• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1287-1296
• /
• 2007

Recently, the high speed railway comes into the spotlight as the important and convenient traffic infrastructure. In Korea, Kyung-Bu high speed train service began in about 400km section at 2004, and the Ho-Nam high speed railway will be constructed by 2017. The high speed train will run with a design maximum speed of 300-350km/hr. Since the trains are operated at high speed, the differential settlement of subgrade under the rail is able to cause a fatal disaster. Therefore, the differential settlement of the embankment must be controlled with the greatest care. Furthermore, the characteristics and causes of settlements which occurred under construction and post-construction should be investigated. A considerable number of studies have been conducted on the settlement of the natural ground over the past several decades. But little attention has been given to the compression settlement of the embankment. The long-term settlement of compacted fills embankments is greatly influenced by the post-construction wetting. This is called 'hydro collapse' or 'wetting collapse'. In spite of little study for this wetting collapse problem, it has been recognized that the compressibility of compacted sands, gravels and rockfills exhibit low compressibility at low pressures, but there can be significant compression at high pressures due to grain crushing by several researchers(Marachi et al. 1969, Nobari and Duncan 1972, Noorany et al. 1994, Houston et al. 1993, Wu 2004). The characteristics of compression of fill materials depend on a number of factors such as soil/rock type, as-compacted moisture, density, stress level and wetting condition. Because of the complexity of these factors, it is not easy to predict quantitatively the amount of compression without extensive tests. Therefore, in this research I carried out the wetting collapse tests, with focusing in various soil/rock type, stress levels, wetting condition more closely.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.3
• /
• pp.1279-1287
• /
• 2014

The Korean government establishes a strategy to develop the Busan New Port as a world ranking two transit-oriented port. This paper aims at presenting an efficient inter-terminal transport (ITT) system in the Busan New Port as a method of achieving the government strategy. First, it presents results of long term forecast for the inter-terminal transportation volume in the port. Second, it proposes two systems to treat ITT in the port; Double stack Multiple Trailer System (DMTS) and Rail-based transportation system. The implementation methods in the port are introduced in detail for the both systems, and the required number of the systems and costs are calculated for implementation of both the systems. B/C for DMTS is analyzed to 3.7, moreover unit-fare per [$ton{\cdot}km$] can is lowered to 67% against current fare. DMTS is shown to highly potential for efficient ITT in the port.

• International Journal of Highway Engineering
• /
• v.15 no.4
• /
• pp.127-133
• /
• 2013

PURPOSES : The impact performance of flexible barrier system such as structural response, vehicular motion and occupant safety vary depending on the impact point. Thus, to properly evaluate the performance of a flexible barrier system, impact should be made to a point which will lead to the worst possible results. This point is called the Critical Impact Point (CIP). This paper presents the way to determine the CIP for a SB2 class flexible barrier system which is consisted of Thrie-Beam rail and circular hollow tube post of 2m span. METHODS: Barrier VII simulations were made for impact points; Case 1 at a post, Case 2 at 1/3 span downstream from a post, Case 3 at middle of the span, Case 4 at 2/3 span downstream from a post. For the structural performance (deflections), impact simulation of 8000kg-65km/h-15degree was used, and for vehicle motion and occupant safety, simulation of 1300kg-80km/h-20degree impact was made and analysed. RESULTS: Case 1 gave the largest dynamic deflection of 75.72cm and also gave the largest snag value of 44.3cm. Occupant safety and exit angle of the vehicle after the impact were not sensitive to the impact point and were all below the allowable limit. CONCLUSIONS : For the SB2 class flexible barrier system's CIP can be regarded as a post which is sufficiently away from the end of Length of Need in order to avoid the end-effect of the barrier system. It can be more economic in the long run because the normal concrete pavement material is likely to cost more due to higher probability of maintenance and repair and higher social cost due to traffic accident, etc.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.1003-1009
• /
• 2009

The Spatial Image contents of Geomorphology 3-D environment is focused by the requirement and importance in the fields such as, national land development plan, telecommunication facility management, railway construction, general construction engineering, Ubiquitous city development, safety and disaster prevention engineering. The currently used DEM system using contour lines, which embodies geographic information based on the 2-D digital maps and facility information has limitation in implementation in reproducing the 3-D spatial city. Moreover, this method often neglects the altitude of the rail way infrastructure which has narrow width and long length. This As the results, We confirmed the solutions of varieties application for railway facilities management using 3-D spatial image contents and database design. Also, I suggested that U-city using railway modeling about matching methods of high density elevation value using 3-D aerial photo with laser data are best approach for detail stereo modeling and simulation.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.2303-2315
• /
• 2008

Finally, Musan-Bongdong section in Kyeong-Ui corridor opened on 11. DEC.2007, which is a historical event, because this connection means the restoration of 56 yrs' disconnection since 1951 and also starting point launching to connect china, Mongolia, Russia for continental railway logistic infrastructure. This is also one of master plans about the northern line in TAR, carried out by UNESCAP, so this study will touch up each country's railway status and the next tasks related with trans-continental railway such as North Korea, Russia, China. Also, this study reveal a mid-long term development strategy to improve the North Korea railroad for a continent rail link and international railroad transportation between China and Russia, and also checks the way of confrontation to the domestic infrastructure for the activation of the continent railway and the north and south, investigates concretely how to establish TAR northern part routes as soon as possible.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.32 no.4
• /
• pp.105-117
• /
• 2004

