• Tunnel and Underground Space
• /
• v.15 no.1 s.54
• /
• pp.61-70
• /
• 2005

The objective of this study was to analyze the smoke movement for the case of fire and to determine the interval between emergency exits in long tunnels. Based on Froude modeling, the 1/50 scaled model tunnel (20 m long) was constructed by acrylic tubes and tests were carried out systematically. From the strong relationship between CO propagation time and distance through the tunnel, it was found that the optimal escaping time was 6 minutes in case of 20MW fire. But, regarding passengers' psychological state under fire, another one minute of delay time should be considered. Therefore, the total escaping time should be estimated by 5 minutes. The interval between the emergency exits for vehicle passengers was calculated by 250 m with respect to the 5 minute of escaping time.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.12 no.1
• /
• pp.43-49
• /
• 2010

The escape connecting gallery in a tunnel on a road is one of emergency equipment to ensure safety for passer in the tunnel against the tunnel fire. Government stipulate over 500m tunnel has the cross passage at intervals of less then 250 m. However, this lump estimated interval is generated the concerns of exaggeration and under construction because peculiarity of the tunnel ex. The velocity of the tunnel airflow, an incline, degree of a fire, and innering area are not considered. The study indicate the way to estimate of the cross passage considered an incline and the velocity of the tunnel airflow for efficient application of cross passage on the tunnel design. As a result, in 0.0 m/s and 1.0 m/s of the velocity of the tunnel airflow case, the movement of smoke is influenced by the incline however, in 20 m/s case, it isn't influenced by incline much. According to the velocity of tunnel airflow and the incline, optimum interval of cross passage is not corresponded. Therefore established lump estimate that has 250 m intervals would be changed to estimate of optimum interval of cross passage that considered about the properties of tunnel, the velocity of the tunnel airflow, incline, degree of a fire and innering area of the tunnel.

• Magazine of korean Tunnelling and Underground Space Association
• /
• v.4 no.1
• /
• pp.40-49
• /
• 2002

• Magazine of the Korea Concrete Institute
• /
• v.24 no.1
• /
• pp.65-70
• /
• 2012

• Magazine of korean Tunnelling and Underground Space Association
• /
• v.13 no.6
• /
• pp.58-67
• /
• 2011

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.12 no.3
• /
• pp.201-213
• /
• 2010

Recently, plans of tunnel and construction have increased. Unfortunately, the more we have tunnels, the more we have accidents in there. Because an accident or a fire in the tunnel is fatal to user safety, social concerns are focusing on the disaster prevention facilities. Cross passage tunnel is regarded as one of the useful disaster prevention facilities, which is increasing, while there were only few studies about the support system. This study tried to verify whether the support system is appropriate or not with empirical methods-theoretical methods and back analysis using measurement data. Additionally, we also looked into the range of reinforcement in accordance with strength/stress ratio of rock mass.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.12 no.3
• /
• pp.247-255
• /
• 2010

Bonding strength of shotcrete is a significant influential factor which plays the role of collapse prevention of tunnel crown and of debonding prevention of shotcrete induced by the blasting vibration. Thus, the evaluation of the shotcrete bonding state is one of the core components for shotcrete quality control. In this study, the peak particle velocities induced by blasting were measured on the shotcrete in a tunnel construction site and its effect on the bonding state of shotcrete is investigated. Drilling and blasting technique was used for the excavation of intersection tunnel connecting the main tunnel with the service tunnel. Blast-induced vibrations were monitored at some points of the main tunnel and the service tunnel. The shotcrete bonding state was evaluated by using impact-echo test coupled with the time-frequency domain analysis which is called short-time Fourier transformation. Analysis results of blast-induced vibrations and the time-frequency domain impact-echo signals showed that the blasting condition applied to the excavation of intersection tunnel hardly affects on the tunnel shotcrete bonding state. The general blasting practice in Korea was evaluated to have a minor negative impact on shotcrete quality.