• Journal of Korean Society of Steel Construction
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• v.12 no.4 s.47
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• pp.407-416
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• 2000

This paper presents the dynamical responses of the plate girder bridge subjected to moving load by experimental method. The upper slab of the plate girder bridges is modelled to the plate element and the girder to the beam element. The small-scaled vehicle model is manufactured as moving load and the acryl-bridge model as the plate-girder bridge. The dynamic responses of the plate-girder bridges under the moving load are obtained by the strain gauges, displacement measurements, accelerometer, and dynamic strain measurement. The maximum dynamic responses from the measured data are compared with those from the finite element method. The experimental model test can be used to obtain to the dynamic responses of the plate-girder bridges.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.94-101
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• 2019

Most of the existing rail structures have undergone a lot of aging since a considerable period of time has passed from completion. In particular, among existing railway bridges, many of the plate girder bridges are older bridges that have lived 40 to 60 years or more. Since the treadmill is directly connected to the girder without the ballast, the running load of the vehicle is directly transmitted to the bridge. Therefore, the shock and noise applied to the bridge are larger than those of the ballast bridge, and the dynamic shock and vibration are also relatively large. Therefore, it is very urgent to develop appropriate maintenance, repair and reinforcement technology for existing steel plate bridge. In this study, the authors introduced the characteristics of embedded rail (ERS) developed for improving the performance of the existing plate girder bridge and the techniques solving the vibration and noise problems. In order to evaluate the vibration and noise reduction performance of ERS, a non-ballast plate girder bridge with 5m length of sleepers installed and a plate girder bridge with ERS were fabricated. And, then, the vibration response generated under the same excitation condition was measured and analyzed. Also, the radiated noise analysis was performed using the vibration response data obtained from the experiment as the input data of the acoustic analysis model. As a result of experiments and analyses, it was confirmed that the plate girder bridge's vibration using ERS was reduced by 15.0~18.8dB and the average noise was reduced by 7.7dB(A) more than the non-ballast bridge.

• Journal of Korean Society of Steel Construction
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• v.18 no.4
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• pp.437-446
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• 2006

Open-steel-plate-girder(OSPG) bridges are one of the most prevalent bridge types among Korean railway bridges. They account for about 40% of all Korean railway bridges. However, the line-type bearings used for OSPG bridges generate several problems with respect to the bridges' dynamic behavior and maintenance. The replacement of the existing bearings with polyurethane disk bearings could be a possible solution to this problem. This type of disk bearing is an elastic bearing using a polyurethane disk. This study estimated the variations in the natural frequency of a bridge when disk bearings were installed and the bridge's dynamic behavior with a running locomotive and running trains. The first natural frequency of the bridge was 3% lower than that of the as-built bridge after the installation of the disk lower, respectively. Also, the second and third frequencies were 7 and 15% lower, respectively. The disk bearings increased the vertical displacement of the bridge, but the pure displacement, excluding the disk deformation, did not vary. The vertical acceleration did not increase when the disk bearing was installed, with trains running. The shear pin in the disk bearing reduced the lateral displacement and the acceleration of the bridge.

• Journal of Korean Society of Steel Construction
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• v.17 no.3 s.76
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• pp.295-306
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• 2005

In this study, the dynamic characteristics of the two open-steel-plate-girder bridges was analyzed using the pads' stiffness estimated in the previous accompanying paper.Also, it was determined that the variation in the dynamic behavior of the two bridges due to the pads corresponds to the codes describing the restriction for the steel bridges' behavior.The pads installed at the bridges increase the displacement at mid-span.However, the increase does not exceed code restrictions and does not have an adverse effect on the riding quality of the running trains. The natural and Chloroprene rubber pads are not suitable for bridge bearings since they are more deformed than the code regulated ones.

• Journal of the Korean Society for Railway
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• v.15 no.1
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• pp.62-70
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• 2012

Dynamic behaviors of line type bearings, spherical bearings and disk bearings which are being used for railway steel bridges are investigated, and that of the bridges is also analyzed. For the purpose, the vertical displacements of the three bearings including fixed and expansion type are measured and analyzed. Also, the deformation of the PTFE plate placed inside of spherical and disk bearings of expansion type is measured and its effect on the dynamic behavior of the bridges is discussed. The up-lift phenomenon at the bearings installed for the steel bridges is estimated. The vertical displacements at mid-span of the bridges are compared according to the bearing types. Finally, the 1st mode natural frequencies are estimated and the relationship to the vertical displacement is discussed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.6
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• pp.711-721
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• 2009

This study proposed digital close-range photogrammetric technique to measure deformation of I-plate-girder bridge. To compare deformation-measurement using the proposed method, a loading tester is used in the same time. As results, deviations of measuring values between the two methods range from 1mm to 2mm, and we could find-out simultaneously deflection and torsion of I-plate girder by repeated load of train. Then this study verified a measuring feasibility of I-plate-girder deformation by the proposed method. This may be alternative method of precise-stability inspection and manpower inspection.

• Journal of the Korean Society for Railway
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• v.11 no.2
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• pp.165-175
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• 2008

Line type rigid bearings for Open-Steel-Plate-Girder railway bridges have several problems in service, and they are unstable structurally. A series of lateral resistance tests were performed for a retrieved line type bearing. A spherical bearing with advanced maintenance-capability and a device to resist the up-lift was developed and replaced the existing ones. An experiment of maintenance for a new spherical bearing under real Open-Steel-Plate-Girder bridge was conducted and their good maintenance performance was proved. Also, a test against up-lift was performed for the bearing. The dynamic behavior of the bridge was measured and analyzed for the two cases of the existing and replaced bearings. Therefore, the suitability of the new spherical bearings on the railway bridge was improved.

• Journal of The Korean Society For Urban Railway
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• v.6 no.4
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• pp.327-337
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• 2018

Since the track of the ballastless steel plate girder bridge is connected to a main girder without a deck and a ballast, the impact generated by train passage is transferred directly to bridge main members, and it can cause frequent damage of the bridge as well as higher noise and vibration level. Applying the CWR (Continuously Welded Rail) technology can reduce this structural problems, and, to this end, it is necessary to understand the characteristics of factors influencing vehicle-track or track-bridge interaction. In this paper, experimental study results are presented for examining the longitudinal resistance characteristics of the track, including a rail fastener, a sleeper fastener, and a track skeleton, installed on a ballastless steel plate girder bridge. The experiment is conducted using a disposed bridge from service, which is transported to a laboratory. The experimental results show that the rail fastener satisfies the performance criteria of the longitudinal resistance presented in KRS TR 0014-15, and the longitudinal resistance of old and new type sleeper fasteners is higher than the values provided in the existing research. Also, the unloaded longitudinal resistance of the ballastless track is between the ballast and the concrete tracks.

• Computational Structural Engineering
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• v.12 no.2
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• pp.110-117
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• 1999

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.114-120
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• 2018

Recently, the plate girder bridge is offen designed a temporary bridge for underground roadway construction have not interrupt railroad operation. The integral support plate girder bridge which have longitudinal girder and cross-girder is improved workability and reduction cost and of construction time. The cross beam of the integral support plate girder bridge has a normal box shape to distribute load on the main girde to end both side girder. In this study, On the change to the web distance of the cross box shows characteristics of related to the stresses and displacements on the flange and web plate. Afterward, the various analysis contributed to the safety improvement of crossbeam of the integral support crossbeam plate girder bridge.