• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1026-1032
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• 2004

The objective of this study is to confirm the field application of coarse aggregates technology mixtured with high strength mortar under the rail. In the present study, the field tests are performed to find the field state and aggregate gradations and the laboratory tests are performed to find the compressive strength of the pre packed concrete cylinder specimens and the core specimens obtained at the field.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.223-228
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• 2001

In this paper, crashworthiness of the KHST carbodies is evaluated by numerical simulation under the SNCF accident scenario (collision against a movable rigid mass of 15 ton at 110 kph) and the scenario of train-to-train collision at 30 kph. The numerical results of the several simulations, such as the accident collided against a deformable dump truck of 15 tons at 110 kph, the driver's dummy analysis using the integrated analysis method, and the accident of train-to-train collision for the first three units at 30 kph, show good performances in the viewpoint of energy absorption and survival space.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.519-525
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• 1999

This paper describes a crashworthy design for the front structure of KHST (Korean High Speed Train) under the SNCF accident scenario (collision against a movable rigid mass of IS tons at 110 km/h). The front structure designed in a new concept shows good behaviours in crashworthy point of view. It collapses in a progressive and well-controlled fashion. To evaluate the design by considering real situations, the power-car is simulated for accidents collided against a dump truck of 15 tons at 110 km/h. The front end structure of it shows a good response on crashworthiness.

• International Journal of Railway
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• 제3권4호
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• pp.126-133
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• 2010

The thermal buckling analysis of curved continuous welded rail (CWR) is studied for the lateral buckling prevention. This study includes a thermal buckling theory which accounts for both thermal and vehicle loading effects in the evaluation of track stability. The parameters include rail size, track lateral resistance, track longitudinal and torsional stiffnesses, initial misalignment amplitude and wavelength, track curvature, tie-ballast friction coefficient and truck center spacing. Parametric studies are performed to evaluate the effects of the individual parameters on the upper and lower critical buckling temperatures. The results show that the upper critical buckling temperature is highly affected by the uplift due to vehicle loads. This study provides a guideline for the improvement of stability for dynamic buckling in curved CWR track.

• 한국철도학회논문집
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• 제7권1호
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• pp.37-48
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• 2004

In this paper, I explain the situations and problems which are focused on the rail freight system. We have a many problems, which have been showed the long freight logistics time, and inadequate fare system. And rail freight system does not have a efficient marketing system, and unit load system. Therefore rail freight has been decreased modal share, which is estimated from 9.65% in 1995 to 6.25% in 2001(ton base). Recently, EU nations and America rail freight system reveals a good outcome, which keeps the balance in the black. The main factors which go into the black, is the enlargement the investment in rail freight and efficient management focusing on the unit load system, fare system, and personnel management. I suggest the several improvement ways, which will be helpful to advance the rail freight system. Fistly, I suggest the speed up the freight rail and efficient fare system. Secondly, I propose the unit load system and the regulation the truck focusing on curtailment of the social cost. Lastly, I make an overture of establishment the comprehensive logistics system.

• 한국철도학회논문집
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• 제16권5호
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• pp.418-429
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• 2013

본 연구는 우리나라에서 화물의 운송수단별로 통행시간가치가 어느 정도 크기로 수렴되는 것이 적정한 지를 평가해보고, 아울러 시간가치를 어느 정도의 범위 안에서 적용하는 것이 합리적인지를 강구하였다. 연구의 결과 화물차를 이용한 도로운송은 적정 시간가치의 크기와 범위의 도출이 가능하나, 철도와 내륙수로 해운, 항공운송 등은 도출에 한계가 있었다. 도로운송 화물의 적정 시간가치 크기는 20,000원/대 시간이며, 가변적 요소까지를 감안하였을 때 적용 가능한 범위의 분포는 17,000~23,000원/대 시간이다. 아울러 시간가치의 산정 방법은 도로운송의 경우 임금율법이 적정하나 철도, 내륙수로, 해운, 항공 운송 등은 적용 목적과 대상 화물의 특성을 반영하여 한계대체율법을 사용하는 방안이 합리적임을 제시하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.255-262
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• 2011

