• 수산해양교육연구
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• 제25권1호
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• pp.260-273
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• 2013

This study aims to reflect experts' opinions in analyzing a design thinking as foundation of multidisciplinary education. For this purpose, a delphi survey was conducted with 20 experts in three sessions from May 1 to June 25, 2012. To analyze the collected data, descriptive statistics, including frequency, percentage, the mean, and standard deviation were implemented, and internal reliability test on the survey instrument was carried out for statistical processing. The main results are as follows : First, the delphi analysis on intuitive thinking of design thinking suggested 7 items(to pursue the possibility of outside, to pursue the possibility of applying new forms of technology, content planning, facing a complex real-world phenomena etc.). Second, the delphi analysis on logical thinking of design thinking suggested 7 items(executed repeatedly, reasoning and verification, artificial intelligence, a decision support system etc.) Third, the delphi analysis on subjective thinking of design thinking suggested 9 items(user experience measuring, user satisfaction ratings, user requirements analysis, user interface design, behavioral responses of the human etc.). Fourth, the delphi analysis on objective information of design thinking suggested 8 items(information management system, simulation, production process, information exchange and sharing etc.). According to the results of the delphi analysis, design thinking can be seen as the foundation of multidisciplinary education. Suggestions were made for discussion about the main results and further researches.

• Structural Engineering and Mechanics
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• 제50권3호
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• pp.257-273
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• 2014

This paper introduces a novel optimization technique based on gravitational search algorithm (GSA) for numerical optimization and multi-objective optimization of foundation. In the proposed method, a chaotic time varying system is applied into the position updating equation to increase the global exploration ability and accurate local exploitation of the original algorithm. The new algorithm called global-local GSA (GLGSA) is applied for optimization of some well-known mathematical benchmark functions as well as two design examples of spread foundation. In the foundation optimization, two objective functions include total cost and $CO_2$ emissions of the foundation subjected to geotechnical and structural requirements are considered. From environmental point of view, minimization of embedded $CO_2$ emissions that quantifies the total amount of carbon dioxide emissions resulting from the use of materials seems necessary to include in the design criteria. The experimental results demonstrate that, the proposed GLGSA remarkably improves the accuracy, stability and efficiency of the original algorithm.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.124-143
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• 2010

Cofferdam is a temporary levee or dam structure built by using sheet pile or earth materials to prevent water infiltration during construction work of bridge, dam, harbour dock, or hydraulic structures in the river. In this regard, it is required to secure cutoff ability for dry work and workability for rapid installation and removal of the temporary dam or levee structures. In this paper, case studies for design and construction of cofferdam were performed, and water diversion method was briefed with some examples of cofferdam type as well. For the case study details of design and construction were reviewed based on cofferdams under construction related to 16 submerged weirs of "The 4-river restoration project" and dam type cofferdam respectively. From the review, it was known that the method for changing the water flow is selected based on the data from geological and geo-hydraulic site investigation in order to mitigate environmental effects by making sure if the design cross-sectional area of flow and maximum working days are sufficiently guaranteed. Finally, the primary findings and main conclusion derived are summarized that determination of applicable type of cofferdam should be checked by case study and meet design requirements such as water inflow control, constructability.

• 한국지반공학회지:지반
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• 제12권3호
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• pp.73-82
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• 1996

하중과 저항계수 설계론을 채택하는 극한상태 설계 법이 지반공학분야에도 세계적인 추세로 적용되고 있다. 현재의 허용응력설계법은 논란을 거듭하면서 극한상태 설계법으로 교체되리라 전망된다. 최근에 북미와 유럽에서 시방서로 발간되면서 본격적으로 지반공학설계분야에 관심이 되고 있다. 이러한 세계적인 설계이론을 적절히 비교분석함은 장차 한국의 건설여건에 맞도록 적용하는데 기본요건이라 하겠다. 본 논문에서는 극한상태설계 법을 검토하고 말뚝설계에 하중과 저항계수 설계론을 적용하여 분석하고자 한다.

• 한국지진공학회논문집
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• 제1권3호
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• pp.1-10
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• 1997

구조물 동적거동이 지반과 기초 특성에 따라 영향을 받는다는 것은 인식되었지만, 구조물 내진설계를 위한 설계규준이 지반의 본질적인 복잡성과 기초-지반체계에 대한 체계적인 연구부족으로 지반특성을 부분적으로만 반영하고 있어 불안전하거나 너무 안전한 결과를 초래한다. 이 연구에서는 전단파속도, 지반깊이, 기초 근입깊이 및 말뚝기초의 영향을 평가하여 구조물 내진해석을 위한 기초-지반체계의 운동학적 상호작용 영향을 고찰하였으며, 지반과 기초 특성을 고려한 합리적 내진해석을 위해 지반체계에 대한 수정된 분류기준을 제안하였다. 말뚝기초를 포함한 중형이나 대형 묻힌기초의 경우, 지초-지반체계의 운동학적 상호작용 영향을 고려하기 위해서는 기토밑 지반깊이를 최소한 60m 까지 고려해야하고, 말뚝유무에 관계없이 기초-지반체계의 회전운동도 구조물 내진해석에 포함되어야 한다.

