• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1095-1102
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• 2010

본 연구에서는 펄스 방전 기술에 의해 확공된 앵커의 인발 거동에 대한 수치해석을 수행하였다. 펄스 방전 현상을 등가의 폭발 현상으로 모델링하여 점성토와 사질토 지반에 대한 확공해석을 수행하였으며 이를 통해 펄스 방전에 의해 개량된 지반 조건을 구현하였다. 확공된 지반에 대해 설치된 압축형 그라우트 앵커의 인발 거동을 시뮬레이션하여 인발력-인발변위 곡선을 산정하였다. 해석 결과, 점성토의 경우에는 확공 정도가 인발 거동과 밀접한 관련을 갖는 반면, 사질토의 경우에는 확공 정도 이외의 추가적인 증가 요인이 확인되는 것으로 나타났으며 펄스 방전 기술이 사질토 지반의 다짐을 통해 앵커의 인발력을 증가시키는 것으로 판단되었다.

• 한국지반공학회논문집
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• 제27권12호
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• pp.27-37
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• 2011

강한 지진 발생 시 뒤채움내의 과잉간극수압의 증가에 의해 지반이 액상화 되었을 때, 주변의 액상화 지반보다 작은 단위중량을 가진 지중 매설구조물은 부상하는 현상이 발생한다. 뒤채움에서의 과잉간극수압의 증가와 지중 매설 구조물 부상량의 관계를 설명하기 위해 동적 원심모형 실험을 수행되었다. 본 연구에서는, 매설구조물의 부상현상에 영향을 미치는 요인으로써 직접요인과 간접요인이 실험에 고려되었다. 이러한 요인들 중에, 과잉간극수압비의 증가에 영향을 주는 중요한 요인은 직접요인으로써의 지하수위, 뒤채움의 상대밀도, 그리고 입력 지진가속도의 크기이다. 그리고 이 요인들은 지중 매설구조물의 부상량에도 크게 영향을 주는 것으로 나타났다.

• 한국항해항만학회지
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• 제29권6호
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• pp.561-566
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• 2005

본 연구에서는 풍하중 설계 기준에 따른 50톤급 컨테이너 크레인의 안정성을 비교${\cdot}$분석하였다. '항만시설장비기준 /크레인강 구조부분 설계 기준(KS A 1627)'과 건설교통부의 '건축물하중기준'에 의거한 풍하중이 산정되었으며, 이리한 풍하중이 컨테이너 크레인에 작용할때, 컨테이너 크레인의 각 지지점에서 발생돠는 반력을 분석함으로써 구조적 안정성을 비교${\cdot}$평가하였다. 연구결과. 컨테이너 크레인의 설계 풍하중 산정 시 설계풍속의 명확한 정의가 필요하고, 컨테이너 크레인의 구조 안정성 분석을 위하여 인장력 평가와 지반 안정성을 고려하기 위한 최대 압축력 검토의 필요성을 확인하였다.

• 한국농공학회논문집
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• 제63권3호
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• pp.27-33
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• 2021

Reclaimed land was mainly used as agricultural land for rice production. As a higher value-added business in the agriculture has recently been activated, green houses are being constructed. In case of green house construction on the reclaimed land, it is generally soft ground with high soil water content, so it is important to design the foundation for greenhouse construction. The object of this study, a pull-out test was conducted to derive the base line data of the wooden pile foundation when constructing a green house. To reproduce the actual site, 30% of soil saturation and 70% of soil saturation were created in the soil box. Groove number and depth were set as design factors of the wooden pile, and a pull-out test was conducted. As a result of the test, pull resistance increased as the number of grooves increased, pull-out resistance according to groove depth was different according to soil saturation. Also, after the experiment, we want to compare the set-up effects over time.

• Geomechanics and Engineering
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• 제24권6호
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• pp.559-572
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• 2021

This research presents the monitoring results and their interpretation on load sharing of the pile foundation during the construction of a high-rise (124 m in height) building in Bangkok, in soft clayey ground. Axial forces in several piles, pore water pressure and earth pressures beneath the raft in a tributary area were monitored through the construction period of the building. The raft of the pile foundation in soft clayey ground can share the load up to 10-20% even though the foundation was designed using the conventional approach in which the raft resistance is ignored. The benefit from the return of ground water table as the uplift pressure is recognized. A series of parametric study by 3D-FEA were carried out. The potential of utilizing the piled raft system for the high-rise building with underground basement in soft clayey ground was preliminarily confirmed.

