• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.474-479
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• 2008

The purpose of this paper is to estimate the fire safety in tunnels with bi-directional and/or congested unidirectional traffic where there may be people on both sides of the fire. Therefore, the spread and movement of smoke are simulated by Fire Dynamic Simulator code under different ventilation systems, longitudinal, semi-transverse, large port exhaust system. And as quantitative risk index, FED (Fractional Effective Dose) for each ventilation system are calculated and compared by existed code developed previous research.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.6
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• pp.561-571
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• 2014

The standards of ventilation system for bi-directional tunnel have not been established now. For this reason, with regard to the bi-directional tunnel below 1km, some problems have been appeared in ventilation capacity designing and in determining whether the mechanical ventilation system is needed or not for each case. In this study, we examine the characteristics of natural ventilations, analyze ongoing ventilation design cases for bi-directional tunnels and classify those cases into two groups. This study is carried out about the capability of using natural ventilating system by calculation of reasonable ventilation capacity in bi-directional tunnel and review of relationship between natural wind speed ($Vr^*$) and required speed(Vreq). This paper aims at providing a basis data for bi-directional tunnel ventilation design standards.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1238-1243
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• 2009

As Social Overhead Capital(SOC) has been expanded, the highway road construction has been accelerated and city road system has been more complicated. So, long road tunnels have been increased and traffic flow rate also has been raised. Accordingly, the exhausting gas of vehicle cars seriously deteriorates the tunnel inside air quality and driving view. In order to improve tunnel inside air quality, it is needed to introduce a compulsory ventilation system as well as natural ventilation mechanism. The former, that is, a special compulsory ventilation facility is very useful and helpful to prevent a tunnel of being contaminated by traffic in most case. In the case of obtaining clearer and longer driving view, the ventilation systems have to be considered in order to remove floating contaminants or exhaust gas from engines. In this paper, discharge electrode design technology will be discussed.

• Tunnel and Underground Space
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• v.11 no.4
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• pp.319-327
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• 2001

Introduction of new design tools has been required to optimally design and operate the ventilation system of long vehicle tunnels.. The demand has led to wide spread use of the simulation technique throughout the would to analysis the dynamic relationship among the variables associated with vehicle tunnel ventilation. This paper aims at performing on-site study at local tunnels to test the applicability of NETVEN, a simulation model vehicle tunnel ventilation. The study was carried out at four urban as well as highway tunnels model of vehicle tunnel ventilation. The study was carried out at four urban as well as highway tunnels employing different ventilation systems as well as traffic methods. There were some discrepancies sound between the simulation output and measurements and the following four factors are considered to mainly cause those disagreement. (1) The real situation shows distinctive transient and retarding characteristics with respect to air flow and contaminant dispersion, while ventilation forces are not steady-state and in particular those traffic and climatic variables show significant instantaneous variation. (3) Near the exit portal, the CO levels show bigger differences. The general trend is that data with higher CO concentrations carry bigger discrepancies. Turbulent diffusion is though to be the main reason for it and also contribute to the fact hat the highest CO concentrations are found at the locations somewhat inward, not at the exit portals. (4) Higher traffic rate results in higher discrepancies of ventilation velocity. Along with the exhaust characteristics, the vehicle aerodynamic characteristics need to be studied continuously in order to reduce the velocity disagreement.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.11
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• pp.1035-1043
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• 2004

For a long road tunnel, a tunnel ventilation system may be used in order to reduce the pollution level below the required level. To control the tunnel pollution level, a closed loop control algorithm may be used. The feedforward prediction algorithm and the cascade control algorithm were developed to regulate the CO level in a tunnel. The feedforward prediction algorithm composed of the traffic estimation algorithm and the CO density prediction algorithm, and the cascade control algorithm composed of the jet fan control algorithm and the air velocity setpoint algorithm. The verification of control algorithms was carried out by dynamic models developed from the actual tunnel data. The simulation results showed that control algorithms developed for this study were effective for the control of the tunnel ventilation system.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.3
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• pp.561-573
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• 2018

