• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.542-545
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• 2007

터널의 노면 양쪽에 관로를 설치하여 유입된 지하수를 배출시키는 방법은 일반적인 터널 배수공법이지만 배수관로의 설치를 위한 추가적인 굴착은 공사기간과 공사비의 상승으로 이어지는 실정이다. 이에 터널 내에 별도의 배수관로 굴착 없이 노면 하부에 다열기둥을 일정 간격으로 매설하여 지하수의 흐름방향을 노면 하부로 유도시키는 경제적인 배수시스템이 현재 연구 중이다. 이 터널배수시스템은 추가적 굴착이 없어 기존의 배수시스템보다 경제적이지만 다열기둥의 연속적인 배치를 필요로 하므로 기존의 관로배수방식보다 더 많은 유체의 흐름저항을 받게 된다. 따라서 유체의 흐름에 효율적인 다열기둥 간의 배치간격에 대한 연구가 필요하다. 그래서 본 연구에서는 노면 하부에 다열기둥이 매설된 터널 내로 유입하는 지하수 배출을 목적으로 다열기둥 간의 배치간격에 따른 Manning계수의 변화를 수리실험을 통해 측정 분석하였다. 특히 Manning계수는 개수로에서 유체흐름 저항의 정도를 파악하는 데 이용되는 인자로 이를 활용하여 지하수 배수에 적절한 다열기둥 배치간격을 산정하였다. 본 연구를 통해 얻어진 수리실험 자료는 노면하부에 다열기둥을 매설하는 터널공사의 실제 설계를 위한 기초적인 참고자료로 사용될 것으로 기대된다.

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

• Tunnel and Underground Space
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• v.14 no.6 s.53
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• pp.429-439
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• 2004

The deep underground High Level Waste (HLW) repository to dispose of 36,000tons of spent fuel from the reactors in Korea needs about $4km^2$ repository area. In this study, the deep undergrond repository layout was optimized to minimize the excavation rock volume as well as underground repository area. In the optimization, the results from thermal analysis were used to define the influence of tunnel and deposition hole spacings on repository layout. The repository area and excavation rock volume could be reduced with longer disposal tunnel length. When it is necessary to reduce the repository area with satisfying thermal criteria, it is better to reduce tunnel spacing and increase deposition hole spacing. In contrast, the excavation rock volume can be reduced by increasing the tunnel spacing and decreasing the hole spacing.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.4
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• pp.335-344
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• 2006

The domestic standards which used the standards of Road Association of Japan standards presents the distances of between jet-fans by the caliber of jet-fan. However, the Permanent International Association of Road Congress (PIARC) encourages it to be ten times a diameter of the tunnel. The distance of jet-fans installed in bases of two standards differs as much as two times, as so the proper basis after analysis of internal air current is needed since such difference can lead to disadvantage for selection of ventilation configuration. Based on Froude modeling theory, 1/40 scale acrylic model of a tunnel (215mm in diameter and 6.9m in length) and jet-fan (26.3mm and 31.6mm in caliber) was made for the measurement of changes in pressure and velocity due to the extension of tunnel for analysis of internal air current. And we measured the changes in pressure of surroundings of a jet-fan for confirmation of recirculation due to the exterior airs when the jet-fan is on. The results of the model test show that internal air current was not influenced by the caliber of jet-fan and its changes in pressure and velocity were stable in the point where it was nine times of diameter of the tunnel. Also the recirculation when the jet-fan is on could be verified. According to such results, in the cases of installing jet-fan in tunnels, the distances between jet-fans needs to be more than nine times the diameter.

• Journal of Korean Society of Transportation
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• v.20 no.2
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• pp.47-58
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• 2002

This thesis is based on the speed variations which are observed both in a sing1e tunnel and a continuous tunnel. Kumdae II tunnel and Chiak I tunnel of Jungang Expressway are selected in order to analyze the characteristics of speed variations according to tunnel intervals I place importance on the computation of tunnel intervals according to the speed variations. there's a summary of the results. The results of the study reveal that speed changes occur both on 1km ahead of tunnel and within the tunnel. The speed change amounts to 7.1km/hr(6.7%) on these survey Points 2.7km/hr (2.9%) on access points, and from -3.6km/hr (-3.8%) to, +4.1km/hr(+4.7%) irregularly on egress points. The magnitude of speed chance appears small on the survey points where an interval of tunnel is short whereas the speed chance turn out to be rather significant on the points where the tunnel interval is long. The analysis of tunnel distances using multiple regression models shows that the appropriate tunnel distance turns out to be 732m. The distance of 732m seem to be providing a fecundation for uniform traffic flow in continuous tunnel conditions.

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

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.1
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• pp.33-42
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• 2003

The use of tunnels in major transportation schemes has increased considerably during the last decade especially in urban area. The state of stress and the displacements in a zone around a tunnel will be modified by the construction of a tunnel. Therefore, it is necessary to study the influence factors for the nearby tunnels. This paper describes the design concept and analysis method on the closely spaced tunnels. The main purpose of the present paper is to study the influence of tunnel construction on the behaviour induced in the liners of nearby tunnels. The effects of tunnel proximity and alignment, liner stiffness and settlements are also reviewed in this paper. The paper then introduces the design and analysis methods for the closely spaced tunnels which is very useful in practice.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.61-70
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• 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
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• v.10 no.1
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• pp.81-90
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• 2008

It is of great importance to determine the optimum cutter spacing in TBM. In order to determine the optimum cutter spacing, a series of cutting tests by linear cutting machine (LCM) are performed with changing cutter space. This study showed that a numerical method for estimating the optimum cutter spacing could be developed by AUTODYN-3D in order to overcome the limitation of LCM test. By using this method, the optimum cutter spacing of Hwangdeung granite was estimated.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.509-517
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• 2022

The demand for underground infrastructures such as tunnels is expanding due to rapid urbanization. Tunnels in urban areas are usually constructed adjacent to structures supported by piles. Therefore, a proper understanding of pile-tunnel interaction due to tunnel excavation activities is vital. Thus, in this study, a numerical analysis is conducted to analyze pile settlements, ground surface settlements and shear deformations above an existing tunnel subject to the presence of an adjacent tunnelling, with vertical offsets, the number of piles and the pile spacing considered as variables in the analysis. The results show that the vertical offsets between the tunnel crown and the pile tip generatelarger settlement than the pile spacing. In addition, the vertical offset shows an inversely proportional relationship to the shear deformation due to new tunnelling.