• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.1
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• pp.13-34
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• 2000

본 연구에서는 서기 2년부터 1977년까지 남.북한 역사지진(A.D 2-1904)과 초기 계기 지진(1905-1977) 목록을 이용하여 남한 지진 규모로 재조정된 지진목록을 작성하였다 역사 지진은 과거의 협소한 인구분포로 인해 지진 기록의 누락이 많앗다 지진 위험도를 작성하기 위해 지진 발생분포와 지체구조의 특성을 고려하여 4개의 지진구(seismic province)를 설정하였다. 각 지진구에서 최대 잠재 지진결정은 Gumbel의 최대치 이론을 이용하였다 제 1수정 점근 함수 분포에서 유한 상한 값(finte upper boundary) 의 존재는 각 지진구에서 발생할 최대 잠재 지진의 진원(source)이 유한하다는 사실과 잘 일치한다. 따라서 이를 근거로 각 지진구에서 10년 , 20년, 30년, 50년 이내에 2% 5% 10% 초과 확률을 갖는 최대 규모지진을 추정하였다 또한 각 지진구에서 유한 지진원은 과거에 발생했던 큰 규모의 특정 지진과 지진 지체구조 정보에 근거하여 결정하였다. 연구결과 조선시대(1392-1904) 의 지진위험도에서는 경주 울산지역과 서울과 평양지역을 따라 높은지반 가속도 값을 보이며 경주지역에서 0.24g의 최대 지반 가속도 값으로 나타났다 계기 지진목록(1905-1998)을 이용한 한반도의 지진 위험도에서는 경주, 울산, 대구 지역에서 0.10-0.12g 의 최대 지반가속도 값을 보였다. 그리고 계기 지진 목록(1905-1998) 만을 이용하여 작성한 서울.경기 지역의 지진 위험도에서는 김포, 잠실 , 성남 지역의 한강을 따라 분포하는 충적층과 강남지역의 지반 운동이 한강 이북의 대보 화강암 지역에 비해 비교적 높은 0.09-0.10g의 지반 가속도를 보이는 것이 특징이다.

• Journal of the Korean Geotechnical Society
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• v.34 no.9
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• pp.43-49
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• 2018

Seismic hazard assessments are performed on a variety of infrastructure projects. One component of a seismic hazard assessment is the attenuation relationship. Several attenuation relationships have been developed over the decades to predict peak ground acceleration under a variety of site conditions. For example, many attenuation relationships were designed to estimate peak ground acceleration, as well as other intensity measures, under a variety of soil conditions, mostly using the average shear wave velocity for the upper 30 m of earth material as a classification scheme. However, certain types of infrastructure, such as tunnels and nuclear power plants, are typically founded on and in bedrock. Using data from Japan, we developed a simple correlation to estimate peak ground acceleration for rock sites and compare the results from another popular attenuation relationship. Results indicate the popular attenuation relationship to be less than the proposed model for distances less than 200 km.

• The Journal of Engineering Geology
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• v.33 no.2
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• pp.293-305
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• 2023

Three ground models are analyzed using a 1g shaking table and laminar shear box (LSB) to investigate the impact of the ground structure on seismic wave amplification during earthquakes. Multi-layer horizontal, embankment, and basin ground models are selected for this investigation, with each model being divided into dense and loose ground layers, Accelerometers are installed during the construction of each ground model to capture any seismic wave amplification owing th the propagation of an artificial seismic wave, sine wave sweep, and 10-Hz sine wave through a given ground model. The amplification of the tested seismic waves is analyzed using the observed peak ground acceleration and spectrum acceleration. The observed acceleration amplification in the multi-layer horizontal ground model is significantly higher the seismic waves that propagated across the dense ground-loose ground boundary compared with those that only propagated through the dense ground. Furthermore, the observed acceleration amplification gradually increases in the central part of the multi-layer embankment and basin models for the seismic waves that propagated across the dense ground-loose ground boundary.

• Geotechnical Engineering
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• v.1 no.1
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• pp.13-20
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• 1985

In this paper, earthquake response of the Bangkok area in Thailand was analyzed in terms of the acceleration response spectrum and maximum acceleration of the computed surface motions. The program SHAKE was employed to analyse the ground motion. With increasing the maximum acceleration and predominant period of given base rock motion, the computed maximum ground surface acceleration increases. but converges on a maximum value of about 0.39. The characteristics of earthquake response spectrum in the Bangkok area are also discussed and illustrated.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.21-28
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• 1999

The objective of the study is to develop attenuation equations of the ground motions in the southern part of the Korean peninsula. The earthquake source characteristics and the medium properties were estimated from available instrumental earthquake records and used as input parameters. The peak ground accelerations(PGA) and pseudo-velocity response spectra(PSV) were simulated by the random vibration theory. The attenuation equations for the PGA and PSV were constructed in terms of local magnitudes and hypocentral distances.

