• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1248-1253
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• 2011

It is increasing construction of long span railway bridge with concrete track system for speed up of railway and efficient maintenance of track. As the sleeper of the concrete track system layed on a bridge is fixed on deck of the bridge, the displacement of the sleeper and deck is same. Therefore, the spacing between two sleeper installed at the end of the adjacent deck near the expansion joint of bridge becomes vary according to the longitudinal expansion of a deck by temperature change. By the way, if the spacing of sleepers become increase excessively, it causes large bending stress of in a rail, and it can leads failure or reduction of fatigue life of the rail. Further more, the excessive displacement of the rail may induce decrease ride comfort as well as corrugation of rail surface. Therefore, it is required to determine the allowable maximum sleeper spacing to prevent such problems. For the purpose, investigation on the influence factor on sleeper spacing for straight track was carried out. Variation of bending moment in a rail, wheel force, and the ratio of primary and secondary deflection of the rail according to sleeper spacing was investigated, and, as a result, the maximum allowable sleeper spacing at the bridge expansion joint was suggested.

• 한국철도학회논문집
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• 제9권6호
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• pp.746-752
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• 2006

The major objective of this study is to investigate the dynamic behavior evaluation of split PC sleepers for railway turnout by the field test. In railway engineering, a turnout is necessary to allow a vehicle to move from one track to another. So, turnout is required very complex railway technologies such as lolling stock, track. In reference to conventional line speed-up and improvement railway, accurate assembly of turnout affects travel ins qualify of turnout area and running safety. Because of heavy weight and a large volume of the long sleeper used to turnout and car limit, transport and the prerequisite for trouble-free transport of the factory pre-assembled major turnout components is achieved through division of long sleepers. The one of the advantages for using a split sleeper is to reduce the dynamic vibration according to the information of developed nations. Therefore, we investigate the characteristic of dynamic behaviors of split sleepers which are adopted for the first time to improve performance of turnout From the field test results of the split sleeper, it is evaluated that the modification of weight, material and stiffness compared with wood sleeper is very effective for the ballast safety. However, the decrease in vibration of split sleeper was not found out.

• 한국소음진동공학회논문집
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• 제25권9호
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• pp.620-627
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• 2015

Long continuous bridge deck can become contracted considerably as temperature drops, which can lead to a large expansion of sleeper span at the end of it. Since this huge sleeper span then can cause problems both with safety of train operation and structural stability of tracks, it is necessary to take the issue into consideration systematically in the designing process of the bridge. In this paper, an evaluation process through the analysis of train-track interaction was presented which can basically review the effects of the expansion of sleeper span at the end of long continuous bridge deck on the safety of the train and the structural stability of the track. The analyses of the interaction between the light rail train and tracks were carried out targeting the sleeper span as a main parameter. The safety of train operation and structural stability of tracks in a light rail system due to the expansion of the sleeper span were evaluated by comparing the numerical results with the related criteria.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.436-442
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• 2011

It is increasing construction of long span railway bridge with concrete track system for speed up of railway and efficient maintenance of track. As the sleeper of the concrete track system layed on a bridge is fixed on deck of the bridge, the displacement of the sleeper and deck is same. Therefore, the spacing between two sleeper installed at the end of the adjacent deck near the expansion joint of bridge becomes vary according to the longitudinal expansion of a deck by temperature change. By the way, if the spacing of sleepers become increase excessively, it causes large bending stress of in a rail, and it can leads failure or reduction of fatigue life of the rail. And also the excessive displacement of the rail may induce decrease ride comfort. Therefore, in order to prevent such problems, the allowable maximum sleeper spacing at a bridge expansion joint was mutually determined. And, the determination procedure of the maximum bridge expansion length based on the allowable sleeper spacing was suggested.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.1279-1286
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• 2006

It is very important to pay careful attention to construction of earthwork/tunnel transition zone for railway. The transition zone of the railway is the section which roadbed stiffness is suddenly varied. Differences in stiffness have dynamic effects and these increase the forces in the track and the extent of deformation. In this study, performance of transition zone was investigated through the field tests. The wheel loads and sleeper settlement were measured after installing field testing sections.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.739-745
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• 2004

In reference to conventional line speed-up and improvement railway, accurate assembly of turnout affects traveling quality of turnout area and running safety. Because of heavy weight and a large volume of the long sleepers and car limit, transport and construction of the P.C(prestress concrete) sleeper turnout is the most difficult process. the prerequisite for trouble-free transport of the factory pre-assembled major turnout components is achieved through division of long sleepers. So, in this paper we investigate structural safety of segmented sleeper which is adopted for the first time to improve performance of turnout and, new construction method.

