• 한국터널지하공간학회 논문집
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• 제18권6호
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• pp.569-579
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• 2016

국내 터널 갱구사면에 안정성을 확보하기 위한 사면보강은 앵커, 쏘일네일 및 록볼트 등을 이용한 다양한 공법이 사용되고 있다. 갱구 사면보강공법 및 보강재 배치, 보강재 길이 등을 선정하기 위해서는 시행착오법 등 시간이 많이 소요되기도 하며, 최적조건의 상태가 선정되었는지에 대한 검증이 쉽지 않은 경우도 발생한다. 본 연구에서는 FLAC3D 프로그램에 내장된 FISH 언어를 사용해서, 차분진화 알고리즘(DEA)을 적용한 최적화기법을 개발하였다. 갱구사면 보강공법 중에 쏘일네일링 공법에 대한 데이터베이스를 구축한 후, FLAC3D 해석을 통한 안전율 기반의 최적보강배치 계획을 선정할 수 있도록 하였다. 수치해석 결과, 완전조합(FC)에 비해서 DEA 기반의 최적화기법이 해석회수가 8배 정도 감소함을 확인하였다. 갱구 사면보강 설계 시 개발된 시스템을 활용하면, 최적보강배치 계획을 상대적으로 쉽게 선정할 수 있을 것으로 기대된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.634-643
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• 2006

This study was intended to develop a high reliable technique by statistically processing on-site data with a general linear model, providing the basic data for construction, analysis of stability and establishment of maintenance measures for tunnel portal slopes in the future. This study evaluated the stability of a tunnel portal slope using a quantified technique, which is based on a general linear model. The important scores of each independent variable were allocated by using the ranges of the quantified values, based on the predicted coefficient of regression and the scores for categories of each independent variable were allocated so that those are equally spaced. The quantification model obtained from the results of evaluating the total data used for the quantification process provided precise results. In addition, it is expected that a more detail subdivision of response variables and sufficient data would produce a better stability evaluation standard.

• Steel and Composite Structures
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• 제24권3호
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• pp.277-285
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• 2017

Single-storey industrial buildings are one of the most often type of structures built among various skeletal framed steel constructions. These metallic buildings offer an exceptional opportunity to minimise the material employed, contributing to a more sustainable construction. In particular, the mansard portal frame is a typology made up of broken beams that involves different lengths and discontinuous slopes. This study aims the weight reduction of the standard mansard portal frame with design purposes by means of varying four parameters: the kink position, the eaves-apex slope, the span and the columns height. In this work, we suggest some guidelines that can improve the economical competitive capabilities of their structural design. In all the cases analysed, the joints of the portal frame are placed over the theoretical non-funicular shape to uniform loads. This allows reducing the bending moment and the shear force, but increasing the axial force. In addition, the performance of mansard and typical pitched portal frames submitted to the same boundary conditions is compared in terms of efficiency in the use of steel. In the large majority of the cases, mansard typologies are lighter than the common pitched frames and, hence, more economical.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.493-498
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• 2003

In case of slope failure by planted protection is constructed on the slope according to of the choice trend of a recently environmental-friendly countermeasure, there has a limitation about diagnosis and preparation of measure. Also, collapse of tunnel pithead department slope has maximum in construction and countermeasure method of construction choice unlike cut-slope. In this study, analyzed inside circumstance of slope using geophysical exploration for stability analysis and countermeasure inside presentation of tunnel pithead department slope which collapse happens. geophysical exploration used dipole(Dipole-Dipole) method that is based to distribution principle does specific resistance, goes side by side with on-the-spot observation and draws base strength parameter and executed stability analysis, and presented stabilization countermeasure inside of collapse slope on this. I wish to conduce in development and research for use technical development of geophysical exploration technique hereafter by executing geophysical exploration in road collapse spot applying through this study.

• 한국안전학회지
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• 제23권1호
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• pp.28-34
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• 2008

The corrugated steel plate structures is applied to the construction of mountain tunnel portal part with shallow depth, the tunnel on the outskirts of urban areas and ecology move passage. In this study, A finite element method is used for research the behavior of corrugated steel plate structures due to construction position under declinating earth pressure and excavation depth. A finite element method were performed varying construction position(10, 15, 20 and 25m) from slope and excavation depth from surface. The hoop thrust and moment, displacement of corrugated steel plate subjected to construction position and excavation depth is determined from a finite element method. From results of finite element method, it was found that the increase of thrust and the decrease of displacement as the amount of distance increase from slope with construction position. But the thrust and moment, displacement has not different value with excavation depth.

• Geomechanics and Engineering
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• 제32권1호
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• pp.111-123
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• 2023

The slope of an open cut tunnel is located above the exit of the Leijia tunnel on the Changgan high-speed railway. During the excavation of the open cut tunnel foundation pit, the slope slipped twice, a large landslide of 92500 m³ formed. The landslide body and unstable slope body not only caused the foundation pit of the open cut tunnel to be buried and the anchor piles to be damaged but also directly threatened the operational safety of the later high-speed railway. Therefore, to study the stability change in the slope of the open cut tunnel under heavy rain and excavation conditions, a 3D numerical calculation model of the slope is carried out by Midas GTS software, the deformation mechanism is analyzed, anti-sliding measures are proposed, and the effectiveness of the anti-sliding measures is analyzed according to the field monitoring results. The results show that when rainfall occurs, rainwater collects in the open cut tunnel area, resulting in a transient saturation zone on the slope on the right side of the open cut tunnel, which reduces the shear strength of the slope soil; the excavation at the slope toe reduces the anti-sliding capacity of the slope toe. Under the combined action of excavation and rainfall, when the soil above the top of the anchor pile is excavated, two potential sliding surfaces are bounded by the top of the excavation area, and the shear outlet is located at the top of the anchor pile. After the excavation of the open cut tunnel, the potential sliding surface is mainly concentrated at the lower part of the downhill area, and the shear outlet moves down to the bottom of the open cut tunnel. Based on the deformation characteristics and the failure mechanism of the landslides, comprehensive control measures, including interim emergency mitigation measures and long-term mitigation measures, are proposed. The field monitoring results further verify the accuracy of the anti-sliding mechanism analysis and the effectiveness of anti-sliding measures.

