• The Journal of Engineering Geology
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• v.8 no.2
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• pp.153-161
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• 1998

An anisotropic characteristics of stratified sedimentary rocks should be considered in the design of tunnel. The second line of Taegu subway is under construction through the sedimentary rocks which is stratified by alternation of shale and sandstone, and Tongsoe over bridge road is planned to be constructed along the subway line. Thus the subway twin tunnels will be subjected by the bridge load of 76.2 MN per pier that will be placed in between the twin tunnels of the subway line. A numerical analysis is carried out for the stability of the twin tunnel, and the result shows that the maximum principal stress of surrounding ground is increased by 5∼6 MPa and the additional displacement of concrete lining is reached up to 8∼10mm due to the external bridge load. For the safety operation of the subway, reinforcement of the tunnel structure is highly recommended.

• Journal of Environmental Policy
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• v.7 no.1
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• pp.31-52
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• 2008

It has been attempted to minimize the environmental impacts due to railroad and road constructions. But assessments of the impact for the unwanted discharges by tunneling are still poorly systematic due to lack of scientific evaluation results ; thus, the tunneling projects frequently cause wide social conflicts. The goal of this study is to provide a guideline for appropriate environmental impact forecasts, assessments, and mitigation planning of tunneling projects.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.3
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• pp.257-267
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• 2008

Tunnels acting as drains involve groundwater-related problems such as deterioration of drainage systems or leakage through the linings. Generally initial and minor leakage problems can not be recognized by naked eyes. When the leakage over the linings is noticed, damages to structures and facilities have already occurred and could be considerable. Therefore it is vital to recognize initial leakage as early as possible and provide appropriate measures. Detection of leakage under operation requires installing piezometer. However, that may cause destruction of water proofing sheet which is generally not allowed. In this study electric resistivity method, one of the geophysical surveys, was adopted to detect possible leakage through tunnel linings. Physical lining models were made in the laboratory. The electric response was monitored for varying hydraulic conditions. It is shown that the method is very useful to detect initial leakage and monitor the malfunction of drainage system. Furthermore the method can also be used to check the quality of any repairing works of linings.

• Tunnel and Underground Space
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• v.22 no.5
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• pp.310-320
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• 2012

This paper describes the design and construction of a 2-arch tunnel with varying section. This new design has advantages of 2-arch tunnels, which is rather expensive, but is still economically competitive compared to parallel tunnels. Economic analysis was also conducted. To secure the stability of the varying section tunnel, excavated part was reinforced by tie-bolts and RRS, and 2-arch part was supported by EPS blocks and concrete walls. Stability of the pillar was theoretically analyzed and also examined by numerical simulations for various widths. Displacement monitoring was conducted and results were compared with numerical results. Economic analysis showed reductions in construction cost and period by 11% and 10 months respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.6
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• pp.1937-1944
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• 2014

In recent years, common ducts have been installed and operated in the sidewalls of tunnels to prepare for emergencies in tunnel construction and maintenance. The installation of common ducts is done mainly by humans. Problems with cost increases are inherent in tunnel construction by humans due to the safety risks and the economic inefficiency of humans performing construction activities. Among the problems that arise are poor illumination due to the use of temporarily installed electricity, the risk of accidents due to the confined workspaces, and workers avoiding work tasks because of the poor environment in tunnel. Ideas for solving these problems were developed using a value engineering (VE) process, and mechanized construction was identified as a promising solution. To verify the effectiveness of mechanized construction of a common duct in tunnels, experimental construction work was carried out, and mechanized construction was proven to directly improve the constructability and economic efficiency of common duct construction. In addition, reducing human involvement in common duct construction in tunnels is expected to improve safety, and because of the continuous concrete placement technique used, the finish and appearance of the ductwork are improved.