The Pasadena Freeway follows the Arroyo Seco through foothills and scenic passes to link Downtown Los Angeles with Pasadena. The approximately 10 mile road was the first freeway built in the West during the 1930's and is today designated as a Historic Parkway. As it approaches Pasadena, it terminates at a traffic light intersection at Glenarm Street, and then becomes a commercial road the Arroyo Parkway. This one and a quarter mile long, north south road moves significant volumes of traffic both into and out of Pasadena. The Arroyo Parkway is thus a major 'gateway' and an important axis of orientation and movement, terminating in the City's core civic, commercial and retail district. Planting, lighting, signage, paving, furnishing and fixtures ought to all be properly designed and coordinated to create a distinctive 'gateway' experience arriving to Pasadena and driving along the Arroyo Parkway. Alternate design studies, developed in discussion with City officials and others involved in the redevelopment of the area, would need to be done to properly decide on the best direction. Issues of heritage and traditional streetscape will likely have to be reconciled with both the reality of the vehicular character of the road and more contemporary themes. Obviously with such large parcels of property available in the Arroyo Fair Oaks corridor, there is a huge potential for redevelopment and building. This potential would only be strengthened by the Light Rail Line and its stations, the improvements to the Arroyo Parkway, and the redevelopment of the Arts Center College of Design. Guides and controls to the development process, including programming and physical design studies, would need to be developed in order to ensure that the maximum potential for the corridor be realized. This concept proposal suggests that the whole strip might be developed as a Arts and Technology corridor, with special emphases on education, public culture, media and lifestyle. The full programming possibilities need to be further developed. Additionally, appropriate urban design guidelines to ensure high quality development also need to be incorporated into an overall development plan.

• Structural Engineering and Mechanics
• /
• v.66 no.1
• /
• pp.15-25
• /
• 2018

Post-construction subgrade settlement especially differential settlement, has become a key issue in construction and operation of non-ballasted track on high-speed railway soil subgrade, which may also affect the dynamic performance of passing trains. To estimate the effect of differential subgrade settlement on the mechanical behaviors of the vehicle-slab track system, a detailed model considering nonlinear subgrade support and initial track state due to track self-weight is developed. Accordingly, analysis aiming at a typical high-speed vehicle coupled with a deteriorated slab track owing to differential subgrade settlement is carried out, in terms of two aspects: (i) determination of an initial mapping relationship between subgrade settlement and track deflections as well as contact state between track and subgrade based on a semi-analytical method; (ii) simulation of dynamic performance of the coupled system by employing a time integration approach. The investigation indicates that subgrade settlement results in additional track irregularity, and locally, the contact between the concrete track and the soil subgrade is prone to failure. Moreover, wheel-rail interaction is significantly exacerbated by the track degradation and abnormal responses occur as a result of the unsupported areas. Distributions of interlaminar contact forces in track system vary dramatically due to the combined effect of track deterioration and dynamic load. These may not only intensify the dynamic responses of the coupled system, but also have impacts on the long-term behavior of the track components.

• Journal of the Korean Society for Railway
• /
• v.20 no.5
• /
• pp.612-624
• /
• 2017

As the existing metropolitan area metropolitan railway operates on a one-to-one basis, which leads to long travel times, its competitiveness with other means of transportation is deteriorating. Since there is a limit to attracting road traffic by rail, there is a continuing societal demand to expand express train service. Especially in the northern and the southwestern parts of the metropolitan area, a public transportation network system with express function, connecting to the city center of Seoul, is needed because of the social cost of the increase of traffic congestion and the increase of the travel time. The most efficient express service in Korea is Seoul Subway Line 9, which runs in 27 minutes from Gimpo Airport to the high speed terminal; this is a 40% shorter time compared to 44 minutes by car; the congestion in this area is up to 240%, so the preference for this train is quite high. The technical results of this study are expected to contribute to the implementation of an express service metropolitan railway.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.17 no.5
• /
• pp.45-51
• /
• 2018

Roll forming refers to the production of long plate-molded products, such as panels, pipes, tubes, channels, and frames, by continuously causing the bending deformation to thin plates using rotating rolls. As the roll forming method has advantages in terms of mass production because of its excellent productivity, the size of the roll forming industry has been continuously increasing and the roll forming method is increasingly being used in diverse industrial fields as a very important processing method. Furthermore, as the roll forming method mainly depends on the continuous bending deformation of the plate materials, the time and the cost of the heterogeneous materials developed in the process are relatively large when considered from the viewpoint of plastic working because many processes are continuously implemented. The existing studies on roll forming manufacturing have reported the loss of large amounts of time and materials when the raw materials or product types were changed; further, they have stated that the use of this method can hardly guarantee the uniformity of the formed shapes and the consistency in terms of size and cannot detect all the defects occurring during the mass production and related to the dimensions. Therefore, in this research, a real-time process data-based smart roll forming method that can be applied to multiple products was studied. As a result, a roll forming system was implemented that remembers and automatically sets the changes in the finely adjusted values of the supplied quantities of individual heterogeneous materials so that the equipment setting changing time for heterogeneous material replacements or changes in the products being produced can be shortened. It also secures the uniformity of the products so that more competitive and precise slide-rail products can be mass-produced with improvements in the quality, price, and productivity of the products.

• Journal of the Korean Geotechnical Society
• /
• v.24 no.11
• /
• pp.25-34
• /
• 2008

An application of concrete track is being actively processed for the construction of Korean high speed railway. The concrete track has an advantage in decreasing the maintenance cost, whereas it has much difficulty controlling the long term settlement after settlement occurred. Therefore, the management and control of settlement are very important for the successful construction of concrete track. The purpose of this paper is to verify the allowable settlement between concrete track and ballast track, and piled raft foundation installation effects as settlement reducers for concrete track. Therefore, a series of 3D finite element analyses that take into account the allowable settlement were performed for major parameters such as soil condition, pile installation and loading type. Based on the analysis, it is shown that concrete track causes much smaller settlement than ballast track, and the effect of installation is necessary to effectively reduce the settlement of concrete track.