• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 가을 학술발표회 논문집
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• pp.231-237
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• 2001

This paper presents some proposed methods for discontinuum analysis with rock discontinuities data acquisited in tunnel design stage. The limit equilibrium method for rock block sliding and falling proposed in this paper can consider the tunnel excavation and support stage, and, to the extent, the standard deviations and means of joint set orientation. Simple Distinct Elemet modelling methods are recommended in estimating the stability of tunnels in jointed rock masses. Because, the simple models are likely to show more consistent and clear than very complex model with finite joint length and joint deviation parameters.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1169_1170
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• 2009

This paper introduces insulator pollutant accumulate pattern in the tunnel of korea railroad. To accomplish this goal, effective sample collecting method was proposed for the first step. Dust at the surface was collected directly. Distilled water and brush was used while collecting. Through this method dust is easily and accurately collected. The second step is pollutant analysis. Several analyze item is selected such as quantity, conductivity, contact angle, Optical Microscope(OM), IR, Equivalent Salt Deposit Density(ESDD), and ICP-AES. The third step, best represent tunnel was selected considering location, length and natural surroundings. Also to consider the difference at inside the tunnel, several bracket insulators were selected along to the location. To make the result precise, above procedure was repeated several times at the same target. Finally relation among type of train, numbers of movement, surroundings, length will be considered in combination with the pollution. With this result pollute map for KORAIL could be accomplished and inspect period will be optimized case by case.

• 대한기계학회논문집B
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• 제21권11호
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• pp.1413-1421
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• 1997

A new control method to alleviate the impulsive noise at the exit of high-speed railway tunnel was applied to the compression wave at the entrance of the tunnel. This method uses the interaction phenomenon of unsteady expansion wave and unsteady compression wave. Unsteady expansion wave was assumed to be made instantaneously by the simple theory of shock tube. Total Variation Diminishing method was employed to solve the axisymmetric unsteady compressible flow field with a specified compression wave. Numerical results show that the maximum pressure gradient of the propagating compression wave decreases with increase of the wave length of the unsteady expansion wave. It is found that the impulsive noise reduction can be obtained when the unsteady expansion wave with a large wave length is emitted just before the train enters the tunnel. The present results give the possibility to reduce the impulsive noise at the exit of tunnel.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.611-613
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• 2016

TCAD 시뮬레이션을 이용하여 소스영역으로 오버랩된(overlapped) 게이트를 가진 터널링 전계효과 트랜지스터(Tunnel Field-Effect Transistor; TFET)의 오버랩된 게이트 길이에 따른 터널링 전류 특성을 조사하였다. 터널링은 크게 라인터널링과 포인트 터널링으로 구분되는데, 라인터널링이 포인트터널링보다 subthreshold swing(SS), on-current에서 더 높은 성능을 보인다. 본 논문은 Silicon, Germanium, Si-Ge Hetero TFET구조에서 게이트 길이를 소스영역으로 오버랩될 경우에 포인트 터널링과 라인터널링의 효과를 조사해서 SS와 on-current에 최적합한 구조의 가이드라인을 제시한다.

• 대한건축학회논문집:구조계
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• 제34권4호
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• pp.59-64
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• 2018

Construction schedule acceleration due to unreasonable construction planning frequently leads to construction accidents. In order to avoid such inevitable acceleration and to ensure safety in construction sites, there is a need for objective standards to determine appropriate construction duration for each construction process earlier in the process. In order to achieve the goal, intensive experts interviews were firstly conducted to identify candidate drivers affecting construction schedule of road tunnel excavation works. Then, a total of 34 field data was collected from on-going sites to analyze. It was found that actual excavation length per one day on site is varied mostly by Rock Mass Rating(RMR) types from various statistical analyses. Therefore an one-way table of excavation length per a day by RMR types were presented in a form of percentile. The results will help industry experts determine the most appropriate construction schedule for the works, which eventually lead to a zero accident site in many ways.

• 한국화재소방학회논문지
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• 제16권3호
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• pp.71-76
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• 2002

실제 터널화재에서의 위험성을 평가하기 위하여, 국내에서 최초로 실물터널 화재실험이 수행되었다. 길이 465m의 터널에서 0.25MW에서 2.5MW까지의 가솔린 풀과 1500cc승용차를 화원으로 사용하였으며, 터널내의 유속을 조정하기 위하여 6대의 제트팬을 설치하였다. 터널내의 온도분포와 연기거동을 살펴보기 위하여 총 86곳의 온도를 측정하였다. 다양한 조건에서의 풀화재와 자동차 화재의 성상을 비교하였으며, 실험 결과 각종 화재 조건에서의 연기의 역류, 하강, 터널 내 온도분포 등과 같은 실제 터널 화재상황에서 피해에 영향을 미치는 각종 인자들을 파악하였다.

