• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1641-1646
• /
• 2007

Subway station is installed with equipment of deficient ventilation and air purification in need of routine activity for users because projectors didn't have recognition of the importance of prevention equipment on disasters in subway stations. So if the accident in Deagu is occurred again, we can't prevent it. And it is urgently necessary to improve antique subway station for the safety and service to citizens because users were increased far more. Improvement of subway station has to be modernized the backward and antique subway station and maintained and developed by the center of traffic to give the social contribution with management of social facilities. And subway station has to be made conveniently so that everyone may use the station with one-stop system including sales, business, service equipment. This study will show the improvement plan of problem in underground space and situation of metropolitan-train history to improve metropolitan-train station .we will study a traffic line and equipment relocation of underground space considering safety by choosing the improved station and problems of the underground station in seoul. And then we will study the improvement plan of air purification and sound isolation to upgrade service in citizens.

• 한국전산유체공학회:학술대회논문집
• /
• 2007.04a
• /
• pp.64-67
• /
• 2007

In the present study, the wind pressure transients on platform screen door in side platforms caused by passing trains have been investigated numerically. The transient compressible 3-D full Navier-Stokes solution is obtained with actual operational condition of subway train and the moving mesh technique is adopted considering the train movement. To achieve more accurate analysis, the entrance and exit tunnel of platform are included in a computational domain and detailed shape of train is also modeled Numerical analyses were conducted on five operational condition which are different velocity variation of subway train, existence of stationary train and passing each other trains. The results show that pressure load on platform screen door is maximized when the two trains are passing each other. It is also seen from the computational results that the maximum pressure variation was found to be satisfactory to various foreign standards.

• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.446-454
• /
• 2011

The noise of the subway has become a social issue and includes very complex reasons. The friction between rail and train wheel is the most important reason of the noise. In this study, we developed MFI(Multi Fluid Injection) System which sprays the mixed fluid(water, anticorrosive and lubricant) on the rail when the train is approaching to reduce the friction. To verify the system's effect, we measured the internal and external noise of the running train. The measured and analyzed results show that MFI system reduce the noise of the running subway.

• Proceedings of the KSR Conference
• /
• 2005.11a
• /
• pp.976-981
• /
• 2005

The Seoul subway line No.2 is the one of the busiest metro service line of the passenger transportation in Seoul metropolitan city. The number of the passengers served by the Seoul subway line No.2 is more than 1.9 million in a day according to the transportation reference of 2004, which is about $15\%$ of the whole population in Seoul metropolitan city. This is the reason why the Seoul Metropolitan Subway Corporation(SMSC) is implementing the refurbishment of the current ATS signalling system of Seoul Line No.2 into the most advanced ATO system with the continuous air-gap telegram transmission through the track circuit without any suspension of the train service either in when or in where, which is the first in the world in its attempt to refurbish the old signalling system under service without any suspension of the train operation.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.3 no.3
• /
• pp.195-202
• /
• 1999

This study present the stability of middle slabs directly supporting train loads in the subway station. According to results of Quality confirmation, mixing and curing conditions are good. But, when effects of hydration heat are analyzed, cracks seems to take place because tensile stress is higher than tensile strength in several points of middle slabs. It is found that vibration by train running don't have an effect on cracks in the structure. The structural analysis shows that there is no problem on the stability of structural body, but the design through 3-dimensional analysis is need to consider columns and opening specially in the subway station structures.

• Journal of KSNVE
• /
• v.11 no.2
• /
• pp.249-256
• /
• 2001

In this paper the characteristics of vibration induced by subway trains running on track is discussed. The quantitative prediction of the vibration level and the countermeasure for reduction of necessary, is of importance for the better environment. It was made the constructed Bundang line as first step with the modified Young-Dan type to basis on the Japanese Young-Dan type. In this paper it was measured and analyzed to two region ($ \circled1$Susuh-Bokjung. $ \circled2$Chorim-Suhyun region) of this. at present, operational Bundang line when averaging velocity of train is 60 (km/h). As the response characteristics of frequency Induced by subway operation, it was confirmed that frequency band of neighborhood of 30~80 Hz in generally dominant. Also to assess the quantitative nitration as response level to be measured for each point of two region in subway operation, the vibrational response level was measured at the state to be not subway operation. And the level was approximately $\fraction one-fifth~\fraction one-ten$ level comparing to subway operation.

