• Journal of the Earthquake Engineering Society of Korea
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• v.1 no.1
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• pp.57-67
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• 1997

The objective of present paper is to investigate elasto-plastic behaviour and estimate the resistance capacity of a beam-shear wall structural system against earthquake ground accleration exciations. Pushover analysis is adopted to estimate inttiate and post stiffnesses and yielding point for inelastic response analysis in LPM (Lumped Parameter Mass) model, and modified Clough model is used as the hysteresis rule of each story. Three earthquake waves are used in the analysis but their peak ground accelerations are changed to be 0.12g, 0.24g. It is assumed that the earthquakes act in the longigtudianl direction of a 25 Story apartment building which consists of two some unit plan. The distribution of story ratio and ductility ratio are estimated and discussed within Korean, Japanese code and UBC.

• Journal of the Earthquake Engineering Society of Korea
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• v.1 no.1
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• pp.51-56
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• 1997

The objective of this study is to review the current state of earthquake simulation tecniques using the shaking table and check the reliability. One degree-of-freedom(d.o.f) and three d.o.f aluminium shear models were used and $4m{\times}4m$ 6 d.o.f shaking table was excitated in one horizontal direction to simulate 1940 El centro earthquake accelerogram (NS component). When the actual acceleration history of shaking table is compared to the desired one, it can be found that the overall histories are very similar, but that the lower frequency range (0~2 Hz) of the actual excitation has generally lower amplitude than that of the desired in Fourier transform amplitude. Free vibration and white noise tests have shown almost the some values for natural frequencies, but shown quite different values for damping rations, that is, 1.37% in case of free vibration test vs 14.76 % in case of white noise test. The time histories of story shear driff show the globally linear elastic behaviors. But the elliptical shape of the histories with one of the axis being the stiffness of the story implies the effect of viscous damping.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.3 s.43
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• pp.59-68
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• 2005

The energy-based seismic design method Is more rational in comparison with current seismic design code in that it can directly account for the effects of cumulative damage by earthquake and hysteretic behavior of the structure. However there are research results that don't reach a consensus depending on the ground motion characteristic and structural properties. For that reason in this study the influences of ground motion characteristics and structural properties on energy demands were evaluated using 100 earthquake ground motions recorded in different soil conditions, and the results obtained were compared with those of previous works. Results show that ductility ratios and sue conditions have significant influence on input energy. The results show that the ratio of hysteretic to input energy is considerably influenced by the ductility ratio, damping ratio, and strong motion duration, while the effect of site condition is insignificant.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.2
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• pp.175-182
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• 2006

The efficient management for minimum losses and demage precautions of fragile region against coastal disasters such as seismic waves and seawater overflows is proceeding continually. This study is to analyze inundation trace and extract expected damage areas with historic records of tsunami using Geographic Information System. Creating a digital elevation model of the Mangsang and the Nobong region in the east coast, we marked inundation record of tsunami and forecasted the flood area with a seismic wave height between 3 m and 5 m. The inundation trace layers and the expected damage areas on the cadastral map layer were superimposed individually. Consequently, the range and lot numbers of inundation expected area were calculated and inundation areas of 5 m tsunami were increased by 2.8 times than 3 m tsunami in case of subject regions. Analyzed results are expected to use evacuation work in case of seismic waves and to predict the compensation of the damaged area. And this study is expected to use suitable countermeasure for prevention from natural disasters.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2818-2827
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• 2015

The spatial patterns and characteristics of these sequential earthquakes and ground motions induced by the earthquakes are examined by contours of peak ground velocity (PGV) and geometric mean peak ground velocity (GMPGV) using both ordinary kriging in geographical information system (GIS) and data, the records obtained from strong motion stations, acquired after recent sequential earthquakes in Canterbury, New Zealand (NZ). The performance of underground water pipeline system is examined by using data acquired after earthquakes. The spatial distribution of GMPGV is superimposed on water pipeline repairs throughout the water distribution system in areas affected principally by transient ground motion using GIS and then water pipeline repair rates, expressed as repairs/km, for different types of pipe are evaluated relative to the estimated GMPGV outside liquefaction areas. The earthquake performance of underground water pipeline systems is summarized in this study.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.5
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• pp.223-232
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• 2021

The spatial variation characteristics of seismic motions at the nuclear power plant's site and structures were analyzed using earthquake records obtained at the Fukushima nuclear power plant during the Great East Japan Earthquake. The ground responses amplified as they approached the soil surface from the lower rock surface, and the amplification occurred intensively at about 50 m near the ground. Due to the soil layer's nonlinear characteristics caused by the strong seismic motion, the ground's natural frequency derived from the response spectrum ratio appeared to be smaller than that calculated from the shear wave velocity profile. The spatial variation of the peak ground acceleration at the ground surface of the power plant site showed a significant difference of about 0.6 g at the maximum. As a result of comparing the response spectrums at the basement of the structure with the design response spectrum, there was a large variability by each power plant unit. The difference was more significant in the Fukushima Daiichi site record, which showed larger peak ground acceleration at the surface. The earthquake motions input to the basement of the structure amplified according to the structure's height. The natural frequency obtained from the recorded results was lower than that indicated in the previous research. Also, the floor response spectrum change according to the location at the same height was investigated. The vertical response on the foundation surface showed a significant difference in spectral acceleration depending on the location. The amplified response in the structure showed a different variability depending on the type of structure and the target frequency.

