• 지구물리
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• 제9권3호
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• pp.249-262
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• 2006

The 29 May 2004 offshore Uljin, Korea earthquake was predominantly thrust-faulting at a depth of approximately 12 (±2) km. The mainshock attained the seismic moment of M0 =5.41 (±1.87)  1016 N m (Mw = 5.1). The focal mechanism indicates a subhorizontal P-axis trending 264° and plunging 2°. The orientation of P- and T-axis is consistent with the direction of absolute plate motion generally observed within the plates, hence the cause of the May 29 shock is the broad-scale stress pattern from the forces acting on the downgoing slab along the Japan trench and inhibiting forces balancing it. The 29 May 2004 earthquake occurred along a deep seated (~12 km), pre-existing feature that is expressed on the surface as the basement escarpment along the western and southern slopes of the Ulleung basin. The concentrated seismicity along this basement escarpment suggests that this feature may qualify as a seismic zone - the Ulleung basement escarpment seismic zone (UBESZ).

• 국제초고층학회논문집
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• 제9권4호
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• pp.315-323
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• 2020

In June 2016, the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) in Japan delivered countermeasures against long-period ground motions caused by strong earthquakes along the Nankai trough. However, the countermeasures do not cover high-rise buildings equal to or shorter than 60 m in height, which do not require earthquake response analyses in the seismic design. Hence, in the present study, earthquake response analyses for such high-rise reinforced concrete (RC) buildings were performed under artificial ground motions assumed in the OS1 and OS2 regions to determine the base shear coefficients that satisfy a given safety demand. Furthermore, the results from the earthquake response analyses were estimated by the authors' proposed method based on the equivalent linearization method, showing good agreement and inspiring suggestions for more accurate and simplified estimations.

• 자원환경지질
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• 제55권4호
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• pp.421-428
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• 2022

본 연구는 2022년 발표한 한국의 제6회 과학기술예측조사와 2019년 발표한 최신의 일본 과학기술예측조사 결과에 주목하여 최근 지질자원 분야에서 국가·사회적으로 높은 기대를 받고 있는 지진재해와 우주이용에 관한 미래기술을 분석하였다. 한국의 2022년 발표한 지진재해 관련 미래기술은 2017년 제시한 지진 예측 및 조기경보 기술 형태와 달리 지진·복합재난 정보기술과 공공데이터 플랫폼으로 제시되었고, 건물·도시의 재난대응 생활밀착 로봇에 적용하는 형태로 제시되었다. 일본 2019년 과학기술예측조사에서는 한국의 3배 수준의 많은 미래기술이 제시되었으며, 지진재해 기술 또한 대규모 지진 예측, 지층 주입에 따른 유발 지진 예측, 전국 액상화 위험 규명, 규모 광역 응력 측정, 사물인터넷(IoT) 혹은 인공지능 관측 영상 분석에 의한 지진 재해 감시·예측 등 상세 기술이 제시되었다. 최신 한국과 일본의 과학기술예측조사의 우주이용 기술은 물/얼음, 헬륨-3, 희토류 금속 등의 자원을 채굴하는 로봇 기술과 달·화성에서 현지자원을 활용한 유인기지 기술 형태로 더욱 구체화되었다. 일본의 기술적 실현시기를 비교해 보면 2019년에 예측한 실현시기가 2015년의 조사결과보다 4~10년 정도 지연되었다. 2019년 이후에도 코로나19 전염병 상황, 2020년 한국과 일본의 탄소중립 선언, 2022년 러시아-우크라이나 전쟁 등 환경변화에 따라 한국과 일본의 미래기술 실현시기의 예측 결과의 불확실성이 더 커질 수 있다. 하지만 앞으로 지질자원 분야에서 정보기술과 연계한 지진재해 및 우주이용 기술에 대한 더욱더 활발한 연구개발이 요구된다.

• 기술사
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• 제41권4호
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• pp.47-51
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• 2008

The different result and response of the earthquakes, occurred consecutively at China and Japan in May and June. respectively, is suggestive of the importance of preparedness against earthquake disaster. We learned lesson, although indirect, that the earthquake early warning. earthquake-resistant design, and people's concepts on earthquake can greatly reduce the earthquake hazards. The more preparedness we have in present, the less hazards we will experience for future.

