• Proceedings of the KSR Conference
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• 2004.10a
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• pp.994-1000
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• 2004

It is growing the application of the removal ground anchor with tension force for earth retaining constructions in the downtown. Nowadays, we can find the compression dispersion anchor on many site. But, it is occur some probelems in behabior of anchors because of impossible to tense p.c strand uniformly with existing equipment due to different length of p.c strand. So we tried to tense each p.c strand uniformly with auto back equipment in-situ test. This study compared and analyzed in-situ test results of an existing equipment with those of auto back equipment by appling elastic theory. As a result of the test, It has been proved that differences of tension force in the existing equipment increases with increasing the number of p.c strands. This can cause the ultimate failure of the concentrated p.c strand and the shear failure of ground. So it has been proved that auto back equipment is necessary.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.756-762
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• 2004

Up to now, the only way is Floating Slab Track System, which cuts off vibration by installing spring between concrete slab and ground for the lines of particularly requiring attenuating vibration. The weak point of Floating Slab Track System is large increase of construction cost because normally the structure is getting bigger. In regards to this matter, Floating Rail Track System has been developed, which cuts off vibration by floating the first cause of vibration rail, and the system is in operation. In the thesis, the application of new attenuating vibration track system has been confirmed by studying theoretical background of Floating Rail Track System and evaluating dynamic deflection of track and attenuating of noise and vibration performance through various measurements from laboratory tests and site inspection.

• Proceedings of the KSR Conference
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• 2001.05a
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• pp.443-450
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• 2001

This paper shows the reduction effect of tile earthquake-induced liquefaction potential of soils that improved by Vibro-Replacement Stone Columns. The Vibro-Replacement Stone Columns method transforms soft cohesive soils into a composite mass of compacted granular or crushed stone columns by using vibrating equipment and water jets. This study investigated and analyzed the behavior of the stone columns and composite ground using the results of in situ test and measurement at the job-site. This paper shows the evaluation of the earthquake-induced liquefaction potential of soils using in situ test. There are different types of in situ test used in the evaluation the liquefaction potential. In the particular study the Standard penetration test, and Cone penetration test were used. The N value of Standard Penetration test has been used all over for a very long time. The evaluation of the liquefaction of soil was performed using the worldwide renewed Cone penetration test

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.82-90
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• 2003

The advance in technology of the CWR in Korea has led the establishment of the CWR on the sharp curve (i.e. less than R=600m). As thermit welding used in the sharp-curved construction site is carried out on the curve track, it is difficult to adjust a curve shape accurately and these difficulties have occurred in a number of cases. Therefore, in this study, the lateral buckling analysis of CWR track was carried out considering the actual ballast resistance force. In addition, the cant and vertical resistance force in ballast was considered in order to predict the initial behaviour of bucking in track under the more accurate method.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.443-447
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• 2005

When the high-speed train running on the track, there is a speed band which track distortion is unusually increased according to the condition of track and roadbed. This speed is called critical velocity and physical parameter value increased greatly. These phenomenon happened as high-speed train were developed, studied regularly through TGV 100 running test in France. As research result until now, the main reason is soft roadbed's capacity. Wave propagation and track support capacity is varied by the site characteristics. This paper achieved theoretical examination about resonance band(speed and frequency) that occurred in roadbed on the base rock in point of geotechnical engineering. The examination of resonance divides with ground response analysis, critical band analysis by the shear wave velocity of roadbed, train critical speed through the ground stratum.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.389-393
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• 2005

When the high-speed train running on the track, there is a speed limit which track distortion is unusually increased according to condition of track and roadbed. This speed limit is called critical velocity, and physical parameter value increased very greatly. These phenomenon happened as high-speed train were developed, studied regularly through TGV 100 running test in France. As research result until now, the main reason is soft roadbed's capacity. Wave propagation and track support capacity is varied by the site characteristics. This paper achieved theoretical examination about resonance band(speed and frequency) that occurred in roadbed on the base rock in point of geotechnical engineering. The examination of resonance divides with ground response analysis, critical band analysis by the shear wave velocity of roadbed, train critical speed through the ground stratum.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.389-394
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• 2003

Subway has been used one of major public transportations because of overpopulation and heavy traffic problems in the metropolitan areas. So, the air pollution has been serious. In this study, continuous date of PM-10 (particles with aerodynamic diameter < $10{\mu}m$) and heavy metal concentration measurements for winter, spring and summer. These measurements have been carried out in the outdoor, concourse, platform, tunnel. The study results showed that the average seasonally concentration of PM-10 particles were $141.57{\mu}g/m^3$ in winter. $129.34{\mu}g/m^3$ in spring and $122.73{\mu}g/m^3$. The average concentration of PM-l0 particles at indoor higher than outdoor. The concentration of Fe, Cu, showed the largest peak concentrations during the respective season.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.597-602
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• 2002

This study reviews several of the procedures that have been used to predict ground-born vibration. The vibration responses are measured at three sites that have different soil qualities. The measured vibration levels are compared with the predicted results by previously used vibration level prediction models. In this study a numerical method, which is based on explicit differential method, is used to compensate tot existing prediction models. Although numerically computed results are not quantitatively in good agreement with the measured results, the trends are comparable in the sense that vibration level does not decrease monotonically with distance. Also, The site with the deepest tunnel gives the highest vibration level.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.509-515
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• 2002

While performing the advisory services of the electrification of conventional lines for KTX(Korea High Speed Train), we faced the speed-up problem of catenary system for the existing narrow tunnel. To solve this problem, the new system, to be named "Oblique encumbrance tunnel catenary", was developed. This system is mainly characterized by a simple catenary type, a dual bracket, a oblique encumbrance, a small system height and the same bracket used for the radial tension load and compression one. In this paper, the basic concepts, overall system configuration and main points considered in a design phase for the ′oblique encumbrance tunnel catenary′ are described. Moreover, the detail design criteria and other contents like manufacturing pilot products and verifying the performance through a factory and site test are added.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.653-658
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• 2003

This study is represented a method to give connect to optical cable from accident site and reviewed the method to transmission a moving image to control centre by real time, following the study of image transmission method in copper cable section where is a main line of railroad communication. Concept of network is studied to use cable and equipment effectively, and it's also reviewed technology of digital image transmission system and image evaluation methods, in spite of the pixel of camera and monitor resolution determine quality of image when moving image transferring by point to point. In addition, this study is reviewed checks and considerations of image transmission equipment (codec) with various transmission methods in room test, and then examined and analyzed wire/wireless combined transmission methods at wayside.