• The Korean Journal of Archival Studies
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• no.21
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• pp.85-116
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• 2009

Records are the social memory storage including collective memory about region, it is impossible to put into and represent all aspects of society with only public records. Japan showed the possibilities of cooperative collecting and the positive records producing and collecting efforts between organizations, even if it was not accomplished by systemic documentation strategy. Some characteristics were found out when this case was reviewed, it is as follows. To begin with, it is the cooperation and share in collecting. Especially, the activities of private organizations look better than public organizations and the cooperative collecting efforts lead to transmit much more social memory and historical records to next generation. Secondly, it is the positive records producing and collecting. The private organizations also left many records of various activities of those one accord. They recognized that recording experience and leaving behind is the survivors' responsibility. We cannot help recognizing the growth of a sense of duty and historical consciousness to record their own experience with undergoing big disaster, earthquake. Thirdly, there was no limit when it comes to the collecting scope. All records related with people and place in disaster area were the target for collecting just like slogan, 'Let's transmit records to next generation as much as possible', 'Common records and resources deserve leaving, because it is important life's information proving situations of the time. We were able to confirm the high will and enthusiasm about 'how, what and why do we transmit something of society to next generation' in this case.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.11a
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• pp.69-70
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• 2011

최근 해저지진의 활동에 따른 극한 쯔나미 파랑이 해안도시와 항만에 어마어마한 손상을 가져오고 있다. 전세계에 걸쳐 특정해역에서는 강한 정진형태의 부진동과 처오름이 관측되고 있다. 한반도에서는 그렇게 빈번한 발생을 나타내고 있지는 않으나, 과거기록을 보면 동해에서 몇 개의 중요한 발생사례도 존재한다. 본 연구에서는 특히 만이나 내수해역에서 최근 해저지진의 발생 추이를 분석하고 이에 따른 쯔나미 발생 메카니즘을 해석하여 새롭게 내수역에서의 수치모델에의 적용을 통해 공진을 통한 쯔나미 파랑의 변환을 다루어 통항선박에 대한 안정성 확보에 기초자료를 제공하고자 하였다. 내수역에서의 쯔나미 파랑에 대한 반응을 정합성 및 웨이블릿 해석으로 탁월 주기와 지속시간에 대한 분석으로 파악하였으며, 쯔나미파의 입사와 독립적인 공진모드의 도출은 쯔나미 재해의 경감을 위한 시설물 및 재난지역을 식별하는데 도움을 주고, 나아가서는 장래 재난에 대한 적절한 대비에 기여할 수 있을 것으로 본다.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.6
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• pp.413-424
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• 2016

The vertical design spectrum for Korea, which is known to belong to an intra-plate region, is developed from the ground motion records of the earthquakes occurred in Korea and overseas intra-plate regions. From the statistical analysis of the vertical response spectra, a mean plus one standard deviation spectrum in lognormal distribution is obtained. Regression analysis is performed on this curve to determine the shape of spectrum including transition periods. The developed design spectrum is valid for the estimation both spectral acceleration and displacement. The ratio of vertical to horizontal response spectrum for each record is calculated. Statistical analysis of the ratios rendered the vertical to horizontal ratio (V/H ratio). Subsequently the ratio between the peak vertical ground acceleration to the horizontal one is obtained.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.1
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• pp.33-42
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• 2021

The design response spectrum presented in the seismic design standard reflects the characteristics of the tectonic environment at a site. However, since the design response spectrum does not represent the ground motion with a specific earthquake magnitude or distance, input ground motions for response history analysis need to be selected reasonably. It is appropriate to use observed ground motions recorded in Korea for the seismic design. However, recently recorded ground motions in the Gyeongju (2016) or Pohang (2017) earthquakes are not compatible with the design response spectrum. Therefore, it is necessary to convert the recorded ground motion in Korea to a model similar to the design response spectrum. In this study, several approaches to adjust the spectral acceleration level at each period range were tested. These are the intrinsic and scattering attenuation considering the earthquake environment, magnitude, distance change by the green function method, and a rupture propagation direction's directivity effect. Using these variables, the amplification ratio for the representative natural period was regressed. Finally, the optimum condition compatible with the design response spectrum was suggested, and the validation was performed by converting the recorded ground motion.