• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.217-223
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• 1999

Mostly, water leakage took place in construction joints. In case of cable tunnels constructed by open-cut method, waterstops have been used to prevent the water leakage. But, we haven't any experience to install the waterstops in NATM cable tunnels. So, it is necessary to develope the waterstops and test the performance of it in laboratory. We manufactured cable tunnel lining quarter scale model by pouring concrete, and installed the waterstops. After filling the inside of concrete lining about two-third with water, we put the air pressure on the water, In addition, it is also carried out water leakage test for concrete lining model without waterstops. As a result, we confirmed the performance of waterstops and its adaptability. It is also tested that the performance of rubber gaskets used in concrete segments of Shield tunnelling. In addition, we determined the allowable infiltration rate for cable tunnel with non-drainage system.

• 한국산업융합학회 논문집
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• 제25권4_2호
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• pp.587-594
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• 2022

In the 2000s, a lot of cable-type grand bridges are being built in consideration of economic aspects such as the reduction of logistics costs and the distribution of traffic volume due to rapid economic development. In addition, because the recently installed grand bridges are designed in an aesthetic form that matches the surrounding environment as well as the original function of the road bridge, and serves as a milestone in an area and is used as an excellent tourism resource, attracting many vehicles and people, there is an urgent need for a safety structure that can ensure the safety of not only vehicles but also people. In order to make cable-stayed bridge safe on wind for additional five safety structures, main girder models with and without safety structures for wind-tunnel experiments was made, and wind tunnel experiments was carried out to measure aerodynamic force coefficients. Also, wind-resistant analyses of 3D cable-stayed bridge were performed on the basis of wind-tunnel experiment results. From the wind tunnel experiments for the aerodynamic force coefficients of main girder with five safety structures and the wind resistant analyses of cable-stayed bridge without safety structure and with safety structure, it was concluded that the best form of wind-resistant safety was shown in the order of mesh, standard, bracing, hollow, and closed type. And wind-resistant safety of cable-stayed bridge with hollow and closed type on design wind speed 68.0m/sec was not secured. Finally, as five safety structures are installed, maximum rate of stress increments was shown in the order of steel main beam, steel floor beam, concrete floor beam and cables.

• 화약ㆍ발파
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• 제13권4호
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• pp.28-38
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• 1995

This paper was addressed by fall seminar of society of explosives engineers of Korea. In Japan, total length of cable was 600km and tokyo was 260km and it will extend cable tunnel 5~10km every year in Tokyo. NTT service project has been working as a optic fiber net works and in 2010, it will be done. FIF. FTTH so call fiber to the home for the purpose of multiplicity. For the above project. First, it should be developing auto Non-excavation tech, 2nd developing soil recycling system.

• Wind and Structures
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• 제22권2호
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• pp.253-272
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• 2016

The paper concerns with the method and results of wind tunnel investigations of the Strouhal number (St) of a stationary iced cable model of cable-supported bridges with respect to different angles of wind attack. The investigations were conducted in the Climatic Wind Tunnel Laboratory of the Czech Academy of Sciences in $Tel{\check{c}}$. The methodology leading to the experimental icing of the inclined cable model was prepared in a climatic section of the laboratory. The shape of the ice on the cable was registered by a photogrammetry method. A section of an iced cable model with a smaller scale was reproduced with a 3D printing procedure for subsequent aerodynamic investigations. The St values were determined within the range of the Reynolds number (Re) between $2.4{\cdot}10^4$ and $16.5{\cdot}10^4$, based on the dominant vortex shedding frequencies measured in the wake of the model. The model was oriented at three principal angles of wind attack for each of selected Re values. The flow regimes were distinguished for each model configuration. In order to recognize the tunnel blockage effect the St of a circular smooth cylinder was also tested. Good agreement with the reported values in the subcritical Re range of a circular cylinder was obtained. The knowledge of the flow regimes of the airflow around an iced cable and the associated St values could constitute a basis to formulate a mathematical description of the vortex-induced force acting on the iced cable of a cable-supported bridge and could allow predicting the cable response due to the vortex excitation phenomenon.

• 한국터널지하공간학회 논문집
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• 제26권1호
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• pp.19-37
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• 2024

