• International Journal of Railway
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• v.3 no.3
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• pp.83-89
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• 2010

This paper attempts to extract the fundamental dynamic properties, i.e. natural frequencies, damping ratios of the 48 m-long, $20^{\circ}$ skewed real bridge with PSC girders wrapped by a steel plate. The forced vibration test is achieved by mounting 12 Hz-capacity of artificial oscillator on the top of bridge deck. The acceleration histories at the 9 different locations of deck surface are recorded using accelerometors. From this full-scaled vibration test, the two possible resonance frequencies are detected at 2.38 Hz and 9.86 Hz of the skewed bridge deck by sweeping a beating frequency up to 12 Hz. The absolute acceleration/energy exhibits much higher in case of higher-order twist mode, 9.86 Hz due to the skewness of bridge deck which leads asymmetric situation of vibration. This implies the test bridge is under swinging vertically in fundamental flexure mode while the bridge is also flickered up and down laterally at 9.86 Hz. This is probably by asymmetric geometry of skewed deck. A detailed 3D beam-shell bridge models using finite elements are performed under a series of train loads for modal dynamic analyses. Thereby, the effect of skewness is examined to clarify the lateral flickering caused by asymmetrical geometry of bridge deck.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.541-544
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• 1999

The main objective of this study is to develope the PSC-I girder for long span bridge. This study investigates the structural behavior of Postcracking stage and efficiency of proposed PSC-I girder using 1/2 scaled prototype beam specimen. Three specimens are tested under three point static loading system. Ideally, the Load-displacement relationship is trilinear. The crack patterns and failure mode of each specimen are reported in this paper and they are compared to each other with ductility and strength.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.291-296
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• 1998

In the present study, the high strength concrete which is adequate for the long span PC beam above 40 meters has been developed. The optimum cement for high strength concerete was selected through laboratory tests and in-situ mock-up applications. The optical concrete mix design was performed, and the properties of fresh concrete and hardened concrete have been investigated. These results of laboratory study are analized and compared to domestic and foregn design codes and specifications. Finally, the developed high strength concrete was applied to half-scale PSC beams and showed good applicability in field conditions. It is conclude that hte developed high strength concrete can be applied to civil and architectural structures in the field applications.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.1
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• pp.1-9
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• 2022

Semi-integral abutment bridges are a type of integral abutment bridges. These bridges eliminate expansion joints on the structure and can be used in situations not suitable for full-integral abutment bridge. Moreover, Semi-integral bridges have excellent maintenance and can be economically constructed. This study is about precast wall-type blocks at each end which provide lateral support for PSC girder, as well as acting as retaining walls to resist longitudinal movement of semi-integral abutment bridge. The end-diaphragm connection between ended blocks of PSC girders can be achieved by in-suit nonshrinkage concrete. The results show that 3-point experiment of end-diaphragm beam have an acceptable performance which is so better than results of structural design. Moreover, the effects of backfill soil on semi-integral abutment bridge constructed are analyzed the behavior according to the temperature changes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.2
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• pp.115-124
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• 2003

A prestressed concrete slab bridge is analyzed by the specially orthotropic laminates theory. Both the geometry and the material of the cross section of the slab are considered symmetrical with respect to the mid-surface so that the bending extension coupling stiffness, $B_{ij}=0$, and $D_{16}=D_{26}=0$. Each longitudinal and transverse steel layer is regarded as a lamina, and material constants of each lamina is calculated by the use of rule of mixture. This bridge with simple support is under uniformly distributed vertical and axial loads. In this paper, the finite difference method and the beam theory are used for analysis. The result of beam analysis is modified to obtain the solution of the plate analysis.

• Journal of the Korea Concrete Institute
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• v.16 no.5 s.83
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• pp.709-717
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• 2004

The existing AASHTO Standard Specification have some inadequacies in expressing wheel load distribution of bridge which has specific shape of curved bridge instead of straight bridge. Thus, this research presented the finite element analysis and modelling technique of prestressed concrete girder bridge having curved slab and the expression of wheel load distribution was suggested as the ratio of bending moment utilizing the result of finite element analysis of prestressed concrete girder bridge having cowed slab. The considered parameter of girder distribution expression is the curvature of slab, span length, girder space, cross beam space and number of lanes. Though the suggested girder distribution expression is generally underestimated below AASHTO Standard Specification, once the curvature of slab increases, the suggested expression gets larger than AASHTO LRFD Standard Specification.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.545-551
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• 2006

Along with the steady development of Korean Railway construction technology, Contemporary society needs more modernized structures which can meet not only structural value but also aesthetic and environmental value. To follow this demand of society, Pre-Stressed Concrete U-girder bridge(Somg-Lim Gyo, L=330m) is introduced in 'JINJOO-KWANGYANG RAILWAY CONSTRUCTION PROJECT'. On the environmental point of view, the huge noise due to the operation of train can be reduced remarkably by the side beam of U-girder which is high enough to substitute soundproofing wall. Moreover, by aesthetic variation of the shape of outer beams and coping of piers, the exterior view of the bridge can be improved and in accordance with surroundings. Pre-Stressed Concrete U-Girders which are built up above the outer sides of slab deck make easier to secure the clearance of a bridge and make it possible to lower the distance of centroid between superstructure and railroad tracks.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.519-524
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• 1999

A bulb-tee sectioned girder is proposed for long span bridge exceeding 40 meters. The proposed bulb-tee girder is developed by non-linear analysis process. This study investigates the structural behavior and efficiency of proposed bulb-tee sectioned girder using 1/2 scaled prototype beam specimen. Three specimens are tested under three point static loading system. The crack patterns, failure mode and ultimate load capacity of each specimen are reported in this paper and they are compared to each other.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.169-170
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• 2010

This paper mainly investigates the adequate number of cross beams at the IPSC(Incrementally PreStressed Concrete) girder bridge. The length of span was fixed to 50m and FE model was analyzed by using the ABAQUS program. The models for the numerical tests result in the cases whose number of cross beam are respectively 2, 3, 4, and 5. All of the results of proposed numerical tests satisfy the current specifications. Also, based on the results, we can determine the optimal number of cross beam for more economic design and improvement in constructability.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.412-419
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• 2002

This paper presents a parametric study on the behavior of integral abutment PSC beam bridge. An integral abutment bridge is a simple span or multiple span continuous deck type bridge having the deck integral with the abutment wall. The rational structural model and design load combinations accounting for each construction stage are proposed. It can be used for defining the effect of earth pressure and temperature change in the design process including for determining maximum flexural responses. The bending moment at each response location due to the design load combination is investigated according to the change of flexural rigidity of piles and abutment height. The flexural responses of proposed model are computed for the cases of applying the Rankine passive earth pressure and the earth pressure based on the soil-structure interaction respectively, and the results are discussed.