In order to design the ventilation in the road tunnel, it is necessary to know the ratio of average annual daily traffic by vehicle type. In general, the road tunnels are onedirectional tunnel, so the traffic of each vehicle type does not change along the tunnel. On the other hand, in the case of network road tunnels, since the connections in the tunnels are complex, the traffic of vehicle-type varies depending on the network composition of tunnels. In the studying the easy method for calculating the ratio of vehicle type for the network road tunnel are proposed with using incidence matrix.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.207-212
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• 2005

In designing a ventilation system of a road tunnel, a possibility of using the system as a smoke control system in case of a tunnel fire has to be considered. In the present study, a numerical simulation on ventilation system is performed considering jet fan operations and moving traffic. A fire-mode operation by reversing some fan operations in case of a tunnel fire is also simulated. The results show that ventilation operation can control the pollutants effectively, and fire-mode operation can control smoke and temperature effectively to prevent a disaster.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.E
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• pp.397-400
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• 1993

The possible air pollution problems in a proposed underground highway are discussed using carbon monoxide (CO) as an indicator. Carbon monoxide concentrations in the underground highway depend on several factors, including the size of tunnel, the number of automobiles, the CO emission rate, and the tunnel ventilation rate. Using the estimated values, CO concentrations in the underground highway can be predicted. Without proper ventilation system, CO concentration in the underground highway can be dangerous level. However, the cost of operating the mandatory mechanical ventilation system may be tremendouslyy high and may be technically unrealistic to implement. If the underground highway is constructed with proper ventilation system, a continuous air pollution monitoring system with alarming function must be installed to alert personnel of serious air pollution built up in the underground highway. Traffic must be restricted, whenever the inside air pollution levels exceed agreed values. Short distances between evacuation exits are necessary for emergency situations or malfunction of ventilation system.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.80-83
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• 2008

As SOC (Social Overhead Capital) has been expanded, the highway road construction has been accelerated and city road system has been more complicated. So, long road tunnels have been increased and traffic flow rate also has been raised. Accordingly, the exhausting gas of vehicle cars seriously deteriorates the tunnel inside air quality and driving view. In order to improve tunnel inside air quality, we may need to introduce a compulsory ventilation system as well as natural ventilation mechanism. The natural ventilation mechanism is enough for short tunnels, meanwhile longer tunnels require a specific compulsory ventilation facility. Many foreign countries already have been devoting on development of effective tunnel ventilation system and especially, some European nations and Japan have already applied their developed tunnel ventilation system for longer road tunnels. More recently, as the quality of life improved, our concerns about safety of driving and better driving environment have been increased. In order to obtain clearer and longer driving view, we are more interested in EP tunnel ventilation system in order to remove floating contaminants and automobile exhaust gas. Evan though it's been a long time since many European countries and Japan applied more economical and environment-friendly tunnel ventilation system with their self-developed Electrostatic Precipitator, we are still dependant on imported system from foreign nations. Therefore, we need to develop our unique technical know-how for optimum design tools through validity investigation and continuous possibility examination, eventually in order to localize the tunnel ventilation system technology. In this project, we will manufacture test-run products to examine the performance of system in order to develop main parts of tunnel ventilation system such as electrostatic precipitator, high voltage power generator, water treatment system, etc.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1302-1313
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• 2010

The west express way is notorious for extremely heavy traffic area in the west of Seoul, South Korea. Hence, the city government recently initiated a new underground BTO (Build-Transfer-Operate) road project to solve traffic congestion and a high construction cost. The proposed underground express road being designed is the first double-level tunnel ever designed in South Korea and using Conventional tunnelling method (NATM). A total length of tunnel for light vehicles is 10.91km long including both open cut structures and concrete lining with middle-deck in bored tunnel. There are also 4 ventilation shafts for ventilation and evacuation on emergency. Many design issues had been aroused during the preliminary design phase and detail design phase is currently going on. This paper discusses design focuses including excavation methods, ground water issues, a deck slab installation, and a construction cost etc. for the double level road tunnel design of urban area.