록볼트는 NATM터널의 주 지보재로서 터널공사 현장에 널리 이용되고 있다. 국내 터널 현장에서는 전면접착형 록볼트가 가장 많이 사용되고 있다. 전면접착형 록볼트는 그라우트에 의해 볼트체와 지반 간 상대적인 거동을 구현한다. 그러나 터널 수치해석 시 전면접착형 록볼트는 이러한 거동 특성이 반영되지 못한 방법으로 모델링되는 경우가 많다. 이러한 경우, 지보재의 부재력을 과소 혹은 과대 평가하는 요인이 될 수 있다. 본 연구에서는 전면접착형 록볼트의 합리적인 모델링 방법에 대한 연구를 수행하였다. 문헌 연구 결과, 전면접착형 록볼트는 Cable요소와 Truss요소로 모델링되는 것으로 분석되었다. Cable요소의 그라우트 물성치가 록볼트 거동에 미치는 영향을 분석하기 위해, 그라우트 물성치를 록볼트 인발시험 데이터를 통해 산정하여 적용한 모델과 록볼트와 지반 간 완전 접착을 가정하기 위해 임의로 크게 적용한 모델의 록볼트 거동을 비교하였다. 동일한 터널 조건에서 전면접착형 록볼트를 Truss요소와 Cable요소로 각각 다르게 모델링하여 수치해석을 수행하였고, 이에 따른 터널 거동을 분석하였다. 연구 결과, 록볼트와 지반 간 경계면 효과, 즉, 그라우트를 고려할 수 있는 요소로 전면접착형 록볼트를 모델링하는 것이 바람직한 것으로 검토되었다. 실제 전면접착형 록볼트의 거동을 모사하기 위해 인발시험 데이터를 활용하는 방법은 유효한 방법으로 검토되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1369-1376
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• 2005

In case of the drainage type tunnel, the residual water pressure is likely to act on the tunnel lining due to the decrease of water-passing capacity of the filter material. Therefore, this study discussions a method to predict the lining load with the consideration of water passing capacity of the filter material through the literature review and numerical analysis. It is expected from the results of case studies that the design load acting on the concrete lining in the drainage type tunnel could be assumed to be about 50% of the hydrostatic water pressure in steady-state ground-water condition.

• 한국초전도ㆍ저온공학회논문지
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• 제3권2호
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• pp.10-14
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• 2001

This paper presents the possible application of a HTS superconducting power cable fro transmitting electric power in metropolitan areas, reflecting its important distinction such as compactness for installation in underground ducts and considerable efficiency improvement comparable to present underground cables. In this paper, we investigated characteristic and market scale compact HTS transmission cable which is possible to install in under-ground ducts. and reviewed its economical efficiency comparing to present existed CV cable construction and duct or tunnel installation.

• 전기학회논문지
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• 제56권11호
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• pp.1879-1884
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• 2007

In the electric power industry, it is important that the supply of energy must be guaranteed. Many power utilities control and supervise the transmission line to avoid power failures. In case of underground tunnel, some troubles are reported in cable joint. To stabilize the power, it is needed to monitor the cable joint. Many researches of cable joint monitoring have been going on by partial discharge measurement and temperature measurement using optical cable. These methods need much cost to install and maintain, so it is only used in critical transmission line. In this research, we use wireless sensor technology, because of its low cost and easy installation. We develop the temperature monitoring system for cable joint. Temperature sensor is installed on the surface of cable joint and sends data to server through router node using wireless network. Generally Ad hoc routing is searched in wireless network. However, in this research, we design the static linear routing mechanism, which is suitable for electric power line monitoring and analyze the life time of the sensor node by measuring the amount of the battery consumption.

• 한국터널지하공간학회 논문집
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• 제16권2호
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• pp.213-224
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• 2014

최근, tunnel boring machine (TBM)을 이용한 도심지 지중 전력구 터널 건설이 증가하고 있다. 쉴드 TBM을 이용한 기계화 터널 굴착 공법은 재래식 공법에 비해 지반침하를 최소화 하고 발파에 의한 진동을 줄일 수 있는 장점이 있다. 국내에서는 earth pressure balance(EPB) 쉴드 TBM이 주로 사용되고 있다. 그러나 전력구 터널 굴착을 위한 쉴드 TBM 공법이 증가함에도 불구하고, 전력구 쉴드 TBM 터널의 거동 분석에 관한 연구는 미비한 실정이다. 본 연구에서는 후방주입 거리에 따른 전력구 쉴드 TBM 터널의 거동 특성을 분석하고, 굴착면 지반 손실과 후방주입 거리와의 상관관계를 도출하고자 한다. 쉴드 TBM을 이용한 터널 굴착은 3D FEM을 이용하여 시뮬레이션 하였다. 뒷채움 그라우트가 설치되는 거리의 변화에 따른 축력, 전단력, 휨 모멘트와 같은 단면력을 검토하고 지표면에서의 연직 변위를 분석하였다. 또한, 유한요소해석으로 얻어진 결과와 안정성 분석에 기초하여, 지반과 터널 구조물의 안정성을 확보할 수 있는 뒷채움재 주입시기를 결정할 수 있다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.984-991
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• 2008

In this study, to evaluate the slope and tunnel stabilization method using pc cable with bulbed. To estimate the application of tunnel support using field tests and numerical analysis results. The reinforcement effects of slope stabilization method reinforced by PC cables were estimated compared with conventional soil nail system that reinforce the slope using rebar.