• 산업기술연구
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• 제26권A호
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• pp.109-117
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• 2006

This study is an numerical study of predicting the behavior of anchor embedded in weathered rocks, subjected to uplift loads, about ultimate pullout capacity and the failure mechanism. Factors influencing the behavior of anchors were investigated by reviewing the data about in-situ anchor tests performing numerical modelling with changing the bondage length of anchor, diameter of anchor body and diameter of tenden, and by Correlations between those factors were evaluated to apply them to predict the behavior of anchors. As results of numerical analysis, a linear relationship between bondage length, diameter of anchor body and diameter of tenden with ultimate pullout capacity was obtained on the one hand, from the result of numerical analysis changing the Young's modulus of weathered rock, this parameter was found to inflence to load-displacement and ultimate pullout capacity within the range of 10%, which was mot so significant to affect.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.745-751
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• 2009

The anchor is used extensively for a cutting slope, an earth retaining wall, an uplift resistance of sub-structures and so on at civil engineering projects and is classified by aim in use, tendon material, and ground/tension fixing type. It can be distinguished extensively into friction type, bearing type, and complex type by ground fixing type. Generally, bond length of friction type anchor has application to 3~10m depending on the friction-resistance characteristics. In this study, 'DEW(double enlargement wedge) bearing type anchor' of new concept is devised. The bond length is about 0.6~0.8m. It can be used on the ground to have the strength characteristics above it of weathered rock. There are merits which are 'period reduction' and 'cost saving' through the minimum of the boring length. In addition, it is so called environmentally friendly Methods because it can reduce the quantity of carbon dioxide through the reducing drilling machine operation time.

• Smart Structures and Systems
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• 제26권3호
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• pp.277-290
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• 2020

Disasters, including earthquakes and landslides, have enormous economic and social losses besides their impact on environmental disruption. Iran, and particularly its Western part, is known as an earthquake susceptible area due to numerous strong ground motions. Studying ecological changes due to climate change can improve the public and expert sector's awareness and response to future disastrous events. Synthetic Aperture Radar (SAR) data and Interferometric Synthetic Aperture Radar (InSAR) technologies are appropriate tools for modeling and surface deformation modeling. This paper proposes an efficient approach to detect ground deformation changes using Sentinel-1A. The focal point of this research is to map the ground surface deformation modeling is presented using InSAR technology over Sarpol-e Zahab on 25^th November 2018 as a study case. For surface deformation modeling and detection of the ground movement due to earthquake SARPROZ in MATLAB programming language is used and discussed. Results show that there is a general ground movement due to the Sarpol-e Zahab earthquake between -7 millimeter to +18 millimeter in the study area. This research verified previous researches on the advanced image analysis techniques employed for mapping ground movement, where InSAR provides a reliable tool for assisting engineers and the decision-maker in choosing proper policies in a time of disasters. Based on the result, 574 out of 682 damaged buildings and infrastructures due to the 2017 Sarpol-e Zahab earthquake have moved from -2 to +17 mm due to the 2018 earthquake with a magnitude of 6.3 Richter. Results show that mountainous areas have suffered land subsidence, where urban areas had land uplift.

• 지질공학
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• 제33권4호
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• pp.689-699
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• 2023

Assessing ground stability is critical to the construction of underground transportation infrastructure. Surface displacement is a key indicator of ground stability, and can be measured using interferometric synthetic aperture radar (InSAR). This study measured time-series surface displacement using permanent scatterer InSAR applied to Sentinel-1 SAR images acquired from January 2017 to June 2023 for the area around a deep underground expressway under construction to connect Mandeok-dong and Centum City in Busan, South Korea. Regions of seasonal subsidence and uplift were identified, as were regions with severe subsidence after summer 2022. To evaluate stability of the ground in the construction area, the mean displacement velocity, final surface displacement, cumulative surface displacement, and difference between minimum and maximum surface displacement were analyzed. Considering the time-series surface displacement characteristics of the study area, the difference between minimum and maximum surface displacement since June 2022 was found to be the most suitable parameter for evaluating ground stability. The results identified highly unstable ground in the construction area as being to the north of the mid-lower reaches of the Oncheon-cheon River and to the west of the Suyeong River at the point where both rivers meet, with the difference between minimum and maximum surface displacement of 40~60 mm.

• 한국지반신소재학회논문집
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• 제17권4호
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• pp.73-79
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• 2018

서해안과 남해안 그리고, 하천유역에는 연약지반을 개량하여 산업시설 공간과 농경지 확보를 위해 토목섬유매트 활용이 많아지고 있다. 광대한 연약한 지반을 개량하기 위한 초기단계로 장비 진입을 위해 토목섬유매트를 포설하고 접합하여 넓은 지반의 지지력을 증대시킨다. 토목섬유매트 봉합강도는 원단 인장강도의 50% 정도만 힘을 발휘하고 있어 장비주행성에 융기와 침하 등 지지력 저하의 문제들이 발생한다. 본 연구는 여러 가지 토목섬유매트 봉합기술들을 분석하고 각 방법들의 인장강도를 비교분석하였다. 또한 토목섬유매트의 봉합강도를 증가시켰을 때, 상재하중에 의한 지반내의 응력증가분이 감소하는 경향을 수치해석으로 확인하였다. 봉합강도를 60, 70, 80%으로 향상시켰을 때 토목섬유에 의한 지반의 지지력 증가를 확인할 수 있었다.