• Earthquakes and Structures
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• 제8권4호
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• pp.889-913
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• 2015

Structural vibration characteristics of a semi-active base-isolated building were investigated using seismic observation records including those of the 2011 Great East Japan earthquake (Tohoku earthquake). Three different types of analyses were conducted. First, we investigated the long-term changes in the natural frequencies and damping factors by using an ARX model and confirmed that the natural frequency of the superstructure decreased slightly after the main shock of the Tohoku earthquake. Second, we investigated short-term changes in the natural frequencies and damping factors during the main shock by using the N4SID method and observed different transition characteristics between the first and second modes. In the second mode, in which the superstructure response is most significant, the natural frequency changed depending on the response amplitude. In addition, at the beginning of the ground motion, the identified first natural frequency was high possibly as a result of sliding friction. Third, we compared the natural frequencies and damping factors between the conditions of a properly functional semi-active control system and a nonfunctional system, by using the records of the aftershocks of the Tohoku earthquake. However, we could not detect major differences because the response was probably influenced by sliding friction, which had a more significant effect on damping characteristics than did the semi-active dampers.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.15-19
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• 2009

Due to the Japan's Kobe earthquake in 1995, a cut-and-cover tunnel, which is one of subway facilities, collapsed unexpectedly. As a result, also in Korea, seismic performance needs to be secured for the cut-and-cover tunnel and currently, the subway seismic design standard is based on the seismic performance. However, there is no standard for the damage level or stability level of a member for securing the seismic performance, and the definition of multi-level seismic performance is not sufficient. By contrast to this situation, in the Japan's evaluation method of seismic performance, design earthquake ground motion having reflected there into the subway driving stability is clearly defined and the seismic performance required for structures is classified in detail. This study analyzes the Japan's systematic evaluation method of seismic performance for cut-and-cover tunnels of subway.

• 한국전산구조공학회논문집
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• 제13권1호
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• pp.63-74
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• 2000

본 연구는 해외각국의 RC건물의 내진화기술 가운데, 일본의 기존 RC건물에 대한 내진성능의 평가수법인 내진진단규준의 현황을 소개함과 동시에 그 적용사례 및 지진대책에의 활용가능성을 분석·검토하여, 향후 한국실정에 맞는 RC건물의 내진화기술의 개발에 기초적인 자료로서 활용하고자 하는 것이 주목적이다. 이를 위해 본 연구에서는 일본의 동경도에서 최근 실시되어진 지진경험이 없는 RC건물의 내진성능을 내진진단규준에 의한 진단결과인 구조내 진지표(Is)치를 중심으로 통계학적으로 분석하여, 이미 조사되어진 타 지역의 내진성능과 비교·검토하였고, 또한 확률론에 입각하여 대상지역의 Is치의 분포특성과 이미 지진 피해를 받은 지역 건물의 Is치 분포특성을 비교·검토하여 지진피해율을 추정하였다. 본 연구의 결과는 지진에 대한 보강건물의 효율적인 선정 등, 지진대책에 기본적인 자료로서 활용이 가능하며, 또한 일본의 내진성능 평가방법, 통계학적인 분석방법, 확률론에 입각한 지진피해율 평가방법 등의 방법론은 향후 한국의 RC건물에 대한 내진화기술의 개발에 활용이 가능하다고 사료된다.

• 한국전자통신학회논문지
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• 제1권2호
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• pp.95-101
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• 2006

근래에 이르러 인도네시아의 지진해일 때 수많은 사상자가 나오고, 일본근해의 지진의 영향으로 우리나라에도 영향을 미쳤다. 이에 따라, 지진에 대한 대비와 지진이 발생하였을 때의 신속한 정보전달이 중요한 요인이 되었다. 따라서 지진을 감지한 관측지에서 지진의 영향이 우려되는 지역으로의 신속한 정보 전달체계를 확립하고, 더 나은 지진 관측 장비를 개발함으로써, 지진피해로 인한 시민의 재산과 생명의 손실을 최소화 하는데 이바지 하고자 한다.

• 한국지진공학회논문집
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• 제22권3호
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• pp.185-191
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• 2018

Post-earthquake risk assessment technique in Korea is developed in 2013 by National Disaster Management Research Institute, at the same time, related manual and standard regulation is distributed to every local government by National Emergency Management Agency. The objectives of this research are to investigate and evaluate the post-earthquake risk assessment of 9.12 Earthquake (M5.8, Gyeongju City, 2016) and 11.15 Earthquake (M5.4, Pohang City, 2017). To suggest and improve the assessment process of post-earthquake risk, first post-earthquake risk assessment method of advanced foreign countries including US, New Zealand and Japan are compared, and post-earthquake evaluation activities in 9.12 Earthquake and 11.15 Earthquake are analyzed. From the results, it is needed to expand the adapted building and structure types and strengthen the earthquake disaster response capacity of local government.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1389-1396
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• 2008

The recent Sichuan earthquake(2008) in China and Iwate-Miyazaki earthquake(2008) in Japan give Korea peninsula warning that it is no more safety zone against damage by earthquake events. So, rapid and appropriate countermeasures for dam operation and management against earthquake are needed. In Korea earthquake design standard(MOCT, 1997) has been revised after Kobe earthquake. Installation of seismometer and monitoring of earthquake for special class dams is requlated in dam aseismic design standard(MOCT, 2001). Accelerometer installation project for existing dams has been carrying out by K-water to establish an earthquake network for dam safety. Real-time dam earthquake monitoring network has also been developed to detect an earthquake efficiently and to warn to dam administrators as soon as possible. In this study, dam real-time earthquake monitoring system developed by K-water was introduced and applicability of real earthquake record measured by this system to dam safety management was illustrated.