• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.5
• /
• pp.516-521
• /
• 2016

In this study, we investigated the operation of railroad fire fighting vehicles against fires on trains in a long railway tunnel. In recent years, long railway tunnels (more than 10 km in length) have been built and the number of such tunnels, such as the Geumjeong tunnel (20.3 km in length) on the Gyeongbu high speed line, Solan tunnel (16.7 km in length) on the Yeongdong line and Yulhyeon tunnel (50.3 km in length) on the Suseo high speed line which is scheduled to be opened in the second half of 2016, is increasing. Significant damage is to be expected, due to the increased evacuation time and limited accessibility of fire services when the train is stopped by an urgent fire in the tunnel. Special fire fighting vehicles capable of running on rails have been developed and operated in overseas advanced countries. Therefore, a fire-response system using Unimog vehicles, which can run on road and rail, instead of road vehicles, is necessary. The characteristics of the railway tunnel and thermal environmental change caused by a train fire in a tunnel were analyzed in this study. Also, the operational requirements of the railroad fire fighting vehicles were evaluated by taking into account the specifications of the railroad fire fighting vehicles under development.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.18 no.1
• /
• pp.41-52
• /
• 2016

When the queue length of congestion vehicles in tunnel fire is extended beyond tunnel length, the capacity of smoke control system needs to be increased in line with ventilation resistance. However, the vehicle queue length is not defined, so a rational equation is necessary in current fire prevention guideline. This study is intended to propose an equation to calculate the queue length considering the number of vehicles in queue in tunnel fire and evaluate the applicability by tunnel length as well. When it comes to normal tunnel, it is necessary to compare the vehicle queue length with tunnel length up to the length of 1,200 m in a bid to avoid applying the vehicle queue length excessively in case of fire. As a result of evaluation of applicability to model a tunnel, saving the number of jet fan for smoke control appeared to be effective. Besides, quantitative approach to explain the vehicle queue length through the relationship between the percentage of large vehicles and tunnel length was presented. Consequently, when the queue length of the congestion vehicles exceeds the tunnel length in determining the capacity of smoke control system in case of fire, the number of vehicles beyond the tunnel length needs to be excluded from estimating the ventilation resistance by vehicles.

• Fire Science and Engineering
• /
• v.30 no.2
• /
• pp.81-86
• /
• 2016

Recently, frequent traffic congestion has occurred in domestic urban roads. As a solution for downtown traffic congestion in domestic urban roads, plans for great depth underground double-deck tunnels have been made. Great depth underground double-deck tunnels that have been planned for passenger cars, has the structure of a network type; the entry of vehicles is carried out in the underground space. In these network great depth underground double-deck tunnels, the cross section and the height of the tunnel are smaller than the general road tunnel, and the smoke of a fire will propagate faster than the evacuation of tunnel passengers by the action of the traffic-ventilation and casualties are expected. Therefore, in the present study, an attempt was made to prevent the delay system for fire smoke diffusion at the time of a fire in a domestic network great depth underground double-deck tunnel according to the area of the tunnel block during the operation of the delay system for fire smoke diffusion to analyze the effects of reducing the inflow velocity. When the area of the tunnel block was not less than 50%, the effect of reducing about 21% of the wind speed acting on the tunnel was significant. If the area is more than 50%, the diffusion rate of fire smoke was reduced by approximately 21%, which will be useful for a safe evacuation.

• Fire Science and Engineering
• /
• v.20 no.2 s.62
• /
• pp.72-79
• /
• 2006

The objective of this study is to analyze the smoke extraction efficiency using by the partial extraction system with CFD simulation for case of tunnel fire. The Comparison of CFD results with the preceding scaled model test results, it is equal to the smoke extraction efficiency and smoke stratification in tunnel by the partial smoke extraction system (distributed damper). It shows that the smoke extraction efficiency is increased about 7% by the distributed damper which is opened near fire, compare with the distributed damper which is all opened. The case of the fire occurs on a traffic jam in a tunnel, it is proposed that the operating method of partial smoke extraction system for the escaping passengers.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.18 no.5
• /
• pp.413-418
• /
• 2016

Recently, a mega project such as Korea-China or Korea-Japan undersea tunnel project has been emerged for detail discussion and the interest in undersea tunnel is on the rise. More severe damage by train fire is expected in undersea tunnel comparing to ground tunnel and thus the study on more efficient fire extinguishing system, besides existing disaster prevention design is underway. To that end, a full-scale fire tests using CAF fire extinguishing system which has been developed by modifying traditional foam fire extinguishing system for fire suppression at rescue station in timely manner were conducted over 7 times. The test was conducted after setting the rescue station in virtual tunnel with a car of KTX. As a result of using compressed air foam directly to the fire source, 30 liter of Heptane combustibles was extinguished within 1 minutes. Applicability of compressed air foam to train fire at rescue station in undersea tunnel was has been proven and further study is considered required while changing the nozzle angle and location so as to achieve quick and easy extinguishing goal, making use of the advantage of CAF, as well as to reduce the fire water and chemicals required.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.20 no.4
• /
• pp.743-755
• /
• 2018

