• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.140-153
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• 2005

During the tunnel construction the major failure mode can be categorized as: tunnel failure just after the tunnel excavation without support, failure after application of shotcrete and finally failure after setting the concrete lining. The failure mode just after the tunnel excavation without support, can be further classified as : bench failure, crown failure, face failure, full face failure, failure due to weak strata and failure due to overburden. Moreover the failure after application of shotcrete is classified as heading face failure, settlement of shotcrete support, local failure of shotcrete lining and invert shotcrete. To find out the major causes of tunnel collapse, the investigation was done in case of the second phase of Seoul subway construction. The investigation results depicted that the major causes of tunnel collapse were due to the weak layer of rock/fault and sudden influx of ground water from the tunnel crown. While the investigation results of the mountain road tunnels construction have shown that the major causes of tunnel failure were inadequate analysis of tunnel face mapping results, intersection of faults and limestone cavities. In this paper some recent measurement in order to mitigate such tunnel collapse are presented

• 한국도로학회논문집
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• 제16권3호
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• pp.51-57
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• 2014

PURPOSES : This study is to suggest tunnel length to spray curing compound, based on the field tests. METHODS : At first field test, length from the entrance of tunnel to wet wall was checked by visual survey. The second and third test, various sensors were installed in concrete or in tunnel, such as RH sensor, temperature sensor, portable weather station and etc.. And also, test for bleeding and retaining water of concrete were conducted to evaluate environmental effect on concrete pavement. RESULTS : The result of the field experiment for tunnel length to spray curing compound indicates that length changes depending on tunnel length, season, and location. Environmental condition of a short tunnel was not much different between location near entrance and at center of tunnel. However, in case of a medium and long tunnel, effect of outside environmental condition decreased, when location moved into tunnel center of it. CONCLUSIONS : From the testing results, it can be proposed that optimum tunnel length to spray curing compound is 60m for a medium and long tunnel, and whole length for a short tunnel.

• 한국구조물진단유지관리공학회 논문집
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• 제8권4호
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• pp.145-152
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• 2004

적색 침전물은 철성분이 가장 많이 포함되어 있었는데 이는 흙막이공과 지역 특성상 철분을 많이 포함하고 있는 지하수에 원인이 있는 것으로 판단된다. 백색 침전물의 경우 가장 많이 발견된 성분은 산화칼슘으로 건설당시 지반보강을 위하여 시행한 그라우팅 주입재인 시멘트가 지하수와 함께 터널 내부로 유입된 침전물로서 터널의 안전성에는 영향이 없을 것으로 판단된다. 흑색 침전물은 정거장 시점 및 종점 근접부 터널에서 발생되고 있으며, 이는 청소용수 퉁 이물질이 터널 내 배수시설로 유입되어 백색 또는 적색 침전물과 혼합된 침전물이다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.303-308
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• 2004

It is recently reported that the importance of environmental impact assessment(EIA) about groundwater outflow problems is beingy raised in the case of tunnel excavation during railroad construction. The EIA about groundwater outflow into railroad tunnel is generally performed using the results of numerical analysis embodied through groundwater flow modeling program like MODFLOW. The basic data for this modeling include (1) the geological and hydrogeological investigation data along the planned block of tunnel excavation, (2) total amount of outflowed groundwater during tunnel excavation, and (3) the status of groundwater level fluctuation in the water-supply wells distributed in the planned block of tunnel excavation. In this study, the authors analyzed the cases of the computational modeling about groundwater outflow in three planned blocks of railroad tunnel, and suggest the environmental impact factors and mitigation plan during EIA of tunnel excavation in railroad construction.

• 한국해안해양공학회지
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• 제17권4호
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• pp.294-306
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• 2005

지금까지 침매터널에 대한 대부분의 연구들은 건설기술자의 경험에 바탕을 둔 연구들이었다. 공학적인 관점에서 파랑하중에 의한 침매터널의 안정성은 지반기초의 거동에 큰 영향을 받으므로 파${\cdot}$지반${\cdot}$침매터널의 상호작용에 대한 이해는 매우 중요하다. 본 연구에서는 파${\cdot}$지반${\cdot}$침매터널의 상호작용의 메커니즘에 대한 이해를 위하여 부산-거제간 연결도로 민간투자사업 구간 중 침매터널 구간에 직접수치해석기법을 적용하여 침매터널 주변의 지반 및 피복층 내에서 파랑하중에 의한 간극수압, 와도 및 흐름의 특성을 종합적으로 살펴보았다. 또한 다양한 파랑조건 및 피복층의 평균입경변화에 따른 비선형성의 파랑과 침매터널 및 지반의 상호작용이 침매터널의 안정성과 관련하여 논의되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.151-154
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• 1999

