• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.241-248
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• 2003

In August 2002, side wall of OO tunnel, at the Bonghwa, Kungbuk province, Korea, was collapsed by abruptly applied heavy soil and water pressure to side wall from a inclined shaft when there was a heavy rain. These days, Inclined shaft is used for the purpose of reducing construction time, using ventilation system, using the out of carrying equipment and mucking when we construct tunnel in the world. Recently constructed tunnel has the source of inclined shafts, but the more time elapse, we lose the source of the inclined shaft such as exact position, condition, and the fact that whether inclined shaft is exist or not. Therefore, this study inspected the interior's appearance, analyzed structure to evaluate the reason of collapsing side wall and this study also performed the repairing work. Finally, we show improving maintenance method to prevent that similar accident that might be happened.

• 한국농공학회논문집
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• 제58권3호
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• pp.91-100
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• 2016

Recently, lots of damages have been lost because large magnitude earthquakes were occurred in the world. It has been increased the number of earthquakes in Korea. It needs improvement required for the repair of deteriorated reservoirs, reinforcement and raised reservoir coping with climate change and earthquake. This study aims to investigate the seismic behavior of deterioration reservoir levee using dynamic centrifugal model test. Therefore, two case tests in centrifugal field of 60 g, the result has provided the influence on the acceleration response, displacement, settlement and the pore water pressure of the reservoir with earthquakes. From the results larger displacement and acceleration response at the front side of reservoir embankment with poor-fabricated core in seismic condition may degrade overall stability. Reasonable reinforcement method of the raised reservoir embankment is required for ensuring long-term stability on earthquake.

• Advances in concrete construction
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• 제9권1호
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• pp.93-102
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• 2020

In this study, we examined the relationship among the rheological properties, workability, and extrudability in the construction of concrete structures using additive manufacturing. We altered the component materials (binder type, water-binder (W/B) ratio, sand ratio) to assess their effect on the rheological properties experimentally. The results indicated that the W/B and sand ratios had the largest effect on the rheological properties. In particular, when the sand ratio increased, it indicated that adjusting the sand ratio would facilitate control over the rheological properties. Additionally, we compared the rheological properties with the results of a traditional workability evaluation, namely the table flow test. This indicated the possibility of inferring the rheological properties by using traditional methods. Finally, we evaluated extrusion quantity according to table flow. The extrusion rate was 350 g/s for a flow of 210 mm and 170 g/s for a flow of 130 mm, indicating that extrusion rate increased as flow increased; however, we concluded that a flow standard of approximately 140-160 mm is suitable for controlling the actual extrusion quantity and rate.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1213-1216
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• 2010

Developable areas nearby metropolitan areas, which has high the density of population are limited by highly industrialized. In recent, the redeveloping plans for the finished industrial and resident areas are pushing to resolve this problems. Getting to the exact properties for reclaimed wastes is very important to reuse of landfill. Also, a strategy for how to deal with follow-up measures have to based on the waste characteristics. A lot of environmental problems have been happened in finished waste landfill such as a nasty smell by seepage, pollution of surface and ground water, a poisonous gas and soil contamination. The environment pollution in waste landfill have been studied by many researchers. The goal of this study is estimate the effects for the ground properties with the environmental properties of waste in finished landfill. As the results, the chemical characteristics of seepage in landfill may effect directly or indirectly to capping layer. Therefore, sustainable researches are needed to develop a secure landfill over the long term.

• 한국시스템다이내믹스연구
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• 제4권2호
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• pp.71-94
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• 2003

The purpose of this dissertation is to build a development density control model and estimate optimum developmental density level for a sustainable urban growth management. To develop the model, system dynamics modeling approach was used. The model was developed to analyze how urban growth, transition, and decay occur depending on the interaction among population, houses, industry structure, land and urban infrastructure such as road, water supply, and sewage treatment facilities. The model was applied to Anyang city to estimate optimum density level. Extensive computer simulation was conducted to find out the maximum numbers of population, industry structure, houses, and cars that can be adequately sustained with the current Anyang city's infrastructure capacity. The computer simulation result shows that the city is overpopulated by some 90,000 people. It nab analyzed that 20％ increase of existing capacity of urban infrastructure is necessary to support current population of Anyang city. To reduce the population to the adequate level whereby the current urban infrastructure can sustain, the current city regulation on floor area ratio needs be strengthened at least 20％ to 35%.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.474-479
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• 2011

With Beijing's success in bidding for the 2008 Olympic Games, the increasing demand for infrastructure development and reduced public sector funding capacity has created a significant funding gap which calls for alternative project delivery methods such as Public-Private Partnership (PPP). Although the exploration of infrastructure projects using PPP model have been practiced since the late 80s, the $560 million National Stadium which served as the main venue for the Olympic Games is the first stadium project in China to be delivered under PPP operation. The project is generally considered successful despite the concession transfer in 2009 with concern of better serving the public interest. Compared to other infrastructure projects such as transportation, waste management and water management, the development of major sports facilities for mega-sports events with PPP has its own unique features and is subject to different major risks. This research identifies and analyzes critical risks in the implementation of PPP in major sports facility development through case study of the National Stadium project. A questionnaire survey and several interviews are conducted to solicit expert opinions from experienced practitioners. The purpose is to provide additional insights in risk management strategies and opportunities in China's PPP implementations in major sports facilities for policy makers and private sectors involved with investment decisions in future similar infrastructure development.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2011년도 학술발표회
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• pp.7-7
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• 2011

