• 산업기술연구
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• 제26권A호
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• pp.17-28
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• 2006

In underground drilling and blasting, particularly in small headings(generally under $20m^2$), the prospects for changes of blast parameters are usually more limited than those employed by large area tunnel(over $20m^2$). It is also well known that the consumption of explosives and specific drilling rate for small tunnel areas are exponentially increased also tunnel areas decrease. To confirm above results, some tests for two tunnels(irrigation water tunnel with $6.0m^2$ area, electric supplies tunnel with $15.0m^2$) are also carried out in this study. As a results, specific drilling rate and specific charge for irrigation water tunnel were decreased from 13.8 to $7.7m/m^3$ and from 4.88 to $2.56kg/m^3$ respectively. Those for electric supplies tunnel were also decreased from 8.0 to $4.9m/m^3$ and from 3.46 to $2.22kg/m^3$.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.285-292
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• 1999

Recent development cases of transportation utilities using tunnelling method in metropolitan sites have been increased due to the heavily complex environments and restrictions of construction works. The progress of tunnel design and construction to be supported by the tunnel analysis and measurement techniques using computers have increased adoptions of large section tunnels. In this paper, many factors to be considered in designing large section tunnels are discussed and the case of the construction of the subway station tunnel which is recently completed is introduced. This tunnel has a width of 24 m, a height of 16 m, and a excavation section area of 366 ㎡.

• Geomechanics and Engineering
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• 제35권4호
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• pp.395-409
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• 2023

Long-span suspension bridges have tunnel anchor systems to maintain stable cables. More investigations are required to determine how closely tunnel excavation beneath the tunnel anchor impacts the stability of the tunnel anchor. In order to investigate the impact of the adjacent tunnel's excavation on the stability of the tunnel anchor, a large-span suspension bridge tunnel anchor is utilised as an example in a three-dimensional numerical simulation approach. In order to explore the deformation control mechanism, orthogonal tests are employed to pinpoint the major impacting elements. The construction of an advanced pipe shed, strengthening the primary support. Moreover, according to the findings the grouting reinforcement of the surrounding rock, have a significant control effect on the settlement of the tunnel vault and plug body. However, reducing the lag distance of the secondary lining does not have such big influence. The greatest way to control tunnel vault settling is to use the grout reinforcement, which increases the bearing capacity and strength of the surrounding rock. This greatly minimizes the size of the tunnel excavation disturbance area. Advanced pipe shed can not only increase the surrounding rock's bearing capacity at the pipe shed, but can also prevent the tunnel vault from connecting with the disturbance area at the bottom of the anchorage tunnel, reduce the range of shear failure area outside the anchorage tunnel, and have the best impact on the plug body's settlement control.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.601-612
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• 2005

In mountainous area, Two parallel tunnels have been usually recognized as a road tunnel which has benefits in aspects of cost and stability. However, Design and construction of 2-Arch road tunnel are growing recently due to environmental destruction, compensation of land and difficulty of route separation. As studies are mainly undergoing on only guaranteeing stability and developing a waterproofing-drainage system to avoid water leakage through comprehension for characteristics of 2-arch tunnel behaviors, there is a tendency to evaluate quantity of support by empirical method with a tunnel which has a complicated cross-section and lack of construction ability. In this study, therefore, we made a plan of tunnel cross-section which had shown good construction ability and developed the waterproofing-drainage system which is able to solve the water leakage problem fundamentally by analyzing precedented 2-arch tunnels and investigating their sites in and out of nation. We also determined fixed quantity of support by a large-scale model test and numerical analysis. We want to contribute to 2-arch tunnel design hereafter introducing design procedure and method applied here.

• 한국터널지하공간학회 논문집
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• 제9권2호
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• pp.171-182
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• 2007

도심지 개착구간의 교통 및 환경적인 영향을 최소화하기 위하여 단면적 $200\;m^2$ 이상의 정거장터널이 퇴적암반 중에 계획되었으나 토피고가 13 m 이하인 설계조건에 직면하게 되었다. 본 연구에서는 패턴설계가 아닌 시공사례와 아칭효과 발현을 기초로 세 가지 요소 - 단면형상의 영향, 작용하중의 적용방법, 지보방안과 터널안정성분석 - 를 중심으로 설계방향이 논의되었다. 단면형상의 역학적인 영향에 기초하여 기본설계안과 연구단면안이 유도되었고, 지보방안은 터널천반부의 침하방지 및 역학적인 평형상태를 유지하기위한 파이프루프 보조공법과 NATM의 지보원리를 활용하였다. 두 설계안의 비교분석으로부터, 터널라이닝을 개착구조물의 연장선상에서 제약한 설계조건과 터널안정성 및 철근배근의 시공성에 대해 기본설계안이 적합한 방안임을 확인할 수 있었다. 그리고 동일한 건축한계로 아치부의 응력집중이 발생되지 않는 안정적인 응력분포를 나타내는 연구단면안의 분석결과에서 보듯이 향후 대단면터널 설계기술의 향상을 위해 단면형상의 영향과 이완하중의 적용방안이 심도 있게 검토되어야 함을 알 수 있다.

