modern high-speed trains. The modern technological revolution affects not only the railway, but also developments in displacement and deformation measurement techniques. New technologies provide more objective measurement results and accelerate results processing. They also facilitate the non-contact measurement of bridge structure stability. The authors investigated the vertical displacement of an old steel railway bridge in three different, specific case studies of terrestrial laser scanning data application. Then, the results of 3D data were compared with traditional land surveying results. The scientific results led to a conclusion that a strictly determined methodology of the measurement and analysis of a terrestrial laser scanner results supported by traditional land surveying techniques facilitates the determination of the vertical displacement of bridges with acceptable accuracy.

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Dynamic Analysis of an Existing Arch Railway Bridge According to Eurocodes

Archives of Civil Engineering ◽

10.1515/ace-2015-0100 ◽

2016 ◽

Vol 62 (4) ◽

pp. 99-118 ◽

Cited By ~ 4

Author(s):

R. Oleszek ◽

W. Radomski

Keyword(s):

Dynamic Analysis ◽

Modal Analysis ◽

Structural Dynamics ◽

High Speed ◽

Bending Moments ◽

Railway Bridge ◽

High Speed Train ◽

Arch Bridge ◽

Railway Bridges ◽

Structural Solutions

AbstractModern regulations concerning railway bridges are based on the approach of structural dynamics, which is described in PN-EN standards. This paper presents the results of theoretical dynamic analysis of the HSLM-A train set loading on the structure of a pre-stressed concrete arch bridge - the first railway bridge of its type which was built in Poland (completed in 1959). The recommendations of PN-EN have been followed and modal analysis was carried out to define the sensitivity of the structure to chosen eigenforms. Additionally the paper presents a course of calculations and the conclusions obtained from the analysis of displacements, accelerations, and bending moments induced in the structure through a simulated passage of a high-speed train in the context of the requirements of PN-EN Standards. The conclusions from the current calculations can be used for dynamic analysis of bridges of similar structural solutions.

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