On March 11 in 2011, off the Pacific coast of Tohokua huge earthquake of Magnitude 9.0 occurred. This presentation reports the earthquake, the ensuing tsunami and the devastating damages caused by them. The epicenter was approximately 72 km east of the Oshika Peninsula of Tohoku, with the hypo-center at an underwater depth of approximately 32 km. Owing to this earthquake, strong quakes were observed in eastern Japan with the levels 6 and 7 on the Japanese scale. The earthquake triggered extremely destructive tsunami wave, which attacked the very wide range of eastern Japan coast. The earthquake and ensuing tsunami caused severe damage to levees and embankment along the coasts and rivers. Those water-related damages are reported in this presentation. The Fukushima No. 1 Nuclear Power Plant was also damaged by the earthquake and ensuing tsunami. From the crippled nuclear power plant, appreciable quantities of radioactive material were emitted to the surrounding environment. Those substances which emitted to air may fall on the ground together with raindrops and runoff to rivers. Elucidation of those processes is the task which our hydrological society should undertake.

• 대한지리학회지
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• 제43권5호
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• pp.743-760
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• 2008

이 논문은 미국 매릴랜드 주의 우선투자지역 설정과 이에 기반한 인센티브 프로그램이 기반시설의 투자위치에 어떤 영향을 주고 있는지를 검증하려는데 그 목적을 두고 있다. 매릴랜드 주의 우선투자지역 프로그램은 도시스프롤을 억제하고 있는가? 이 물음에 대한 답을 구하기 위하여 본 연구에서는 1997년부터 2003년의 기간 동안 주 내의 각 카운티로부터 상하수도 기반시설 투자에 대한 자료를 수집하였다. 실증분석은 두 부분으로 구성되어 있다. 첫 번째 부분은 1997년과 2003년 사이에 카운티별로 우선투자지역의 내부와 외부에 이루어진 상하수도 시설 투자의 패턴을 대상으로 한 분석이다. 두 번째 부분에서는 카운티 단위에서 우선투자지역의 내부 혹은 외부로 투자결정이 이루어지는데 영향을 준 조건들을 확인하는 분석이다. 분석을 위하여 다양한 방식의 회귀모형이 이용되었다. 분석의 결과 주정부의 지원금은 애초의 의도했던 바와 같은 역할을 한 것으로 확인되었다. 모든 추정방식에서 주정부 지원금의 계수값은 유의하였으며 기대한 바와 같은 방향으로 영향을 주고 있었다. 이는 주 정부의 지원금을 많이 받은 카운티일수록 우선투자지역 내부로의 투자가 많았고 외부로의 투자는 작았음을 의미한다.

• 한국지반신소재학회논문집
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• 제18권4호
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• pp.181-191
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• 2019

국내 저수지는 대부분 필댐으로 구성되고 있고, 필댐의 붕괴는 월류와 파이핑이 주된 원인으로 분석되고 있다. 본 연구에서는 원심모형실험기를 이용하여 실제 운영 중인 공주시 ◯◯ 저수지 축조 모형에 대하여 수위승강 시 및 월류 시 저수지의 거동 특성을 고찰하였다. 실제 저수지의 침투 및 월류 모사를 위해서 1/50로 축소한 모형에 파손 및 보강된 복통을 설치하고 제정 보강 및 미보강의 조건을 부여한 후 LVDT, 간극수압계를 설치하고 수위승강시험 및 월류시험을 수행하여 보강방법에 따른 제체의 거동 특성을 검토하였다. 원심모형실험 결과, 수위승강 시험에서 파손된 복통이 제체의 안정에 영향을 미칠 수 있는 것으로 나타났고 반전공법과 보강공법을 병행한 경우 제체의 침투 안정성을 확보할 수 있는 것으로 나타났다. 또한, 월류시험에서 월류유도 수로 설치 시 제체의 세굴과 토사의 유출을 방지할 수 있다는 것을 확인하였다. 본 연구를 통해 저수지 월류유도 수로 및 복통 보강공법 적용에 필요한 기초자료를 제공할 수 있을 것으로 판단된다.

• 한국수자원학회논문집
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• 제55권spc1호
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• pp.1177-1185
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• 2022

상·하수도 시스템은 사람들에게 안전하고 깨끗한 물을 공급해주는 사회기반시설이며, 특히 상·하수도 관로는 지중에 매설되어 있기 때문에 시스템의 결함검출이 매우 어렵다. 이러한 이유로 상·하수도 관로의 진단은 관로 내부에 카메라 및 드론을 통한 촬영을 하여 사후에 촬영된 영상을 바탕으로 시스템 진단하는 등의 사후 결함검출로 제한되기 때문에, 작업자의 업무 효율 증대와 진단의 신속성을 위해서는 관로의 실시간 탐지기술이 필요하다. 최근 첨단장비 및 인공지능 기법을 활용한 시설물 진단 기술이 개발되고 있지만, 인공지능기반 결함검출 기술은 결함 데이터의 종류 및 형태, 수가 검출 성능에 영향을 주기 때문에 다양한 학습데이터가 필요하다. 따라서, 본 연구에서는 상·하수도 관로의 결함검출 시 탐지 성능 향상을 위해 다양한 결함 시나리오를 3D 프린트를 이용하여 구현하고 이를 수집된 결함 데이터와 함께 학습데이터로 사용한다. 이후 수집된 이미지는 위험도에 따른 분류 및 객체의 라벨링 등의 전처리 작업이 수행되고 실시간 결함탐지를 수행한다. 제안된 기법은 상·하수도시스템 결함검출 시 실시간 피드백을 제공함으로써, 작업자의 진단 누락 가능성을 최소화하며 기존의 상·하수도관 진단업무 처리능력을 향상할 수 있다.