• 한국지반신소재학회논문집
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• 제22권1호
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• pp.25-37
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• 2023

국내 중소규모 건축구조물 기초에 적용 사례가 없는 고밀도 폴리에틸렌 신소재 재료로 구성된 셀룰러 기초 매트리스가 건축구조물 기초 공법의 대안으로 정착되기 위해서는 국내 지반 및 현장 조건에 맞게 개량된 공법 개발 및 검증이 필요하다. 본 연구를 통해서 셀룰러 기초 매트리스의 기초적인 설계 및 시공 방법을 제시하였다. 셀룰러 기초 매트리스의 기초보강효과는 연약지반 대상으로 안정성 평가와 검증이 되어야 하기에 국내 중소규모 건축구조물 기초에 적용 실적이 풍부한 소일백공법과 성능 비교 평가를 수행하였다. 매트리스 보강 후 평판재하시험 결과, 원지반과 비교하여 침하량은 38.4% 감소, 지지력은 159% 증가하였으며, 소일백공법과는 동일한 지반보강효과 및 지반안정성을 확인하였다.

• 한국산학기술학회논문지
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• 제20권4호
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• pp.606-612
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• 2019

도심지 도로하부에서 발생하는 지반침하 및 싱크홀의 주요 원인은 하수관로 기초 및 관로뒤채움재의 부적절한 다짐 등이다. 이로 인해 하수관거의 이음부 파손 및 접합 불량, 관의 파손 및 균열 등 많은 문제점이 발생하고 있다. 이를 해결하기 위해 하수관거 기초와 관련된 받침계수 및 굴착 깊이에 따른 안전율을 평가하였다. 강성관용 기초로는 쇄석기초, 버림 콘크리트 기초, 그리고 최근 새로 개발된 현장조립식 경량플라스틱 기초를 이용하였고, 뒤채움재는 현장발생토사(사질토 및 점성토), 현장발생토사를 재활용한 유동성뒤채움 등을 적용하였다. 굴착 깊이 및 하수관 기초별 안전율을 평가하기 위하여 하중 계수 및 받침계수 등을 고려한 설계하중을 평가하였다. 받침계수는 쇄석기초 0.377, 버림 콘크리트 기초($180^{\circ}$ 및 $120^{\circ}$) 0.243 및 0.220, 경량 플라스틱 기초와 유동성 뒤채움재는 0.231로 적용하였다. 전체적으로 쇄석기초 사용 시 안전율이 작게 나왔고, 받침각 $180^{\circ}$ 버림 콘크리트 기초 사용 시 안전율이 가장 크게 나타났다. 또한, 경량 플라스틱 기초와 유동성 뒤채움재의 조합을 이용할 경우 받침각 $120^{\circ}$ 버림 콘크리트 기초보다 안전율이 크게 나타났다. 이는 새로 개발된 재활용 경량 플라스틱 기초가 강성관의 또 다른 대안 기초로 활용이 가능함을 의미한다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1990년도 가을 학술발표회 논문집
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• pp.85-90
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• 1990

Current steel pile foundation design is bared an WSD, but the reliability based design method is more rational than the WSD. For this reason, this study proposes a reliability Index of the pile foundation by LFD which is most common type of pile foundation, and also proposes the theoretical bases of nominal safety factors of stability analysis by introducing the reliability theory. The measured bearing capacity data are analyzed to the descriptive statistics and classified into the four models of uncorrelated -normal(UNNO), uncorrelated -nonnormal(UNNN), correlated -normal(CONO), and correlated nonnormal (CONN). This study presents the comparisons of reliability index and check points using the AFSOM with respect to the four models as well as BASIC program.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.145-156
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• 2009

Large diameter bored pile was selected as the foundation type for Taipei 101. The pile construction method and specific construction procedures were determined based on the results of trial installation and pile load tests. The baseline for foundation design was established using the friction versus depth characteristics of each ground layer obtained from the pile load tests. As the ground profile and depth to the top of rock formation varied significantly on this site, the pile length, bearing capacity and settlement for single pile were analyzed using the information interpreted from adjacent boreholes. The post grouting at pile tip was mandatory for pile construction. Nevertheless, it was treated as a measure reducing the influence of construction uncertainties and providing extra safety for the foundation system.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.59-62
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• 2008

Scour vulnerability evaluation for shallow foundations was performed to assure bridge safety against scour in the national capital region. The case studies for 26 shallow foundations consisted of site investigation including boring test, bridge scour analysis for the design flood, bearing capacity evaluation of the bridge foundation before and after scour, and comprehensive evaluation of bridge scour vulnerability. Bridge scour vulnerability was determined based on the interdisciplinary concept considering predicted scour depth for the design floods and bearing capacity of foundation as well as dimensions of foundation. Nine of 26 shallow foundations showed the potential future vulnerability to scour with significant decrease in the bearing capacity of foundations due to scour and the remaining 17 were expected to maintain their stability against scour.