• 한국철도학회논문집
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• 제13권2호
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• pp.214-221
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• 2010

철도 선로에서 대표적인 취약개소로 분류하고 있는 터널-토공 접속구간은 하부 지지강성의 차이로 인하여 강성이 작은 구간에서 더 큰 침하가 발생하여 선로의 부등침하를 발생시켜 지속적인 유지보수 작업을 실시하여야 한다. 본 논문에서는 실제 현장구간의 터널-토공 접속구간에 대하여 도상자갈부에 설치된 일반 침목을 약 20m 대형침목으로 교체 후 윤중과 침목 침하량을 측정하여 개선효과를 비교하였다. 또한 수치해석을 이용하여 침목 크기와 간격 등을 변화시켜 레일압력, 도상 침하량 그리고 도상압력을 비교하였다. 현장계측과 수치해석결과 대형침목으로 교체한 경우 일반침목에 비해 윤중변동율과 침하량 등에서 약 10%의 개선효과가 있는 것 을 확인할 수 있었다. 또한 수치해석결과 대형침목의 경우 일반침목에 비해 레일저부압력, 침목침하량, 도상압력이 각각 9.3%, 4%, 14.5% 감소되었으며, 이중에서 도상압력이 가장 많이 감소되는 것을 확인하였다.

• 문화기술의 융합
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• 제10권3호
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• pp.833-838
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• 2024

도시철도 침목플로팅궤도(STEDEF)는 침목상자와 침목방진패드를 이용하여 침목과 콘크리트 도상을 구조적으로 분리하여 콘크리트 도상에 전달되는 진동을 감소시키는 구조이다. 최근에는 20년 이상 공용중인 침목플로팅궤도의 침목방진패드 열화가 발생하고 있다. 이에 침목방진패드에 대한 성능을 평가하기 위해 침목방진패드 발췌 후 정적 스프링강성 시험을 수행하고 있다. 해당 평가기법은 사용 중인 침목방진패드를 반드시 교체한 후 평가를 수행한다. 그러나 궤도 고유진동수는 침목방진패드 스프링강성 및 콘크리트 도상의 융기와 침하에 따라 변화할 수 있다. 본 연구에서는 궤도 고유진동수를 평가하기 위해 모달시험기법을 사용하였다. 이를 위해 실험실 규모에서 침목상자 소재, 침목방진패드 스프링강성 및 콘크리트 도상 융기 및 침하에 따른 궤도 고유진동수를 모달시험을 이용하여 측정하였다. 침목플로팅궤도 고유진동수는 침목방진패드 스프링강성 변화에 따라 직접적인 영향을 받는 것으로 분석되었다. 또한 콘크리트 도상의 융기 및 침하에 따른 고유진동수 변화도 큰 것으로 나타났다. 따라서 본 연구에서 제시한 모달시험기법을 이용하여 침목방진패드의 열화 및 뜬 침목 평가 등에 활용할 수 있을 것으로 판단된다.

• 한국안전학회지
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• 제25권1호
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• pp.57-61
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• 2010

Formwork is a temporary structure that supports its weight and that of fresh concrete as well as construction live loads. Scaffoling is a temporary frame used to support people and material in the construction or repair of buildings and other large structures. It is usually a modular system of metal pipes, although it can be made out of other materials. Bamboo is still used in some Asian countries like China. The purpose of a working scaffold is to provide a safe place of work with safe access suitable for the work being done. In construction site, steel pipes are usually used as scaffolds. In this study, scaffolding systems which is changed according to sleeper and joist space were measured by buckling test. Buckling load of respective scaffolding system was analyzed by structural analysis program(MIDAS). Buckling load of scaffold with/without wall connection and footboard was got by test and structural analysis. According to these results，we know that scaffolding system of case 3 is suitable. Buckling load of scaffold with wall connection is higher than without wall connection. So wall connection is important in scaffoling systems. Footboard in the scaffolding systems is not effective against promotion of buckling load. Finally, the present study results will be used to design scaffolding systems safely in the construction sites.

• 한국철도학회논문집
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• 제15권3호
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• pp.251-256
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• 2012

고속철도 자갈궤도에서 궤도틀림을 체계적이고 효율적으로 관리하기 위해서는 뜬 침목구간에서 차량이 궤도에 미치는 동하중의 특성을 파악할 필요가 있으며 이를 위해서는 뜬 침목을 고려한 차량과 궤도의 동적 상호작용해석기법의 개발이 필요하다. 본 연구에서는 초기 레일의 처짐이 없는 경우 궤광자중에 의하여 발생한 레일처짐(궤도틀림)과 처진 침목과 자갈도상간의 침목 들뜸량을 계산할 수 있는 해석기법을 개발하였고, 궤도틀림과 침목 들뜸량을 동시에 고려할 수 있는 차량과 궤도의 해석기법을 개발하였다. 본 해석기법의 타당성은 타문헌에서 제시한 해석결과와 비교를 통하여 검증하였다.