• Journal of the Korean GEO-environmental Society
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• v.23 no.8
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• pp.23-28
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• 2022

In Korea, 70% of the land is mountainous and structures occupy a high proportion in railway and road construction. In particular, in recent years, the construction of high-speed railways and highways for high-speed driving is rapidly increasing. At the same time, the construction of tunnels is also increasing. The number of tunnel construction cases in which long-term deformation occurs after tunnel excavation is completed is increasing. The stability of these tunnel structures depends entirely on the characteristics of the rock surrounding the tunnel excavation. In the case of pyroclastic rock, which is the subject of this study, it is generally vulnerable to weathering and has a characteristic that its strength decreases over a long period of time. Tunnel design and construction planning considering the strength characteristics of pyroclastic rocks are essential. This study analyzed the cases of over-deformation that occurred at the tunnel site in the pyroclastic section. Based on this study, a plan for tunnel design and construction management in an area where pyroclastic rock exist in the future is presented.

• 한국도로학회지:도로
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• v.16 no.3
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• pp.54-63
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• 2014

최근 터널에서 균열, 누수 등과 같은 현상이 많이 발생하고 있어 터널의 안정성 및 균열보수, 미관, 고객의 공용 중 심리적 불안감을 조성한다는 것을 쉽게 찾을 수 있다. 고속국도 제30호선 상주~안동간은 16개소/12km의 터널이 설계되어 있어 터널의 비중이 크다. 그러므로 본 연구에서는 터널 라이닝 균열발생 원인분석 및 기존사례 조사를 통하여 균열발생 최소화 방안을 검토 및 터널 라이닝의 유해한 균열방지를 위하여 공사관계자(발주처, 감리사, 시공사, 하도급사 등) 의견수렴을 통한 여러 가지 대책공법을 제안하였으며 제안공법의 효율성을 판단하기 위해 고속국도 제30호선 상주~안동간 제 8공구의 단촌 2터널, 단촌 3터널에 시험시공을 실시하여 각 공법별 균열율 및 시공성, 경제성을 고려하여 결과를 분석하고 최적의 공법을 파악, 전파하는데 그 목적이 있다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.143-144
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• 2017

본 논문은 복선터널 라이닝의 최적 계측 측점수를 산정하기 위해 복선터널 라이닝에 작용하는 하중 조건을 대칭 분포하중이 작용하는 경우로 가정하여 터널해석 시 널리 사용되는 상용 프로그램에 하중 조건을 입력시켜 터널 라이닝의 단면 위치별 변위와 응력을 산출하였다. 산출된 변위를 계측 측점 3점, 5점, 7점으로 복선터널 라이닝 역해석 프로그램에 입력시켜서 구한 응력과 변위를 비교하여 복선터널 라이닝의 최적 계측 측점수를 산정한 결과 정확도는 측점 3점이 낮고, 측점 5점과 7점이 높으며, 현장 적용성은 측점 5점이 높은 것으로 해석되어 터널 계측 실무와 일치하는 것으로 나타났다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1D
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• pp.41-49
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• 2012

Radio Frequency Identification(RFID) technology, which replace BAR CODE technology that has been widely utilizing in the field of the manufacturing industry for a long time, has been proven in the whole industries including national defense, transportation, and construction as well as manufacturing industry. Recently, with this trend, researches for adapting the RFID technology have been attempting continually centering on the architectural project in the construction industry. However, those researches are mainly focusing on the experimental utilization such as simple activity and material management. To solve these issues, this study demonstrated methodologies for adapting the RFID technology by the construction steps aiming to analyze cycle time of five types of construction process to the NATM method of tunneling work. Besides, the application of RFID technology in civil engineering work was verified by demonstrating the suggested methodology to actual sites. Therefore, it is expected that the suggested methodology will be utilized for predicting the progress rate and establishing of follow-up work plans, and the site applicability of the RFID technology will be expanded to the civil engineering projects.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.369-375
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• 2020

The section of this study is the geological vulnerable zone where groundwater leakage occurred through the tunnel barrier during excavation of the shield tunnel boring machine(TBM) for the construction of the electric power unit. Therefore, a Three D imensions(3D) numerical analysis was performed to analyze the actual situation from before construction to the time when the change in groundwater level occurred, and to reflect the surrounding ground conditions based on the observed change in groundwater level during construction. As a result of the study, the correlation between groundwater level change and tunnel construction around the site was identified. Therefore, it was similar to the measurement result of groundwater level at the target ground. The amount of groundwater discharge to the entrance of the tunnel construction was also similar to the actual measured result, and the numerical analysis method and modeling in this study were analyzed to reflect the site conditions.