• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.404-411
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• 2007

Reinforced roadbeds are valued from the point of view of maintenance as well as enhanced mechanical capacity. They support more train load and less transmit to the sub-layers than general roadbeds. Also, the lateral sloping surface of the reinforced roadbed and its low permeability, achieved by the controlled compaction, increase drainage capability and prevent the softening of sub-layers. In the study, a series of cross-hole tests was performed to observe the temporal changes in the stiffness of reinforced roadbeds, if any, due to the cyclic loading of trains and alternating rainy and frozen seasons at Pyeong-taek experimental site. The three types of reinforced roadbed materials are slag, crushed stones, and soils, and the thickness of all the reinforced roadbeds is 0.8m. The stiffness of the slag and soil reinforced roadbeds was not changed or slightly decreased. The stiffness of the crushed stone was somewhat increased and is inferred to being densified close to surface.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1056-1061
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• 2007

Railroad roadbed was consisted into structure types that earthwork, tunnel, bridge and joint sections. Joint section was affected a large factor confidence and safety of the train running by stiffness transition zone that track substructure stiffness change section as like between tunnel and earthwork from ballast track to concrete track. These problems are the results of increased dynamic wheel loads, which also lead to wear and tear on vehicle components and contribute to poor ride quality. The study presented in this paper was conducted on model test by using Wheel Moving Loading System.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.569-574
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• 2007

The paper presents an application of the model to a practical problem of train-induced vibrations. The aim of this study is to vertify for performance of isolators which was developed in KRRI supported floating slab track. Laboratory tests on developed isolations show that the energy dissipation, under cyclic loading of constant amplitude, can be suitably represented by a combination of a viscous and a hysteretic damping. Also, other tests for structural performance are carried out, such as elastic material test, compression test and so on. The specimen, $400{\times}400{\times}300mm$, is placed between two stiff steel plates designed to uniformly distribute the compression stress on the surface.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1242-1247
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• 2007

An active application of concrete track is being expected for the future constructions of Korea railroad. For the successful construction and design in embankment section, the roadbed behavior should be reasonably estimated using the proper analysis method. In this research, behaviors of reinforced roadbed constructed with the determined stiffness and thickness at embankment section were estimated through various design parameters and numerical analysis. A three dimensional finite element method was employed to determine the proper reinforced roadbed thickness at embankment section. The displacement and vertical stress caused by train loading were estimated and compared with the field test results. The bearing characteristics of concrete track roadbed were presented. Moreover, the method to determine thickness of reinforced roadbed was proposed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.281-285
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• 2008

The railroad roadbed plays an important role in distributing and transferring the train loading to subgrade, preventing subgrade from bearing softened by providing appropriate stiffness for subgrade, and eventually supporting the track structures. Presently, the reinforced roadbed was widely constructed in high speed line and is proceeding a research about economical thickness and methodologies for the design of reinforced roadbed. Field test section is located at Kyungbu line which is from Suwon to Cheonan In this study, field test were measured a track irregularity with several types of reinforced roadbed materials by using Track Master. The field testing were conducted between March, 2006 and April, 2008.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.350-358
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• 2009

To enhance the application of the reinforced retaining walls in the railway industry, this paper suggested a type of reinforcement subgrade with short reinforcement and rigid facing. To become popular the reinforced retaining walls in the industry, the deformation of retaining walls should be controlled below some limited level. In this paper, small scale and full scale tests of the proposed retaining walls were performed and their deformation characteristics were evaluated. Even though it has short reinforcement, the rigid type retaining wall had small deformation to the external train loading than the segmental type retaining wall had.

• 전기학회논문지
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• 제60권1호
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• pp.221-229
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• 2011

Recently, intermodal transportation systems are significantly considered as enhanced technique or future railroad logistics. These are aimed for particularly reducing complicated job process in the railroad based transportation and relevant logistic cost in economic viewpoint. In this paper we suggest a horizontal transfer system using hydro-motor and hydro-cylinder for intermodal transportation system. This system can assist to transfer the containers horizontally for train logistics automations.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.836-841
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• 2005

As gravel roadbed is gradually turn down by repetitive loading of train, lasting work for maintenance and management of track is necessary to reduce the settlement of roadbed and the deterioration of track. Despite of above weak point, gravel roadbed has become a basic structure of roadbed at the present time. But request for new structure of roadbed is recently presented to settle an increased transportation capacity of track, and to solve a shortage of the labor to handle maintenance work of track. Therefore, we begin to research about maintenance-free roadbed like paved track from two years ago. In this study, a series of tests were performed to clarify the characteristics of strength and permeability of concrete specimen, which is the upper part of paved track injected by cement mortar, by type of geotextile and finally to give a basic data for application of geotextile to the lower part of paved track.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.165-170
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• 2002

At the present time, civil structure based of aseismatic design in the Korea began about 1997. However, most of the railway bridge constructed with block and block in the past can easily deteriorate with time due to the increase of repeated traffic loading, increase of train speed, etc. In this study, soil properties of the substructure of railway bridge with block and block was investigated through the SASW(spectral Analysis or Surface Waves) and RCTC test in the field and laboratories. Also, stabilization of liquefaction after occurred earthquake was investigated through the Seed ＆ Idress method use of N value and Andrus and Stoke method use of S-Wave velocity.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.626-632
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• 2002

Geogrid is widely used as the reinforcement materials in railway earth structures in order to achieve efficient land utilization as well as securing safety in railway service lines in other countries. In this study, the real scale test was carried out to investigate the application of geogrid reinforced soil segmental retaining walls(SRWs) in railway. For this goal, the vibration transfer characteristics of reinforced soil segmental retaining walls was evaluated. The resonant frequencies of SRWs, vertical ground vibration in backfill and vertical/horizontal vibration at segmental units were acquired. This experimental data and analysis result can contribute to understand the vibration response behavior of SRWs.