선로이송 가설공법을 적용한 철도판형교 유도상화(III)

민지홍(ji-Hong Min),장준현(Jun-Hyun Jang),우용근(Jin-Yong Kim),김진용(Yong-Keun Woo) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.10

To install heavy structures in the railway bridges crane methods or launching methods using temporary structure have been applied. These methods are uneconomical because working yard is required temporary cut of rail system etc. In this study various construction methods has been developed which are suitable to the filed conditions. In the case of simple span structure like plate girder bridges the girder is loaded to troy system at the working yard and then transferred to the working place. To lift and lower the girder system a new transfer system was developed. Different methods each for simple span bridge girder and long span girder were developed and detailed work procedures were proposed. Using these methods the heavy structures can be installed with simple and safe work procedures and the construction cost and duration can be reduced.

강판을 사용한 보자리 내진 보강 연구

추희창(Chu Hee-Chang),박대희(Park Dae-Hee),우용근(Woo Yong-Keun),남보현(Nam Bo-Hyun) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.11월

The bridge bearings and girder seats, which transfer superstructure loads to substructure, are important parts in the bridge structures, especially railway bridges in which the live load to dead load ratio is large. Also, these parts are considered as one of the most critical connections when earthquake load is applied. Unlike the bridge bearings which are manufactured in the shop with strict quality controls, the girder seats are constructed in the fields and it is common to be found with severe damages due to railway loads and impacts. The beam seat damages cause strength reduction, especially for the horizontal load by earthquake and may not possess adequate strength for earthquake load. In the railway bridges, these damages start more rapidly than other bridges because the live load portion is large, the impact and horizontal load are huge due to the railway's high speed. These damages could be minimized if the load, which are applied to the girder seats, could be distributed into wider surface and the concrete face could be protected. The purpose of this strengthen method is to protect girder seat and reduce maintenance cost by longitudinally connect bridge bearings with steel plates and distributing superstructure reactions and earthquake loads into wider areas.

무도상 판형교 레일 장대화에 따른 궤도 유지관리 비교연구

남보현(Nam Bo-Hyun),장태철(Jang Tae-Cheol),우용근(Woo Yong-Keun),민경주(Min Kyung-Ju) 한국철도학회 2007 한국철도학회 학술발표대회논문집 Vol.- No.-

Form the application of long rail system the non-ballast steel plate bridges, fatigue strength increase and rail noise reduction can be expected. This is mainly form the reduction of the rail impact at the rail joint locations which already made to behave together from welds. In the high speed rail, application of long rail system is essential because without long rail system, the required serviceability level can not be achieved. But even with this long rail systems, the thermal expansion from the girder can not be absorbed in the normal bearing systems, and these expansion cause between girder and rail. Also unexpected rail buckling and fracture through rail thermal tension may happen. It was found through numerical analysis and field measurement that these problems can be avoided by semi-fixed bearing system. In this study, the benefits of non-ballast plate bridge through long rail system, especially at the point of girder stability, girder stiffness increase and bearing maintenance will be reviewed.

실물실험을 통한 PC-Slab합성 판형교의 성능비교연구

민경주(Min Kyung-Ju),이성욱(Lee Sung-Uk),김영국(Kim Yung-Guk),우용근(Woo Yong-Keun) 한국철도학회 2010 한국철도학회 학술발표대회논문집 Vol.2010 No.7

In the railway bridges, steel plate girder types are preferred due the high stability. Nevertheless, it has been pointed out that this type of bridge has problems such as, structural damages in the rail and girder seat, noise problem due to impact at the rail joint and excessive vibration. This vibration and/or deflection are mainly because insufficient stiffness of steel plate type of bridge. To resolve these problems, PC-Slab composite plate girder type which has simple process and economic cost, is proposed in this study. The static and dynamic experiment is performed by using the production of actual sized PC-Slab and abandoned steel plate girder. The object of this experiment is to verify the fact that girder stiffness increase and structural safety. The result of the experiment is used to analyze the effect of performance improvement of PC composite plate girder type. Using this method, economic rail maintainers, girder stiffness increase, and also speed/ride improvement even for existing rail could be expected by dynamic performance improvement. Additionally noise due to impact, deflection and vibration caused from long rails can be reduced.

