• Tunnel and Underground Space
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• v.10 no.3
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• pp.418-429
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• 2000

Many Studies of tunnel and tunnelling safety have been developed continuously based on the increasing social interests in underground space since 1990's in Korea. Because the growth of population in metropolitan has been accelerated at a faster pace than the development of the cities, underground facilities have been created as a great extent in view of less land space available. In this study, a lot of types of tunnel failure were surveyed and the detail causes were studied after many cases of tunnel failure were collected. There were suggested brief countermeasure of tunnel failure through case study. An expert system was developed to predict the safety of tunnel and choose proper tunnel reinforcement system using fuzzy quantification theory and fuzzy inference rule based on tunnel information database. The comparison result between the predicted reinforcement system level and measured ones was very similar. In-situ data were obtained in three tunnel sites including subway tunnel under Han river. This system will be very helpful to make the most of in-situ data and suggest proper applicability of tunnel reinforcement system developing more resonable tunnel support method from dependance of some experienced experts for the absent of guide.

• Magazine of korean Tunnelling and Underground Space Association
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• v.23 no.3
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• pp.32-53
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• 2021

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4C
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• pp.275-282
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• 2006

Since tunnels are linear type structures that have a long extent in comparison to their excavation or inner section, tunnels must be constructed in various ground conditions. In this study, laboratory model tests and theoretical analysis on a tunnel loads are carried out in the unconsolidated ground with inclined layers for tunnel excavation. Laboratory model tests are performed with the variation in the angle of the inclined layers and tunnel depth for the model ground with inclined layers. As for the ground materials, two dimensional model ground is prepared with aluminum rods and blocks with no cohesion, which are frictional resistance free between testing apparatus walls and ground materials, by establishing the ground materials self-supporting. Moreover tunnel load equation are newly induced so that comparisons between model test results and the theoretical results are conducted as well.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2000.09a
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• pp.171-181
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• 2000

Many Studies of tunnel and tunnelling safety have been developed continuously based on the increasing social interests in underground space since 1990's in Korea. Because the growth of population in metropolitan has been accelerated at a faster pace than the development of the cities, underground facilities have been created as a great extent in view of less land space available. In this study, a lot of types of tunnel failure were surveyed and the detail causes were studied after many cases of tunnel failure were collected. There were suggested brief countermeasure of tunnel failure through case study. An expert system was developed to predict the safety of tunnel and choose proper tunnel reinforcement system using fuzzy quantification theory and fuzzy inference rule based on tunnel information database. The comparison result between the predicted reinforcement system level and measured ones was very similar. In-situ data were obtained in three tunnel sites including subway tunnel under Han river. This system will be very helpful to make the most of in-situ data and suggest proper applicability of tunnel reinforcement system developing more resonable tunnel support method from dependance of some experienced experts for the absent of guide.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.753-764
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• 2020

In this study, the plastic zone and internal earth pressure of the tunnel were calculated using the following three methods: metal plasticity to analyze the deformation of metal during plastic processing, Terzaghi's earth pressure theory from the geotechnical perspective and modified Terzaghi's earth pressure theory, and slip line theory using Mohr-Coulomb yield conditions. All three methods are two-dimensional mathematical analysis models for analyzing the plane strain conditions of isotropic materials. Using the theory of metallurgical plastics, the plastic zone and the internal earth pressure of the ground were obtained by assuming that the internal pressure acts on the tunnel, so different results were derived that did not match the actual tunnel site, where only gravity was applied. An analysis of the plasticity zone and earth pressure via the slip-line method showed that a failure line is formed in a log-spiral, which was found to be similar to the real failure line by comparing the results of previous studies. The earth pressure was calculated using a theoretical method. Terzaghi's earth pressure was calculated to be larger than the earth pressure considering the dilatancy effect.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.3
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• pp.261-268
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• 2003

Terzaghi's tunnel theory has been accepted to calculate tunnel loads conservatively in practical design until now. In this study, Terzaghi's tunnel theory was expanded to the inclined-layer ground with inclination of ground and stratification. Finally a new tunnel load equation was induced utilizing the original Terzaghi's tunnel theory and Terzaghi's tunnel theory was reviewed as well.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.3
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• pp.197-204
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• 2006

A large sectional tunnelling method using Shield TBM is expected to be popular as domestic demand of long tunnel gets growing. Although a shield tunnelling method has been recognized as prominent method in consideration of stability and applicability in shallow and poor ground, the cases of accident and constructional trouble have been often happened due to unexpected poor ground condition, or selection and use of improper shield machine. Especially, troubling cases at tunnel face are frequently occurred, so supporting pressure control of tunnel face would be the main issue for securing safer and more efficient tunnel excavation using Shield TBM. In this point, we carried out the numerical feed-back analysis to compare the ground deformation pattern with theoretical result at tunnel face.

• Explosives and Blasting
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• v.20 no.3
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• pp.49-58
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• 2002

발파공법이 소개된 이후로 계속해서 많은 우수한 발파이론이 발표되어 왔다. 그러한 이론들의 저변에 있는 궁극적인 목표는 효율의 증가와 경제성이다. 이에 본 연구는 Air-Tubes 발파공법을 소개하고 터널에서 일반발파와 비교하여 그 발파효율을 검토해 보았다 연구의 배경이 되는 곳은 산청군 시천면 내대리와 하동관 묵계리를 연결하는 2차선 국도 터널 공사 현장이며 전체 총연장은 2Km이다. 진동측정방법은 하나의 발파진동을 4개의 측정기로 측정하여 데이터분석에 사용하였다. 일반발파와 Air-Tubes의 진동측정을 4개소에서 각각 6회씩 실시하여 총 24개씩의 진동측정 데이타를 얻었고 회귀분석을 실시하여 95% 신뢰도의 발파진동 추정식을 얻었다. 시험발파 및 진동측정에 이어 매 발파마다 광파측량을 실시하여 진행장을 구하였으며 사용한 장약량은 Air-Tubes 발파시 25% 정도 적게 사용하였고 발파진동이 23% 감소하였다. 발파당 굴진장 및 Smooth blasting 발파시의 벽면의 상태는 동일하고 파쇄석의 크기는 Air-Tubes 발파시 더 작게 나타난다.

• Geotechnical Engineering
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• v.13 no.2
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• pp.169-184
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• 1997

A semi -analytical solution is derived to solve the elastic-plastic behavior of the axisymmetric tunnels in Drucker-Prager medium. Based on this analytical solution, a computer program FDAXP. is developed. Parametric studies are carried out to verify the FDAXP program, and the results were found to be satisfactory. This simple solution could be incorporated into the preliminary design, analysis of deep underground tunnel as well as tunnels with unfavourable geotechnical conditions. The program provided a useful means of checking the Drucker-Eraser model and iris associated computational algorithms in other tunnel programs.

• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.4
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• pp.361-375
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• 2007

This paper presents the results of investigation on tunnelling-induced ground surface settlement characteristics in water bearing ground using finite element (FE) stress-pore pressure coupled analysis. Fundamental interaction mechanism of ground and groundwater lowering was first examined and a number of influencing factors on the results of the coupled FE analysis were identified. A parametric study was then conducted on the influencing factors such as rock type, thickness of soil layer, permeability of shotcrete lining, among others. The results indicate that the tunneling-induced groundwater drawdown results in a deeper and wider settlement trough than without groundwater drawdown, and that the Error function approach does not yield satisfactory result in predicting a settlement profile. The results of analysis are summarized so that the relationship between the settlement and the influencing factors can be identified.