The lining concrete of water tunnel is a structure that is constructed to prevent from corroding of the rock around tunnel and reduce the deterioration of geology by flowing water, and to improve the durability of tunnel, which must not only economy, stability but also satisfy the engeneering properties of concrete. This is an experimental study to analyze th usability of fly in the tunnel lining concrete. For this purpose, after select the mix proportion of plain concrete and concrete using fly ash(the replacement of 15 and 30% by weight of cement) to satisfy slump, air content and compressive strength through the mix design, the test of slump, setting time, compressive strength, tensile strength, drying shrinkage and adiabatic temperature rise was performed. According to test results, it was found that FA 15 concrete was more effective than the others to reduce drying shrinkage as well satisfy other engineering properties.

• 지질공학
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• 제7권1호
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• pp.1-10
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• 1997

우리나라가 물류난을 극복하고 지속적인 경제발전을 위해서는 한강과 낙동강을 잇는 경부운하의 건설이 필요하다. 경부운하는 한강 신곡수중보에서 시작하여 팔당, 강촌, 조정지, 동량 2단, 충주 및 송계댐의 갑문을 거쳐 높이 125m, 길이 20.5km의 조령터널에 이르며, 터널은 수평으로 낙동강 상류와 연결된다. 지질 및 지형도상에서 확인된 한강 구간의 댐과 터널 구조물의 입지는 양호한 것으로 판단되며, 높은 갑문의 운용으로 인해 다량으로 소비되는 용수의 확보도 충주호의 상류에 댐을 추가 건설하거나, 절수갑문의 도입으로 해결가능한 것으로 나타났다.

• Geomechanics and Engineering
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• 제18권3호
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• pp.235-245
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• 2019

This paper presents a novel methodology for face stability assessment of rock tunnels under water table by combining the kinematical approach of limit analysis and numerical simulation. The tunnels considered in this paper are excavated in fractured rock masses characterized by the Hoek-Brown failure criterion. In terms of natural rock deposition, a more convincing case of depth-dependent mi, GSI, D and ${\sigma}_c$ is taken into account by proposing the horizontally layered discretization technique, which enables us to generate the failure surface of tunnel face point by point. The vertical distance between any two adjacent points is fixed, which is beneficial to deal with stability problems involving depth-dependent rock parameters. The pore water pressure is numerically computed by means of 3D steady-state flow analyses. Accordingly, the pore water pressure for each discretized point on the failure surface is obtained by interpolation. The parametric analysis is performed to show the influence of depth-dependent parameters of $m_i$, GSI, D, ${\sigma}_c$ and the variation of water table elevation on tunnel face stability. Finally, several design charts for an undisturbed tunnel are presented for quick calculations of critical support pressures against face failure.

• Journal of Information Processing Systems
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• 제15권6호
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• pp.1350-1364
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• 2019

The ice damage occurs frequently in cold and dry region of western China in winter ice period and spring thaw period. In the drift ice condition, it is easy to form different extrusion force or impact force to damage tunnel lining, causing project failure. The failure project could not arrive the original planning and construction goal, giving rise to the water allocation pressure which influences diversion irrigation and farming production in spring. This study conducts the theoretical study on contact-impact algorithm of drift ices crashing diversion tunnel based on the symmetric penalty function in finite element theory. ANSYS/LS-DYNA is adopted as the platform to establish tunnel model and drift ice model. LS-DYNA SOLVER is used as the solver and LS-PREPOST is used to do post-processing, analyzing the damage degrees of drift ices on tunnel. Constructing physical model in the experiment to verify and reveal the impact damage mechanism of drift ices on diversion tunnel. The software simulation results and the experiment results show that tunnel lining surface will form varying degree deformation and failure when drift ices crash tunnel lining on different velocity, different plan size and different thickness of drift ice. The researches also show that there are damages of drift ice impact force on tunnel lining in the thawing period in cold and dry region. By long time water scouring, the tunnel lining surfaces are broken and falling off which breaks the strength and stability of the structure.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1768-1772
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• 2008

The authors previously presented that the experimental technique using fine bubbles generated by electrolysis simulated fire behavior in a tunnel. We improve this experimental setup to enable this to be considered tunnel-ventilation by circulation of salt water. In this paper we introduce the new experimental setup and the visualization of fine hydrogen bubbles simulated smoke in a ventilated tunnel by using a laser sheet are presented.