온도에 의한 고속선 교량의 신축변위 거동 분석

박준오(Park Jun-O),진남희(Jin Nam-Hee),우용근(Woo Yong-Keun) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.11월

The amount of longitudinal displacement of a ballasted track bridge is affected by temperature as well as span length of bridge, axial force of continuous welded rail, fastening force of rail fastening device and type of shoe, etc. This longitudinal displacement of a bridge changes the density of ballast at the end of a bridge, and finally causes the track irregularities like longitudinal level of rail. This study analyzes the effect of temperature on the longitudinal displacement of Gyeongbu high speed railway bridges. Among the health monitoring system in Gyeongbu high speed line, longitudinal displacement meters and thermometers have been installed in 2 prestressed box girder bridges which have different span lengths. By comparing the longitudinal displacements of these bridges with daily and long termly ambient air temperature changes from the long term measured data, the effects of temperature change on bridge expansion are analyzed and the times when maximum expansion or contraction happens are identified.

교량상 레일 조건에 따른 레일 및 교량의 안전성 연구

민경주(Min Kyung-Ju),김영국(Kim Young-Kook),우용근(Woo Yong-Keun) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.5월

In railway bridges, various loads including train load, transverse load and braking force are applied to continuous CWR or semi-continuous longer rail located on non-continuous bridge superstructures. The rail-girder interaction due to thermal expansion is also very complex in railway bridges because the thermal characteristics for each of the rails and girder are quite different. Recently, the bridge retrofits for seismic loads were performed on bridges not designed for these loads. These retrofits may however have limitations with respect to rail-girder interactions because, in general these retrofits address issues related only to seismic loads. In this study of seismic evaluations for railway bridges, the load effects on the bridge rails from the road beds through the continuous rails shall be considered. Practical methods will be proposed which will increase the railway stability. For this, rail-girder interaction analyses due to train loads, temperature changes and seismic loads were performed and the results reviewed from a practical point of view.

균열 보수재료의 성능평가를 위한 실험적 연구

김찬문(Chan Mun Kim),박순응(Soon Eung Park),지현우(Hyun Woo Ji),우용근(Yong Keun Woo),정혁상(Hyuk Sang Jung) 한국철도학회 2014 한국철도학회 학술발표대회논문집 Vol.2014 No.10

본 연구에서는 균열 보수용 재료의 제품별 성능을 평가하기 위해 철도교량 보도부 균열 0.3mm이상의 균열 주입개소에 대해 현장 코어 샘플링 10개소를 시행하여 표면균열, 균열 깊이에 대한 에폭시 충진상태, 균열부의 부착력 등을 분석하는데 있다. 철도차량의 반복하중에 의한 진동 영향 및 계절적 특성을 고려하기 위해 균열보수 후 약 8개월이 경과한 다음 코어링을 실시하였으며 향후 철도교량의 균열 보수재료 선정 및 유지관리를 위한 기초자료로 활용하고자 한다. In this study, the surface cracks, epoxy filled state to the depth of cracks and the adhesion of cracks are analyzed in order to assess the performance of the materials for crack repair. For this, the 10 sites of field core sampling for cracking 0.3mm or more were conducted in the rail bridges crack injection sites. After eight months to repair cracks, the coring was performed to consider the impact of the vibration caused by cyclic loading of vehicle and also seasonality. The results can be used as the basic data for the selection of the crack repair materials and maintenance of the railway bridge in the future.