2010년 철도화물 수송톤수는 약 39백만 톤이며, 이 중 석탄수송은 약 6.2백만 톤으로 전체 철도수송의 약 15.7%를 차지하고 있다. 또한 철도화물 수입 중 석탄수송이 약 15.8% 수준인 517억 원으로 철도수송 품목에 있어서 수송량 및 수익에 있어서 3번째로 큰 비중을 나타내고 있다. 그러나, 철도수송에서 큰 비중을 차지하고 있는 석탄은 정부의 무연탄 감산정책과 주로 트럭운송에 의지하는 비발전용 무연탄에 대한 우선 공급으로 철도수송이 크게 감소하고 있으며, 이에 대해 석탄취급이 많은 강원권 물류 수송수익에 큰 영향을 주고 있다. 이에 따라 본 연구에서는 강원권 화물운송 중 석탄수송이 감소하는 근본적인 원인에 대해 살펴보고, 이를 해결할 수 있는 방안에 대해 살펴보았다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.395-400
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• 2007

LRT(Light Railway Train), which is a intermediate system of train and bus, is arose for the solution of subway construction cost and the transportation capacity of bus. LRT was introduced in 1980's. About 30 local governments are plan to introduce LRT or constructing LRT, at present. AGT(Automated Guide-way Transit) system, which is a kind of LRT, is operated without driver. Rubber wheeled AGT system can reduce the noise and vibration compare to steel wheeled AGT, so it is estimated as ideal transportation system for urban area. And live loads at bridge are classified as the static load of vehicle and the dynamic wheel contact load which is occurred from the interaction of bridge and vehicle vibration, and the surface roughness. In the case of AGT system, the dynamic increment factor of bridge is greater than the normal train bridge and roadway bridge, because, the weight of AGT vehicle is more light that the train of truck. The exact method for dynamic increment factor is experiment. But this method is needed much money and time, moreover, this method cannot be adopted in design. Therefore, a simulation program for the interaction of AGT bridge, vehicle and surface roughness was developed, in this study. And the program was verified by experiment. As a result, the accuracy of the simulation program can be verified.

• International Journal of Railway
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• 제6권3호
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• pp.95-106
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• 2013

Earthborne vibrations are induced by construction operation such as pile driving, roadbed compaction, and blasting and also by transit activities such as truck and trains. The earthborne vibration creates the stress waves traveling outward from the source and can structurally damage nearby buildings and structures in the forms of direct damage to structure and damage due to dynamic settlement. The wave propagation characteristics depends on impact or vibration energy, distance from the source, and soil characteristics. The aim of this paper is to provide a comprehensive review on the mechanistic of earthborne vibration and the current practice of vibration control and mitigation measures. The paper describes the state of knowledge in the areas of: (1) mechanics of earthborne vibration, (2) damage mechanism by earthborne vibration, (3) calculation, prediction of ground vibration, (4) the criteria of vibration limits, (5) vibration mitigation measures and their performance, and (6) the current practice of vibration control and mitigation measures.

• 한국철도학회논문집
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• 제15권3호
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• pp.294-299
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• 2012

철도운송은 오랜 기간 동안 도로운송, 해상운송, 항공운송보다 친환경 운송수단으로 인식되어 왔다. 하지만 최근 디젤유를 사용하는 점화기관에서 배출되는 오염물질이 대기오염의 주범으로 밝혀지면서 사회적 문제로 인식되고 있으며 녹색성장을 위한 정부 정책으로 철도분야도 온실가스 배출의 감축 의무를 피할 수 없을 것으로 전망되고 있다. 또한, 지속적인 고유가는 운영비를 상승시켜 운영기관에 큰 부담이 되고 있다. 본 논문에서는 온실가스 배출 감소와 유류비 절감을 위해 운영기관 입장에서 화물열차의 경제속도를 결정하기 위한 방법론을 제안한다. 경제속도를 추정하기 위해 유류비, 화물열차의 시간가치, 탄소세를 고려하여 비용 함수를 추정하였다. 비용 함수를 바탕으로 화물열차의 경제속도를 도출하기 위한 식을 제안하고 유류비, 화물열차의 시간가치, 탄소세의 변화가 속도에 미치는 영향을 알아보기 위해 민감도 분석을 하였다.