• 화약ㆍ발파
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• 제20권3호
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• pp.59-71
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• 2002

The points of this design case are the planning and excavation method of a new double-tracked railroad tunnel which is approx. 11∼22 meters apart from existing single-tracked railroad tunnel. For the optimum excavation method some needs are required in design stage, such as the reduction of noise and vibration, public resentment, damage of buildings and construction costs. Hence the estimation and application of allowable noise and vibration criterion is important. The ground coefficient (K, n) of this site is determined by field trial blasting. The excavation method is chosen to satisfy the allowable noise and vibration criterion. In addition, in order to ensure the stability of existing single-tracked railroad tunnel, the instrumentation of maintenance level is accompanied during the construction stage. As a result of this design condition, central diaphragm excavation with line drilling and pre-large hole boring blasting is applied to the area within 15 meters apart from existing tunnel. And above 15 meters apart, pre-large hole boring blasting is designed.

• 한국환경생태학회지
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• 제31권1호
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• pp.104-111
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• 2017

터널은 산림 훼손면적이 다른 공법에 비해 입구부와 출구부만 훼손하면서 도로가 지하로 건설되기 때문에 훼손면적을 줄일 수 있다는 장점이 있다. 본 연구는 터널 건설 시 산림이 훼손되는 터널입출구부를 중심으로 주변 지형과 관계를 살펴보고, 훼손면적을 최소화하고 지형 훼손을 저감할 수 있는 방향을 제시하기 위해 진입유형별 훼손면적을 살펴보고자 하였다. 연구는 국내 주요도로의 터널 150개를 선별하여 입구부와 출부구를 합쳐 300개 지점에 대해 진입유형을 구분하고 터널 진입부 훼손면적과 터널 상부 훼손면적을 산출하였다. 터널조성 위치에 따른 통계분석결과 진입유형별 훼손면적은 통계적 유의성이 인정되었다. 경사면직교형은 다른 진입유형에 비해 터널입출구부의 훼손면적은 작았으며, 반대로 골짜기진입형, 경사면평행형은 다른 진입유형에 비해 훼손 면적이 크게 나타났다. 지형을 고려한 터널위치 선정은 터널 1개소 당 최대 약 1.5ha 정도의 산림훼손을 줄일 수 있을 것으로 조사되었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.462-469
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• 2011

The design of high-depth and large-section tunnel facilities has been increased lately. The purpose of the design is to avoid inference of existing facilities, enhance public relations and reducing the size of the station, which is advantageous for effective use of underground spaces. Diverse downtown tunnel experience, advanced excavation equipment, reinforcement methods, monitoring technologies and numerical analysis made the design possible. This paper is to introduce the design of high-depth and large-section tunnel facilities via Gimpo airport area of Deagok-Sosa railway BTL project of double-tracking.

• 융복합기술연구소 논문집
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• 제11권1호
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• pp.25-28
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• 2021

Recently, the fire safety of road tunnels has been important issues in South Korea. However, proper fire safety regulations has not made for road tunnels. Due to geographical challenges in South Korea, road tunnels should be constructed to secure stable traffic flows. In the Guidelines for Installing and Managing Disaster Prevention Facilities of Road Tunnels (NFSC 603), main target vehicles are passenger cars. This guidelines cannot support big fires from larger vehicles such as cargo, oil trucks. In this study, fire safety for a road tunnel in port area was analyzed with fire dynamics theory under cargo truck fire scenario. Sujunsan road tunnel in Busan city was chosen as a target tunnel, which links between Busan port and highways to increase cargo shipping. The results show the limitations of present guidelines (NFSC 603) for road tunnel from large fire situations.

• 한국철도학회논문집
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• 제8권6호
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• pp.513-519
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• 2005

The Korean Tilting Train eXpress may produced a strong micro-pressure wave in tunnel exit because of large train/tunnel area ration of conventional railways. This micro-pressure wave causes an impulsive noise which is a serious environmental noise pollution near tunnel exit. Tunnel hood can be the method of reducing the micro-pressure wave in tunnel exit. Therefore, parametric studies for tunnel hood are performed with respect to the hood length and size to investigate the effects of the tunnel hood. Also, axi-symmetric unsteady compressible flow solver was used to analyze train-tunnel relative motion. According to the result of numerical analysis, the maximum micro-pressure wave in tunnel exit is reduced by 56% throughout the hood establishment on conventional railways.