• 대한토목학회논문집
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• 제26권1A호
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• pp.163-171
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• 2006

본 논문에서는 프리스트레스를 이용한 가시설 공법(IPS)에 적용되는 띠장을 이용한 굴착면의 해석 및 설계절차에 대한 연구를 수행하였다. 받침대의 갯수에 따라 설계토압을 받는 IPS 띠장의 초기 긴장력 계산식을 유도하였다. IPS 띠장으로 구성된 빌딩 굴착면의 전산해석을 위해 띠장은 뼈대요소, 지반은 압축력 전담요소, 케이블은 인장력 전담요소를 사용하여 등분포토압 및 편토압을 받는 굴착평면의 전산해석을 수행하였다. 긴장력과 설계토압에 의한 축력과 휨모멘트를 계산하여 축응력과 휨응력을 산출하고 합성응력검토를 수행하여 굴착면의 안전성을 검토하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.7-10
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• 2008

As the land price in the downtown area increases, buildings are becoming bigger, deeper and higher. Consequently, the importance of underground construction has increased. Although construction engineers make every effort to complete underground construction without any problem, construction failures like landslides and the collapse of a retaining wall occur because of the uncertainty of the soil conditions as well as the unexpected risks of excavation work. In order to prevent potential excavation accidents, it is essential to understand the causes and impacts of such accidents. However, there are only a few examples of construction failures, which show the economic impact on accidents during excavation because of the sensibility of the information. This paper presents two cases of excavation accidents, which were investigated by construction insurance company. The compensation for the accidents paid by the insurance company was compared with the estimated costs calculated based on the estimation method for excavation accidents proposed by our previous study. The comparison results showed that the estimate calculated by our method was much less than the actual compensation because the estimate solely focused on the construction costs whereas the compensation included other external factors.

• 한국터널지하공간학회 논문집
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• 제17권4호
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• pp.499-511
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• 2015

주방식 지하구조물은 여러 개의 갱도 굴착에 의해 형성되는 격자 형태의 구조물이므로, 갱도들의 굴착순서에 따라 주방식 지하구조물의 시공성과 경제성이 좌우될 수 있다. 따라서 본 연구에서는 주방식 지하구조물의 지반조건, 굴착순서 등의 다양한 설계조건들을 고려하여 주방식 공법의 굴착공정을 검토하였다. 굴착공법으로는 발파공법을 가정하였으며, 가로 세로 병행 시공방식과 가로 세로 순차시공방식으로 구분하여 굴착공정을 검토하였다. 굴착순서에 따른 주방식 지하구조물의 안정성과 더불어 굴진면의 개수, 점보드릴의 이동거리 등에 따른 시공성을 분석한 결과, 구조적 안정성에는 큰 차이가 없으나 굴진면 운영 개소와 점보드릴의 이동거리 측면에서 가로 세로 병행 시공방법의 시공성이 상대적으로 유리한 것으로 나타났다.

• 한국건축시공학회지
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• 제8권4호
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• pp.71-77
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• 2008

Earthwork is very equipment-intensive task and researches related to automated excavation have been conducted. There is an issue to secure the safety for an automated excavating system. Therefore, this paper focuses on how to improve safety for semi- or fully-automated backhoe excavation. The primary objective of this research is to develop the core technology for automated object detection in excavation work. In order to satisfy the research objective, a diverse sensing technologies are investigated and analysed in terms of functions, durability, and reliability. The authors developed detecting algorithm for the objects using laser sensor and verified its performance by several tests. The results of this study would be the basis for developing the automated object detection system.

• 한국지반신소재학회논문집
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• 제21권4호
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• pp.21-29
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• 2022

주방식 공법(room-and-pillar method) 또는 격자형 지하공간은 굴착부를 일정한 간격으로 직교하도록 굴착하여 자연 암반을 구조체로 활용하여 공간을 형성해 나가는 공법을 말한다. 이러한 굴착은 굴착 방향과 순서에 따라 최대 변위가 발생하는 굴착 단계와 크기가 다르게 나타날 수 있다. 본 연구에서는 격자형 굴착공정의 최적 설계를 위하여 숏크리트 및 록볼트 등 지보재가 설치되는 것을 고려하여 특정 지반조건에서의 격자형 지하공간 설계 및 시공 시 안정성과 시공성을 해석적으로 검토하였다. 해석적 방법을 사용하여 지반조건을 설정하고 일정 상재하중 하에서 굴착단계와 시공 종류별로 암주 응력과 천단 변위를 확인하였다. 공간의 높이는 8m로 일반 사무실 크기보다 높게 설정하여 장비나 플랜트 시설을 감안하여 검토되었다. 또한, 숏크리트와 록볼트를 고려하여 지보재 설치에 따른 변위 제어의 정도를 검토하였다.