• Structural Engineering and Mechanics
• /
• v.71 no.2
• /
• pp.131-138
• /
• 2019

It is necessary to predict subway induced vibration if a new subway is to be built. To obtain the vibration response reliably, a three-dimensional (3D) FEM model, consisting of the tunnel, the soil, the subway load and the building above, is established in MIDAS GTS NX. For this study, it is a six-story frame structure built above line 3 of Guangzhou metro. The entire modeling process is described in detail, including the simplification of the carriage load and the determination of model parameters. Vibration measurements have been performed on the site of the building and the model is verified with the collected data. The predicted and measured vibration response are used together to assess vibration level due to the subway traffic in the building. The No.1 building can meet work and residence comfort requirement. This study demonstrates the applicability of the numerical train-tunnel-soil-structure model for the serviceability assessment of subway induced vibration and aims to provide practical references for engineering applications.

• Journal of Korean Society for Atmospheric Environment
• /
• v.24 no.2
• /
• pp.153-161
• /
• 2008

The guidelines for indoor air quality of public transportations such as subway, train and bus was presented by Korean Ministry of Environment last end of year 2006 based on the great consequence of indoor air quality in daily life. Two main parameters, carbon dioxide($CO_2$) and particulate matters smaller than $10\;{\mu}m(PM_{10})$, were selected as index pollutants for the management of indoor air quality. The former pollutant, $CO_2$, is regarded as index of ventilation status and the major source of $CO_2$ in the train or subway is the exhalation of passengers. It is publically perceived that the high $CO_2$ concentration in a crowded subway will be reduced and ventilated with outdoor air by door-opening taken every 2 or 3 minutes when the train stops each station. However, there has not been any scientific proof and quantitative information on the effect of door-opening on the $CO_2$ reduction by ventilation with outdoor air. In this study, $CO_2$ concentration and number of passengers were measured at each station on the 3 lines of Korail metropolitan subway. In order to evaluate the effect of $CO_2$ reduction by door opening, the theoretical approach using the $CO_2$ balance equation was performed. By comparing the predicted data with monitoring one, the optimum $CO_2$ dilution factor was determined. For the first time, it was quantified that about 35% of $CO_2$ concentration in the subway indoor was removed by the door-opening at each station.

• Smart Structures and Systems
• /
• v.19 no.1
• /
• pp.1-10
• /
• 2017

The operation of subway trains induces secondary structure-borne vibrations in the nearby underground spaces. The vibration, along with the associated noise, can cause annoyance and adverse physical, physiological, and psychological effects on humans in dense urban environments. Traditional tethered instruments restrict the rapid measurement and assessment on such vibration effect. This paper presents a novel approach for Wireless Smart Sensor (WSS)-based autonomous evaluation system for the subway train-induced vibrations. The system was implemented on a MEMSIC's Imote2 platform, using a SHM-H high-sensitivity accelerometer board stacked on top. A new embedded application VibrationLevelCalculation, which determines the International Organization for Standardization defined weighted acceleration level, was added into the Illinois Structural Health Monitoring Project Service Toolsuite. The system was verified in a large underground space, where a nearby subway station is a good source of ground excitation caused by the running subway trains. Using an on-board processor, each sensor calculated the distribution of vibration levels within the testing zone, and sent the distribution of vibration level by radio to display it on the central server. Also, the raw time-histories and frequency spectrum were retrieved from the WSS leaf nodes. Subsequently, spectral vibration levels in the one-third octave band, characterizing the vibrating influence of different frequency components on human bodies, was also calculated from each sensor node. Experimental validation demonstrates that the proposed system is efficient for autonomously evaluating the subway train-induced ambient vibration of underground spaces, and the system holds the potential of greatly reducing the laboring of dynamic field testing.

• Proceedings of the KIEE Conference
• /
• 2002.11d
• /
• pp.330-333
• /
• 2002

Even if the train of subway starts in a certain interval from the origin according to the operation plan. as the number of passenger gets increased during operation. the boarding and getting-off time will increase, and the temporary breakdown happens to the system of train during operation, causing the delay from the operation plan. this leads to the vicious circle of train operation. making the interval of train operation irregular in downtown especially. To solve this problem, we propose the method of advanced algorithm by the actual data relating to the train operation including operation time required between stations, distance between stations. capability of train, and the dwelling time, location and distance between the preceding train and next one. The central train control system adjusts the dwelling time at each station in order to recover the delayed time, and increase the operation speed at the each station. As control algorithm is applied the dwelling time and to increase the speed, the train maintains certain interval after certain amount of time passes.