• Computational Structural Engineering
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• v.12 no.4
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• pp.69-69
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• 1999

Design of Dangsan Steel Railway Bridge(a part of Seoul Subway Line NO. 2), which is supposed to be replaced after its 15years survice, was done, and the reconstruction has begun in Dec. 1997. The design include new superstruc-ture and bridge piers, retrofitting of the foun-dation, rail system, electric and signal, etc. In this paper, design of the structure is mainly summarized. The main span superstructure, across Han river, is composite section which is com-posed of steel box and reinforced concrete deck slab with 9 span continuous. The superstructure for the approaches is bottom througth type 2-cell steel box girder with steel floor system and concrete deck slab with 3 or 4 span continuous. The bridge piers was planned to be reconstructed based upon the result from the various investi-gations, while the foundation(cassion and pile foundation) was planned to be retrofitted. For superstructure erection, the method of combination of barge bent and heavy lifting and the launching truss method was investigated for the main span and approach spans, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.985-990
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• 2001

The widened Seoul-Bridge is the first continuous 8-span prestressed concrete(PSC) girder bridge in domain. The construction sequence of the bridge consists of S steps in a large way. The measuring in construction stage includes the determination of the allowable fluctuation value of beam stress in each step and the measurement beam stress during prestessing. The measured tendon prestress force was compared with the design value. When it was compared with the analytic result, the difference between the measured stress and the analytic stress was below allowable error. The friction loss and the anchorage slip loss of the tendon prestress force was lower than the design loss value.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.349-356
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• 1998

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross sections and with arbitrary boundary conditions was developed and reported by Kim, D. H. in 1974. In this paper, the result of application of this method to the three span continuous reinforced concrete bridge with elastic intermediate supports in presented. Such bridge represents either concrete or sandwich type three span bridge on polymeric supports for passive control or on actuators for active control. Any method may be used to obtain the deflection influence surfaces needed for this vibration analysis. Finite difference method is used for this purpose, In this paper. The influence of the modulus of the foundation and $D_{22}$, $D_{l2}$, $D_{66}$ stiffnesses on the natural frequency is thoroughly studied.d.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1057-1064
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• 2004

For New In-Cheon Airport. South Approach Section of Young long Great Bridge is to be special concerned to CWR due to substructure was already constructed former railroad bridge design specification. So we applied maintenance free system and CWR (Continuous Welded Rail) by ZLR(Zero Longitudinal Restraint) at bridge expansion joint part. This thesis generally introduce for CWR by ZLR at South Approach Section of Young long Great Bridge.

• Journal of Korean Society of Steel Construction
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• v.17 no.3 s.76
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• pp.317-324
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• 2005

The specially orthotropic plate theory is used to analyse three-span continuous composite slab bridges with elastic intermediate supports. A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross sections and with arbitrary boundary conditions, was developed and the result of application of this method to the three-span continuous composite slab bridges with elastic intermediate supports is presented. This type of bridge represents either concrete or sandwich type three-span bridge on polymeric supports for passive control or on actuators for active control. Any method may be used to obtain the deflection influence surfaces needed for this vibration analysis. The finite difference method is used for this purpose in this paper. The influence of flexural stiffnesses and the modulus of the foundation are studied.

• Journal of Korean Society of Steel Construction
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• v.17 no.2 s.75
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• pp.183-194
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• 2005

In the previous construction method of continuous preflex composite girder bridge, we raised the inner support, and cast slab concrete innegative moment section, then lowered it to introduce compressive force in the slab. There were a few problems in the process such as the time required in raising the support and the bending of the camber. Therefore, this paper represents an improved construction method of continuous preflex composite girder by only moving downward the inner and outer supports to figure out problems in previous construction method. This paper proposes a design formula to find a proper cross section of preflex girder.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1444-1451
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• 2010

This paper aims for proposed the deflection limit on vibration serviceability of high-speed railway bridges considering the exposed time duration when a train passes a railway bridge. For this purpose, bridge-train transfer function was derived and bridge-train interaction analysis was performed by using the derived function. The vertical acceleration signals of passenger cars obtained from bridge-train interaction analysis were compared with them from the bridge-train transfer function by moving constant force analysis. Therefore it was estimated possible to induce the comfort deflection limit of railway bridge by using bridge-train transfer function. The deflections by moving force of single span bridge and continuous bridge were assumed as sine and haversine wave. The deflection limit on vibration serviceability of high-speed railway bridges considering the exposed time duration can be expanded using bridge-train transfer function and bridge comfort limit considering serviceability due to bridge vibration. And it was compared to other allowable deflection limits of railway bridge design specifications.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.555-564
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• 2013

An effective method was proposed in this study which can improve the strengthening effect of continuous girder bridges by external tendons. The improvement of the proposed strengthening method in comparison with conventional methods was analyzed by applying equivalent load concept. In order to verify the strengthening effect, the enhancement of load-carrying capacity achieved by external prestressing was investigated through the test of continuous beams that were or were not strengthened by the external prestressing. The continuous beams were fabricated by making the deck slab continuous according to general construction practice of an actual concrete girder bridge. The test results showed that the deflections and strains of the strengthened beam were significantly reduced when comparing with those of the non-strengthened beam for the same level of external loads, and the stiffness of the member increased by strengthening. In particular, it was verified that the proposed method can effectively reduce the tensile stresses of the deck caused by negative moment at the intermediate supports of a continuous bridge.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.39-46
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• 2023

In this study, the dynamic behavior of friction bearings of PSC (Pre-Stressed Concrete) box train continuous bridge was numerically analyzed at 10 km/h intervals up to 600 km/h according to the increasing speed of the next-generation high-speed train. A frame model was generated targeting the 40-meter single-span and two-span continuous PSC box bridges in the Gyeongbu High-Speed Railway section. The interaction forces including the inertial mass vehicle model with 38 degrees of freedom and the irregularities of the bridge and track were considered. It was calculated the longitudinal displacement, cumulative sliding distance and displacement speed of the bridge bearings at each running speed so that compared with the dynamic behavior trend analysis of the bridge. In addition, long-term friction test standards were applied to evaluate the durability of friction plates.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.445-450
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• 2007

CWR(Continuous Welded Rail) and bridge interaction produce rail force, bridge displacement and rail/bridge relative displacement. Each of these has limitation by many codes. In this paper, analysis of interaction has been carried out by using foreign codes(UIC 774-3 R code of Europe etc.) because there is no code about interaction between rail and bridge in Korea. Recently, railway bridges with CWR has been constructed for structural and economical reasons. When designer plans railway bridges, design a bridge model first and then investigate railway forces and displacement by interaction analysis. If these results go out bounds from limitation, designer plans railway bridges again and again. In this paper, using the parametric study on CWR and railway bridge interaction, railway bridge parameters such as length of bridge span, area of bridge, moment of inertia, stiffness of pier, etc. are presented. It helps preliminary design of railway bridges.