• Journal of the Korean Society for Railway
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• v.20 no.5
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• pp.668-682
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• 2017

Alignments of railways recently constructed in Korea have been straightened due to the advent of high-speed rail, which means increasing the numbers of tunnels and bridges. Overbreak during tunnel construction may be unavoidable, and is very influential on overall stability. Over-excavation in tunneling is also one of the most important factors in construction costs. Overbreak problems around crown areas have decreased with improvements of excavation methods, but overbreak problems around bottom areas have not decreased because those areas are not very influential on tunnel stability compared with crown areas. The filling costs of 10 cm thickness of overbreak at the bottom of a tunnel are covered under construction costs by Korea Railway Authority regulations, but filling costs for more than the covered thickness are considered losses of construction cost. The filling material for overbreak bottoms of tunnels should be concrete, but concrete and mixed granular materials with fractured rock are also used for some sites. Tunnels in which granular materials with fractured rock are used may have a discontinuous section under the concrete slab track. The discontinuous section influences the propagation of waves generated from train operation. When the bottom of a tunnel is filled with only concrete material, the bottom of the tunnel can be considered as a continuous section, in which the waves generated from a train may propagate without reflection waves. However, a discontinuous section filled with mixed granular materials may reflect waves, which can cause resonance of vibration. The filled materials and vibration propagation characteristics are studied in this research. Tunnel bottom filling materials that have ratios of granular material to concrete of 5.0 %, 11.5 %, and 18.0 % are investigated. Samples were made and tested to determine their material properties. Static numerical analyses were performed using the FEM program under train operation load; test results were found to satisfy the stability requirements. However, dynamic analysis results show that some mixed ratios may generate resonance vibration from train operation at certain speeds.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.5
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• pp.809-822
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• 2018

A quantitative risk assessment has been introduced to quantitatively evaluate fire risk as a means of performance based fire protection design in the design of railway tunnel disaster prevention facilities. However, there are insufficient studies to examine the effect of various risk factors on the risk. Therefore, in this study, the risk assessment was conducted on the model tunnel in order to examine the effects of the evacuation start time delay and the fire growth curve on the quantitative risk assessment. As a result of the analysis of the scenario, the fatalities occurred mainly when escapes in the same direction as the direction of the fire smoke movement. In addition, after the FED exceeded 0.3, the maximum fatalities occurred within 10 minutes. In the range of relatively low risk, distance between cross passages, evacuation delay time and fire growth curve were found to affect the risk, but they were found to have little effect on the condition that the risk reached the limit. Especially, in this study, it was evaluated that the evacuation delay time reduction, fire intensity and duration reduction effect were not observed when the distance between cross passages was more than 1500 m.

• Journal of Digital Convergence
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• v.19 no.9
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• pp.9-18
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• 2021

Constructing the Metropolitan Railway Express (the GTX) may have an impact on consumer confidence and housing sales price located near the planned route. This study looked at how consumers' psychology and housing prices change as the large-scale transport infrastructure plane was planned. Also, it looked at the relationship between consumer sentiment and housing prices to analyze the impact of new transportation facilities inflows. Using a correlation analysis, the relationship between the consumer sentiment index and the actual transaction price of apartments was identified. The impact of GTX on the consumer sentiment index and the actual transaction price of apartments was looked at using the Difference-in-Differences methodology. Our finding shows that the construction plan of a large-scale transportation infrastructure in the metropolitan area affects the sentiment of housing consumption and actual transactions. In a situation where the government is speeding up the construction of a wide-area transportation network such as GTX with the goal of becoming a city where people can commute to downtown Seoul within 30 minutes, policies that can stabilize the housing market in transportation hubs should be suggested.

• The Journal of the Korea Contents Association
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• v.18 no.12
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• pp.456-467
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• 2018

This study analyzed the repeated causes of policy failure focusing on Yangyang International Airport cases. Yangyang International Airport, which opened in 2002, was built with about 360 billion won, but it is considered as a representative example of policy failure of local airports. According to the policy failure theory, the failure factors of Yangyang International Airport are anlyzed by rationalistic, political, and environmental complexity viewpoint. The results are as follows. First, from a rationalist point of view, Yangyang Airport failed to achieve the policy goal of securing passengers and revitalizing local economy, This is due to the pressure of politics and the lack of geographical infrastructure. Second, the failure of the stakeholders to resolve conflicts in the flow of politics can be seen as the conflict between the airline and the airport, and the failure to reconcile conflicts between the government and the airports on the low cost airline permits and subsidies. Third, from the viewpoint of environmental complexity, Yangyang International Airport can be regarded as a failure to adapt to environmental changes such as the opening of nearby expressways and railway lines, and the sharp decline of Chinese tourists. This study sugeests the establishment of an independent organization that can prevent unreasonable business promotion by politics in the case of large scale national projects, the linkage with the surrounding infrastructure and related businesses in the case of transportation facilities such as airports and railways, and institutionalization of cooperative governance for coordinating conflict among stakeholders.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.6
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• pp.793-799
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• 2023