Tunnel is a semi-closed structure similar to underground space where the smoke generated from fire fills the space fast while escaping from the space slow. Because of such characteristics, when the fire breaks out by traffic accident, the vehicles are jammed making it difficult for the people to evacuate from the scene as well as for the fire engine to gain access to the scene. For such reasons, tunnels are globally categorized into some disaster classes for differentiated facilities and operation approaches. In Korea, less than a 1 km-long tunnel accounts for 80.0% and such a short tunnel which is categorized into Class III is not required to have smoke control system. In this study, a full-scale fire test was conducted in a bid to apply air curtain system using heat-resistant sirocco fan to a less than 1 km-long tunnel. To that end, heat resistance test to verify the normal operation at $250^{\circ}C$ for 60 minutes was conducted. Consequently, despite of rapid rising-temperature and increasing-carbon dioxide inside the air curtain (direction of fire in tunnel), initial condition was found to have been sustained outside the air curtain (opposite direction of fire in tunnel).

• Proceedings of the SAREK Conference
• /
• 2006.06a
• /
• pp.1209-1212
• /
• 2006

This study is aimed to analyze the floe patterns and thermal characteristics by computer simulation under the variations of fire strength for Daegu-Pahang Yimgo-4th tunnel, from which flow and heat distributions are predicted In the longitudinal tunnel. Though the results of numerical computations, followings are found; one is that the volume flow rate is discontinuously increasing as closer to fire location, and the other is that a critical design to get faster flow rate is required because of existence of backlayer flow for the high fire strength in view of safety for the people in fire of the tunnel.

• Fire Science and Engineering
• /
• v.31 no.6
• /
• pp.40-46
• /
• 2017

As one of the solutions to deal with economic loss caused by traffic congestion in metropolitan area, a deep underground road has been planned and implemented at home and abroad. The part of them has been pushed ahead with a double-deck scheme which has an advantage in constructability and cost efficiency comparing to traditional road tunnel. However, the double-deck tunnel has a lower floor height than the general road tunnel due to the special structure used as the upper and lower lines by installing the middle slab on one excavation section. Therefore, it is relatively weak against fire accidents and ventilation problems occurring in tunnels. Thus study to develop the life safety system optimized to a double-deck tunnel has been systematically carried out in order to overcome their weak point. In this study, automatic monitoring fire extinguisher (AMFE) is developed to suppress a fire and prevent its spread at early stage of tunnel fire, conducting the performance test through vehicle fire tests as verification. The tests were conducted with AMFE being 30 m apart from the vehicle and 10 m apart from engine room. As a results, it was confirmed that AMFE enables to suppress a fire and prevent its spread in both cases.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.6 no.2
• /
• pp.129-139
• /
• 2004

The several assumptions and design parameters to determine the ventilation rate in tunnel ventilation system were examined. In longitudinal ventilating tunnel, the ventilation rate has been determined by the critical velocity above which the smoke propagation to the upstream of ventilating air is prevented. Based upon the examination of assumptions and experimental results, we suggested the improved method to determine the critical velocity. In transverse ventilating tunnel, we found that the ventilation rate has been determined in accordance with the custom rather than fire-smoke dynamics such as the critical velocity in the longitudinal ventilating tunnel. It is because the ventilation rate in the transverse ventilation system has been determined by considering only the ventilation of contaminant by vehicle. To improve the ventilation design parameters based upon the fire-smoke dynamics, we conducted model tunnel fire experiments. From the experimental results, smoke propagating distance and smoke filling were suggested as the design parameter to determine the ventilation rate in transverse ventilating tunnel. And tunnels in Europe designed by the custom is found to have the dangerous nature in view of fire safety.

• Journal of Korean Society of societal Security
• /
• v.2 no.1
• /
• pp.57-64
• /
• 2009

With the increase in construction of long railway tunnel, social interest in the railway tunnel fire risk has also increased. However, quantitative fire risk research on this topic is still lacking, especially in terms of consideration of uncertainty of each variables used in risk analysis. Hence, in this study, to improve the overall performance of fire risk analysis technique for railway tunnel, Monte-Carlo simulation method is added to the traditional probabilistic risk analysis based on event tree approach and its validity is investigated by applying it to the real railway tunnel project.