• Journal of Korean Tunnelling and Underground Space Association
• /
• v.6 no.2
• /
• pp.151-160
• /
• 2004

This study has carried out a series of field investigation for a ASSM railway tunnel which was constructed several decades ago. It appears that the tunnel lining was cracked in the region of arching structure. Precise inspection is carried out for this region with various non-destructive testing equipments. Based on the inspection results, the cause and the effect of tunnel defects were discussed by conducting the evaluation of tunnel safety with numerical analysis.

• Proceedings of the KSME Conference
• /
• 2000.04b
• /
• pp.619-624
• /
• 2000

The purpose of present study is to investigate for reducing micro pressure waves generated according to train speeds $(240km/h{\sim}380km/h)$ through tunnels with countermeasures as followings; the hood configuration in tunnel entrance. We developed hoods for tunnel of 0.5 km length in the condition of tunnel cross-section area of $107m^2$ on the slab track. According to the results the maximum micro-pressure wave is reduced by 41.2% for the slit hood installed at the entrance of the tunnel and reduced by 47.7% for the slit hood installed at the entrance of the tunnel and the $45^{\circ}$ slanted portal at the exit of the tunnel

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.115-120
• /
• 2003

In this study, smoke movement in tunnel fires was investigated with various aspect ratio(0.5, 0.667, 1.0, 1.5, 2.0) of tunnel cross section. Reduced-scale experiments were carried out under the Froude scaling using 8.27 kW ethanol pool fire. Temperatures were measured under the ceiling and vertical direction along the center of the tunnel. Smoke front velocity and temperature decrease rate were reduced as higher aspect ratio of the tunnel cross-section. Smoke movement was evaluated by analysis of vertical temperature distribution 3 m downstream from the fire source. Elevation of smoke interface according to N percent rule was under about 60% of tunnel height.

• Journal of the Ergonomics Society of Korea
• /
• v.26 no.2
• /
• pp.89-102
• /
• 2007

Generally, it is well known that driving in tunnel imposes large burden to driver because of spatial constraint, limited visual field and so on. And such a burden of driver result in high accident occurrence. In this reason, studies dealing with features of driving and traffic flow in tunnel have been performed. However, information about characteristics of drivers and traffic in a very long tunnel is not accumulated yet. The purpose of this study is to identify the relations between tunnel length and burden of driver, driving patterns, traffic flow characteristics using the tunnel simulator that realizing various tunnel situations. For this, the tunnel simulation program was developed along 11km-length section. And biological data of 10 subjects gained from driving condition in simulation program was analyzed and compared with the result of real driving condition.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.947-954
• /
• 2008

Nowadays many urban subways are frequently constructed under the building and the river by the use of tunneling method. Especially, the majority of the tunnel are constructed even with shallow depth under the ground in the weathered soil. Since the tunnel are generally designed on the basis of the geographic soil investigation, the stability of the tunnel should be checked with the realistic data instrumented during construction. The displacement of the tunnel occurs in front of the end face during the excavation of the tunnel, which is called as pre-displacement. The total displacement can be figured from the exact pre-displacement, which is very difficult to measure without using any device installed in front of the tunnel end face. In this study, the pre-displacement measured from horizontal inclinometer was analyzed to know the co-relation with the total displacement and also, the trend and the characteristics of the tunnel deformation during construction was suggested through the regression analysis of the measured data.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.13 no.1
• /
• pp.33-50
• /
• 2011

Recently interest in enlargement of existing tunnel located in downtown or mountain area have been considerably increased along with requirements and discussion on the road-widening. Therefore, it is necessary to study the construction method and stability of tunnel to enlarge the existing tunnel in design. In this study, the design concept on the alignment, excavation method, reinforcement to enlarge the existing tunnel is described on the basis of the enlargement of 2-lane road tunnel under construction. This paper suggests a proper design method for the enlargement of an existing tunnel in useful practice.

• Geomechanics and Engineering
• /
• v.21 no.2
• /
• pp.133-142
• /
• 2020

Submerged floating tunnel (SFT) is a type of tunnel which causes the tunnel segments to float in the water. When the SFTs are connected to the ground, the connection between the SFT and the subsea bored tunnel is fragile due to the difference in behavioral characteristics between the two types of tunnels. Therefore, special design and construction methods are needed to ensure the stability of the area around the connection. However, since previous research on the stability of the connection site has not been undertaken enough, the basic step necessitates the evaluation of ground behavior at the shore connection. In this study, the numerical analysis targeting the shore connection between the subsea bored tunnel and the SFT was simulated. The strain concentration at the shore connection was analyzed by numerical simulation and the effects of several factors were examined. The results showed the instability in the ground close to the shore connection due to the imbalance in the behavior of the two types of tunnels; the location of the strain concentration varies with different environmental and structural conditions. It is expected that the results from this study can be utilized in future studies to determine weak points in the shore connection between the submerged floating tunnel and the subsea bored tunnel, and devise methods to mitigate the risks.

• 한국전산유체공학회:학술대회논문집
• /
• 2010.05a
• /
• pp.10-13
• /
• 2010

The flow field in road tunnel is influenced by some facts such as piston effect of vehicle's move, operation of ventilation facilities, natural wind and buoyancy effect of fire plume. Among those, jet fan is one of main ventilation facilities especially in longitudinal ventilation system of tunnel. In this study to analyze tunnel flow induced by operation of jet fan, numerical simulation has been carried out. The velocity distributions and streamlines in tunnel are examined to consider the three-dimensional characteristics of tunnel flow caused by jet fan.

• Journal of Environmental Health Sciences
• /
• v.19 no.4
• /
• pp.9-13
• /
• 1993

This paper describes the impact of reflected sound in tunnel. The impact of reflected sound is obtained from making a comparision between measurements of tunnel and bridge. Sound level of tunnel is higher than that of bridge because reflected sound is generated in tunnel. Road traffic noise cannot be freely propagated because there are many buildings in urban. Therefore, a tunnel effect is generated in urban road. The impact of reflected sound is generated not only in tunnel, but also in urban road. This study provides the basic data for tunneling work and noise control strategy in urban road.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.09a
• /
• pp.1294-1301
• /
• 2010

In this study, a case study, where a hazard management for tunnel collapses has been quantitatively undertaken based on the KICT Tunnel Hazard(KTH) index, is presented. From this, it was able to timely inform the field engineers when the more detailed investigation is required for checking if any risky factor is shown on the tunnel face. At the same time, variable additional information such as sensitivities of major influence factors are also provided to field engineers from the methodology given in this study. The additional information would be helpful for better understanding of tunnel hazard level at the current tunnelling stage and following the required actions for more detailed checks of risky factors.