• 대한핵의학회지
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• 제25권2호
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• pp.200-206
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• 1991

Arterial fraction of total hepatic blood flow was estimated by a new method, slope method, on radionuclid angiogram using $^{99m}Tc-DISIDA$ and was compared with that from $^{99m}Tc-Phytate$ radionuclide angiogram. This study included 11 of normal subjects, 37 of intermediate group with various liver diseases, and 25 patients with liver cirrhosis. We analyzed the datas with slope method from radionuclide angiograms and the results were compared with hepatic arterial fractions from uptake method, introduced by Lee et al. at 1986. The hepatic arterial fractions from radionuclide angiograms using $^{99m}Tc-DISIDA$ and $^{99m}Tc-Phytate$ were $0.32{\pm}0.09\;and\;0.31{\pm}0.11$ respectively in normal subjects, and $0.75{\pm}0.18\;and\;0.77{\pm}0.21$ respectively in patients with liver cirrhosis. The hepatic arterial fractions by the slope method was well correlated with those of the uptake method on $^{99m}Tc-DISIDA$ scan. There was high correlation between the hepatic arterial fractions from $^{99m}Tc-DISIDA$ and $^{99m}Tc-Phytate$ scans. Hepatic arterial fraction estimated by the slope method is a useful index for the diagnosis of liver cirrhosis and the evaluation of status of portal hypertension.

• 지질공학
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• 제19권3호
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• pp.401-408
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• 2009

단양과 가곡을 잇는 기존 구국도 59호선에는 35개소의 절토사면이 존재한다. 본 구간은 도로선형이 복잡하고, 폭이 협소하며, 2002년과 2006년 집중강우의 영향으로 절토사면 붕괴, 산사태, 도로침하 현상이 발생되는 등 위험성이 높아 신설국도를 계획하게 되었다. 2006년 12월 신설국도 공사 중 터널입구부사면이 붕괴되었으며, 상부에 존재하는 군도의 중앙선을 따라 인장균열이 발생되었다. 붕괴원인 파악 및 대책공법 제시를 위해서 면밀한 현장조사 및 인장균열에 대한 모니터링을 실시하였고, 스테레오투영망 해석, 한계평형해석, 유한차분해석을 수행하였다.

• 한국암반공학회:학술대회논문집
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• 한국암반공학회 2007년도 특별심포지엄 논문집
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• pp.63-79
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• 2007

Several remedial works were attempted to stabilize the collapsed area of the inlet slopes of diversion tunnel, but prevention of any further movement was being only carried out at beginning stage by filling the area with aggregates and rock debris, after several cracks had been initiated and developed around the area. The extra specialty developed folding zone is consisted with highly weathered Greywacke and Black shale. The suggested solution is to improve the properties of the rock mass of failed area by choosing the optimum level of reinforcement through the increment of slope rock support design so as to control the movement of slopes during the re-excavation. The Bakun hydroelectric project includes the construction of a hydroelectric power plant with an installed capacity of 2,520MW and a power transmission system connecting to the existing transmission networks in Sarawak and Western Malaysia. The power station will consist of a 210m height Concrete Faced Rockfill Dam. During the construction of the dam and the power facilities the Balui River has to be diverted of the tunnels is 12m and the tunnel width is 16m at the portal area. This paper describes the stability analysis and design methods for the open cut rock slopes in the inlet area of the diversion tunnels. The geotechnical parameters employed in stability calculations were given as a function of four defined Rock Mass Type (RMT) which were based on RMR system from Bieniawski. The stability calculations procedure of the rock slopes are divided into two stages. In the first stage, it is calculated for the stability of each "global" slope without any rock support and shotcrete system. In the second stage, it is calculated for each "local" slope stability with berms and supported with rock bolts and shotcrete. The monitoring instrumentation was performed continuously and some of the design modification was carried out in order to increase the safety of failed area based on the unforeseen geological risks during the open cut excavation.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.573-576
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• 2008

절토사면 및 천심도 터널의 경우 불연속면을 따른 블록의 미끄러짐 및 회전 등이 안정성에 큰 영향을 미친다. 국도나 지방도 등을 확장 공사함에 따라 산악이 많은 우리나라 지형의 특성상 절토사면이 많이 발생하게 되고, 경우에 따라서는 이러한 절토사면에 터널이 위치하게 된다. 이런 상황의 터널갱구부 및 인접한 절토사면부에서 붕괴 및 균열이 빈번하게 발생되고 있다. 본 연구에서는 대절토사면과 인접한 터널갱구부에 대하여 편토압이 균열의 주원인인지를 결정하기 위하여 변위 및 응력 패턴을 분석한 사례연구를 제시하였다. 조사대상지역은 울진군에 위치한 터널굴진 현장이고, 붕괴는 터널갱구부와 인접한 절토사면부에서 발생하였으며 터널갱구부 상단의 숏크리트 타설지역에서 다수의 균열이 관찰되었다. 언급한 터널갱구부의 변위 및 응력패턴을 모사하기 위하여 유한차분법에 근거한 플랙을 사용하였으며, 세밀한 수치해석을 위해 편재절리모델을 도입하였다. 마지막으로, 터널갱구부의 균열에 영향을 미친 주원인에 대한 고찰을 다루었다.