• Computational Structural Engineering
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• v.4 no.3
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• pp.107-115
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• 1991

A probabilistic-Fuzzy model for seismic hazard analysis is developed. The proposed model is able to reproduce both the randomness and the imprecision in conjunction with earthquake occurrences. Results-of this research are (a) membership functions of both peak ground accelerations associated with a given probability of exceedance and probabilities of exceedance associated with a given peak ground acceleration, and (b) characteristic values of membership functions at each location of interest. The proposed probabilistic-fuzzy model for assessment of seismic hazard is successfully applied to the Wasatch Front Range in Utah in order to obtain the seismic maps for different annual probabilities of exceedance, different peak ground accelerations, and different time periods.

• Journal of the Korean Geotechnical Society
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• v.36 no.11
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• pp.21-33
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• 2020

Ground response analysis has been conducted for each borehole data in Pohang area, using 1D equivalent linear method program, to investigate the applicability of amplification factor to estimate peak ground acceleration. Earthquake motions for ground response analysis were prepared by matching response spectrums for return period of 500, 1000, and 2400 years suggested by seismic design code (MOIS, 2017). Ground survey data were acquired from Geotechnical Information DB System. It has been confirmed that response spectrum obtained from ground response analysis showed good agreement with those from seismic design code irrespective of ground classification. However, PGA (Peak Ground Accelerations) of ground response analysis did not coincide with PGA calculated using amplification factor suggested by seismic design code.

• The Journal of Engineering Geology
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• v.20 no.3
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• pp.339-348
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• 2010

As part of preparing for future earthquakes near three LNG receiving terminals located in coastal regions of Korea, acceleration monitoring systems were installed at four free field sites and on a pile foundation beneath a storage tank in a receiving terminal. Several equipments and accessories were devised to successfully install and operate the monitoring system at LNG receiving terminals. Synthetic earthquake-alarming software systems designed for decisionmaking, based on peak ground acceleration computed using the measured data, were developed for rapid response during earthquakes, not only in each local terminal area but also in the central control division. In addition, a framework software linking nationwide data on peak ground accelerations was included in the integrated earthquake alarming system in the central division, for various future applications. The earthquake alarming systems developed in this research for LNG receiving terminals, based on acceleration monitoring, represent a useful framework for industrial facilities located in coastal regions, where geotechnical conditions may show marked spatial variations.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.1
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• pp.63-76
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• 2000

구조물-지반 상호작용에서 알려진 것처럼 구조물 지진응답은 구조물하부 지반조거에 따라 영향을 받는데 UBC-97을 포함한 여러내진설계규준에서 지반사태 영향을 반영하고 있다 이 연구에서는 기초크기 기초밑 지반깊이, 입력지진 작용점 및 기초 근입깊이 등의 영향을 살펴보고 깊은 지반 위에 세워진 구조물의 평균응답스펙트럼을 UBC-97 탄성응답스펙트럼과 비교하기 위해 구조물-지반 상호작용을 고려한 지진해석을 가상 3차원 유한요소법과 부구조물법을 이용하여 1952년 Taft와 1940년 El Centro 지진기록을 주파수영역에서 수행하였다 연구결과에 의하면 기초크기는 구조물 응답에 별 영향이 없고 기초저면 지반깊이는 구조물체계의 고유주기와 최대가속도를 변경시켰다 또 입력지진의 합리적 작용점은 기초저면이라는 것이 확인되었으며 깊은 지반위에 놓인 기초의 근입은 저주기영역에서 구조물 응답을 상당히 줄어들게 하였다 한편 30m 깊은 지반위에 세워진 구조물의 평균가속도와 UBC-97 가속도를 비교한 결과 UBC-97 탄성응답스펙트럼에 의한 구조물 내진설계가 안전하지 못할 수도 있으므로 UBC-97 지진계수의 할증이 필요하다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.217-223
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• 2019

In this study, the acceleration changes of the surrounding ground when crushed stones were installed in a strip-type were analyzed using the 1-G shaking table test. The ground was constructed from clay, and the foundation was installed using crushed stone of strip-type form. The response acceleration and response spectrum for various input seismic motions were analyzed. The change in acceleration was examined according to the adjacent distance to the strip-type crushed stone foundation. In the Hachinohe seismic motion results, there was no significant decrease in acceleration, but the maximum response acceleration for the two seismic motions was inversely proportional to the distance from the crushed stone foundation. As a result of the response spectrum analysis, the attenuation period in the long period and the short period input wave were different from each other, and the change in response spectrum affected the maximum acceleration value. As the distance from the crushed stone foundation was increased, the attenuation was larger in the period between 0.08 and 0.5 sec in the Hachinohe seismic motion, the attenuation was larger in the period of less than 0.2 seconds in the Northridge seismic motion.