• 한국지반공학회지:지반
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• 제12권1호
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• pp.87-110
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• 1996

터널굴착시, 막장부근의 3차원 효과를 반영하기 위해 주로 경험적인 하중분담률 개념을 도입한 2차원 유한차분법 수치해석이 수행된다. 본 논문에서는 3차원 수치해석을 수행하고 그 해석 결과와 2차원 수치해석 결과를 비교함으로써 합리적인 하중분담률의 적용 가능성 및 막장 부근의 음력집중 문제를 규명하고자 하였다. 무지보 굴착길이, 초기지중응력, 지반종류, 단면크기와 터널심도등의 하중분담률에 주된 영향을 미치는 인자들에 대한 매개변수 연구를 수행하고, 그 결과를 토대로 서울지하철의 대표적인 단면에 대해 적용가능한 하중분담률을 추천하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.829-834
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• 2009

Alluvial soil is one of the most difficult grounds for tunneling works due to the insufficient ground strength and excessive ground water inflow. Dduk island in Seoul has a wide alluvium developed by two rivers, Han and Jung-Ryang. Subway tunnel of $\bigcirc\bigcirc$ line planed across Dduk island has highly poor ground conditions due to small cover and deeply developed alluvium. Moreover, much part of this tunnel is located parallel to the bridge foundations of another railway with a small horizontal distance. Original design was done in 2002 and construction has been in progress. During the construction, tunnel design has been partly changed and adjusted for the complex ground condition and the demand from related organizations. This paper intend to introduce the urban tunnel design and construction in alluvial soils. This line could be divided three sections(A, B, C) according to ground and adjacent conditions. Section A is featured by mixed tunnel faces consisted with alluvial soils and weathered or weak rocks. The feature of section B is that tunnel underpasses near the bridge foundations of another subway. Lastly, section C with a very short length is the most difficult construction conditions due to the small cover, poor ground, obstacles on and underneath ground surface.

• 한국암반공학회:학술대회논문집
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• 한국암반공학회 2008년도 국제학술회의
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• pp.33-41
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• 2008

The longest tunnel has been halted at Daekwanryung by the failure of the host country of the Winter Olympiad in 2014, but modern High-Power TBM will come to Korea to excavate these long tunnels to establish the better horizontal connection between the western and eastern countries to improve the strong powerful logistic strategy of Korean peninsula. Train operation provides a key function of air movements in a long underground tunnel, and heat generation from transit vehicles may account of the most heat release to the ventilation and emergency systems. This paper indicates the optimal fire suppress services and safety provision for the long railway tunnel which is designed twin tunnel with length 22km in Gangwon province of Korea. The design of the fire-fighting systems and emergency were prepared by the operation of the famous long-railway tunnels as well as the severe lessons from the real fires in domestic and overseas experiences. Designers should concentrate the optimal solution for passenger's safety at the emergency state when tunnel fires, train crush accidents, derailment, and etc. The optimal fire-extinguishing facilities for long railway tunnels are presented for better safety of the comfortable operation in this hard rock tunnel of eastern mountains side of Korea. Since year 1900, hard rock tunnel construction has been launched for railway tunnels in Korea, tunnels have been built for various purposes not only for infrastructure tunnels including roadway, railway, subway, and but also for water and power supply, for deposit food, waste, and oils etc. Most favorable railway tunnel system was discussed in details; twin tunnels, distance of cross passage, ventilation systems, for the comfortable train operations in the future.

• 한국가시화정보학회지
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• 제16권3호
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• pp.8-15
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• 2018

Recently, as the high speed railway becomes more common, new environmental problems such as noise around tunnels are appearing. When a high speed train enters a tunnel, a compression wave in the tunnel is generated and propagated toward the tunnel exit at a sonic speed. When it reaches the tunnel exit, a part of compression wave radiates as a pulse typed impulse wave to the outside of tunnel. The impulse wave has an explosive noise. When the impulse wave is propagated around a village, it induces a serious noise or other problems to the resident. In order to solve these engineering problems, it is important to investigate the radiation characteristics of the impulse wave radiated from the tunnel exit. In this study, the effect of the length and angle of the baffle plate at the tunnel exit on the impulse wave radiated from the tunnel exit was investigated by numerical analysis. As a results, the baffle plate greatly affected the propagation of impulse wave.