[미발표]실운행열차를 이용한 철도교의 재하시험 및 내하력 산정방법(Ⅱ)

민경주(Kyung-Ju Min),이성욱(Sung-Uk Lee),최일윤(Il-yoon Choi),우용근(Yong-Keun Woo) 한국철도학회 2012 한국철도학회 학술발표대회논문집 Vol.2012 No.5

철도교는 도로교와 다르게 일정한 선로에 따라 궤도위에서 종방향으로만 주행하므로 재하시험에서 하중조건이 비교적 단순하게 된다. 그러나 교량의 진동유발요소는 차량의 동작특성, 궤도의 종류와 상태, 교량의 동적거동특성 및 지간과 거더의 배치 등에 영향을 받는 등 다양하며, 열차의 종류나 속도의 영향을 크게 받게 된다. 기존의 철도교 재하시험은 열차설계 하중을 사용하므로 내하력 평가에서 궤도특성이 무시되며 켄트나 원심하중의 표현이 불가하다. 따라서 정확도가 저하되고 다양한 열차의 특성을 파악하는데 한계가 있었다. 본 연구에서는 철도교량의 내하력 평가에서 윤중을 측정하여 산정한 내하력을 기존방법과 비교 검토함으로써 운행열차를 이용하요 재하시험에 활용할 수 있고 재하시험의 정확도 향상시킬 수 있었다. 재하시험에서 측정된 윤중자료의 축적은 톤과톤수의 과학적인 산정이 가능하므로 교량 및 레일의 피로수명 산정에도 유용하게 활용될 수 있을것이다. In contary to roadway bridges, in the railway bridges, the loading case is much simpler in load tests because the train moves only on the rails within the designated location. But the gridge vibration can be caused from many sources include vehicle characteristic, rail system, bridge characteristics, bridge span and girder arrangements. In the existing load carrying evaluation methods, rail characteristic is not considered and the cant or centrifugal force effects cannot be considered. As a results the accuracy of the load evaluation is decreased and various characteristics of the train cannot be considered. In this study, measured axle weights of the in-service train were applied in the load carrying capacity evaluation to increase the accuracy of the evaluation. Based on the measured axle weights, the reasonable design loads for load carrying capacity calculation can be found and these data can be applied bridge and rail fatigue life evaluations also.

실운행열차를 이용한 철도교의 재하시험 및 내하력 산정방법

민경주(Min Kyung-Ju),이성욱(Lee Sung-Uk),우용근(Woo Yong-Keun),박훈규(Park Hoon-Gyu),남보현(Nam Bo-Hyun) 한국철도학회 2010 한국철도학회 학술발표대회논문집 Vol.2010 No.10

콘크리트궤도 노반침하에 대한 유지보수 방안

이일화(Il-Wha Lee),장승엽(Seung-Yup Jang),엄주환(Ju-Hwan Um),최원일(Won-Il Choi),우용근(Yong-Keun Woo) 한국철도학회 2012 한국철도학회 학술발표대회논문집 Vol.2012 No.10

토공구간에서 콘크리트궤도를 적용할 경우, 가장 중요한 사항은 노반의 침하를 적정수준으로 억제하는 것이다. 노반침하를 기준값 이내로 유지함으로써 차량 및 궤도의 주행안정성을 확보하고 유지보수 노력을 감소시켜야 한다. 콘크리트궤도는 기존 자갈도상궤도와 달리 침하가 발생하였을 경우, 궤도의 사용성 저하가 크고 대처 방안이 매우 제한적이기 때문에 장기적으로 침하를 엄격히 제한하여야 한다. 또한 유지보수단계에서 원활한 관리수준으로 억제하려면 이에 대한 합리적인 대책을 마련하는 것이 필요하다. 본 논문에서 이러한 침하와 관련된 문제점을 사전에 차단하고 효율적인 노반관리를 위한 유지보수방안을 제시하고자 하였다. An active application of concrete track is being expected for the future construction of Korean railroad. For the successful concrete track construction and operation in earthwork areas, the residual settlement should be reasonably maintained using the proper method. The maintenance is very difficult for excessive settlement on existing line, it is need to constrain the residual settlement reasonably. In this present paper, the maintenance system is suggested to reduce the settlement problem and to increase the maintenance efficiency in stage of the operation.