This study classifies the types of urban railway stations that reflect the location characteristics of urban railway stations, the structure and form of station taxes, and the number of users, and the level of inconvenience in the transfer movement line for users by station type, the number and connectivity of transfer information, and the level of transfer convenience facilities. The number of installations, conflicts between users, and transfer information signs were analyzed. As a result of data analysis, it was found that the factors that cause the most inconvenience to urban rail users when transferring are the length and curvature of the transfer line, pedestrian density and number of passengers in the transfer passage, presence or absence of transportation convenience facilities, and the size and height of transfer information letters. These transfer inconveniences were objectified, quantified, and presented as evaluation indicators that can measure the transfer convenience of urban railway stations. Additionally, an evaluation scale was developed to measure the service level for each evaluation indicator. The evaluation scale for each indicator presented six levels by applying linear interpolation based on the maximum and minimum values of data derived through field surveys. However, it is judged that a comprehensive evaluation of transfer convenience that combines the importance and weight of each convenience evaluation indicator should be established through future research.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1872-1885
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• 2011

In recent years, due to the economic growth of the Northeast Asia, the trading relationship among the Asian countries becomes more active, and the mutual level of dependence is increasing. As the general market, the Northeast Asia pursue a function of market and economic activities among the Northeast Asia become more active consistently. It is important that Korea strengthened logistics network connection systems with China and Japan are improving the logistics facilities and expanding the transport network steadily. In order for Korea to improve as a logistics position, Korea needs to build various and efficient multimodal transport system and sets up a position as a major efficient logistics network center. Therefore, this paper intended to analyze transport cost and time of Korea-China-Japan logistics network and suggest a competitive multimodal transport with the maritime transport and new multimodal transport systems by comparing scenarios.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.3
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• pp.239-247
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• 2005

A new railway line of about 17km length was planned between Dongbaeksan and the neighboring town Dokye to improve the existing decrepit railway system. New line about 17km of the distance will almost be in circular alignment tunnels owing to the difference of elevation about 380m. Since the geology of the area is rather unusual compared to the normal in South Korea, extensive geological investigations have been carried out to prepare geological maps and profiles along the planned tunnel routes. The tunnel will almost be in sedimentary rock formations, such as limestone, sandstone, shale, coal etc and be near abandoned mines Various rock formations have the complicated, alter ed those rocks, but are well developed with laminated formations. Each rock formations have been classified using the Q-system and the cost of tunnel excavation, support has been estimated and compared for three alternative routes in the design stage. Based on these estimates, the final route of t he railway line was chosen.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.779-785
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• 2007

This study identifies visible/invisible factors and analyzes facilities, structure, and visible perceptive contents in the aspects of operation and efficiency with a focus on the interfaces between interior design of the subway and users. More specifically, it diagnoses the requirements and empirically presents improvements. As the interior design in the subway trains is fur the public reflecting the value, consciousness, and behaviors of users, it should be approached through the application of the concept of universal design that considers the potential needs and psychological satisfaction of users. In arranging the indoor of the vehicles, the conditions for the facilities should be specified through the interdisciplinary approach from professional fields including ergonomics and psychology, the path of flow should be induced through the use of space and the analysis of passengers' behaviors, an integrated planning should be re-established, and continuous evaluations of basic guidelines, manuals, and requirements should be made.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.187-196
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• 2014

In this paper, Minimize driving energy for operation within a defined distance yeokgan fixed time-resolved and determine the nature of the train is traveling, and to model mathematically. Urban rail car cruise in general by the PID controller is used instead of automatically tracking a target value while traveling in energy consumption to be minimized by using optimal control model railroad charyangreul was designed under real operating conditions the same. The actual track conditions apply to the minimum value or a separate listing of cars around the track facility without a driving energy of the automatic operation and to reduce the driving energy. Therefore, actual route chosen straight line 8 / gradient segment / curve for the measured data analysis, such as sections within the city-minute drive each section and presented how the trains to save energy, depending on the pattern of the train station in the region.

• Current Research on Agriculture and Life Sciences
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• v.31 no.4
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• pp.256-264
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• 2013

This study presents a greening plan for the under space of elevated rail tracks to reducing landscape impairment and improve the streetscape. This study focuses on a section of the Daegu Metro line number 3 that includes a concentration of high-rise apartments and commercial areas. First, different types of planting were categorized for the under space of the elevated rail track, and then images of each planting type were created using a 3D simulation tool to evaluate the visual characteristics. The landscape images and related adjectives were assessed using a survey. As a result, rows of flower trees received the highest evaluation, and 'harmony' was identified as the most important factor affecting the railscape preference. These results can be important data for establishing an efficient greening plan for the under space of elevated rail tracks.