• Geomechanics and Engineering
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• 제34권1호
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• pp.87-102
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• 2023

The cover plate and the building loads often make the semi-covered deep excavations with existing buildings bearing asymmetric load, presenting different deformation characteristics with normal excavations, which is not absolutely clear in current studies. Based on a typical engineering, the building storeys, the basement storeys, the pile length, the existence of the cover plate (CP) and the depth of the diaphragm walls (DW) were selected as variables, and 44 groups of simulation were designed to study the influence of existing buildings and the semi-covered supporting system on the deformation of the excavations. The results showed that the maximum lateral displacement of DW, δ_hm, and the depth of δ_hm, H_m, are affected seriously by the building storeys and the basement storeys. Asymmetric structures and loading lead to certain lateral displacement of DW at the beginning of excavation, resulting in different relationships between δ_hm and excavation depth, H. The maximum surface settlement outside the pit, δ_vm, increases significantly and the location, d_m, moves away from the pit with the building storeys increases. δ_vm has a quadratic correlation with H due to the existing buildings. CP and building load will affect the style of the lateral displacement curve of DW seriously in different aspects.

• Geomechanics and Engineering
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• 제13권1호
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• pp.141-159
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• 2017

A pick cutter is a rock-cutting tool used in partial-face excavation machines such as roadheaders, and its quality is a key element influencing the excavation performance and efficiency of such machines. In this study, pick cutters with hardfacing deposits applied to a tungsten carbide insert were made with aim of increasing their durability and wear resistance. They were field-tested by being installed in a roadheader and compared with conventional pick cutters under the same excavation conditions for 24 hours. The hardfaced pick cutters showed much smaller weight loss after excavation, and therefore better excavation performance, than the conventional pick cutters. In particular, the damage to and detachment (loss) of tungsten carbide inserts was minimal in the hardfaced pick cutters. A detailed inspection using scanning electron microscope-energy dispersive X-ray spectrometry and three-dimensional X-ray computed tomography scanning revealed no macro- or micro-cracks in the pick cutters. The reason for the absence of cracks may be that the heads of pick cutters are mechanically worn after the tungsten carbide inserts have been worn and damaged. However, scanning revealed the presence of voids between tungsten carbide inserts and pick cutter heads. This discovery of voids indicates the need to improve production processes in order to guarantee a higher quality of pick cutters.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1087-1094
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• 2010

With recent growth of population and industry, urban development grows into grand scheme of excavation and construction in urban area. As the development progress advanced, the developments get large and deepen. With a progress of technology development in geotechnical engineering in Korea, most our grand scheme of projects follows great progress. On the other hand, some excavation in construction site caused direct or indirect event that affects the adjacent or surrounding structures by excavation from time to time. This event usually happens around residential and commercial area where underground tunnel, subway station, commercial building, and high-rises excavation site is, could lead great damage on economy as well as personal injury or human casualties. In order to prevent this event, the study has to be done with analysis on various events of excavation and its cause. In this paper, the research has collected the various excavation events and their causes to analyze on each site and event to define emphasis on surrounding environment.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1301-1306
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• 2009

Recently, urban excavations are one of most frequent geotechnical work according to construction of a high rise building and subway. These kind of excavation affect to a adjacent ground or structure and it can trigger various severe accidents. Generally, the ground is closer to the excavation site, the deformation become larger. In this study, special ground settlement case due to adjacent ground excavation is presented and a cause of deformation is examined by various geotechnical exploration, lab-testing and numerical analysis.

• 한국방재안전학회논문집
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• 제10권1호
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• pp.11-17
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• 2017

본 연구에서는 지반굴착공사로 인해 발생된 지반함몰 사례를 분석하고 지반함몰 발생 원인을 평가하였는데, 주요 원인으로는 지반조사의 불충분, 부정확한 지반정수, 가시설 보조공법 구조체의 결함, 보일링 및 히빙에 대한 대처 미흡, 시공시 과굴착 등으로 나타났다. 그리고 지반함몰 발생원인 분석을 통해 지반굴착공사 위험요소를 도출하였는데, 지반조사, 굴착공법 선정, 구조물 해석, 계측계획, 굴착공법 시공, 지하수위 변화, 계측 수행, 자연재해, 시공관리 등이 지반함몰을 예방하기 위해 고려해야할 위험요소로 도출되었다. 또한, 도출된 위험요소에 대한 중요도를 평가하고, 신뢰도를 높이기 위해 국내 전문가들을 대상으로 설문조사를 수행하였고, 카이제곱(${\chi}^2$) 검정 방법 통해 설문조사 응답자의 직업군, 업무종사기간, 업무현장종류 등과 설문조사결과가 유의한 수준인지에 대해 검정을 수행하였다.