• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.345-352
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• 1998

Free-field ground motion during earthquake is significantly affected by the local site conditions and the behavior of structure is influenced by ground motion, it is essential to perform the reliable site characterization and to determine the site specific earthquake response. In this study, case study of site specific ground response evaluation was performed at Inchon area. Step by step procedures for site characterization and one-dimensional site response analysis were introduced and the importance of site specific analysis was verified.

• Steel and Composite Structures
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• 제26권2호
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• pp.197-211
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• 2018

The study presents the earthquake performance of the Bosphorus Bridge under multi-point earthquake excitation considering the spatially varying site-specific earthquake motions. The elaborate FE model of the bridge is firstly established depending on the new considerations of the used FEM software specifications, such as cable-sag effect, rigid link and gap elements. The modal analysis showed that singular modes of the deck and the tower were relatively effective in the dynamic behavior of the bridge due to higher total mass participation mass ratio of 80%. The parameters and requirements to be considered in simulation process are determined to generate the spatially varying site-specific ground motions. Total number of twelve simulated ground motions are defined for the multi-support earthquake analysis (Mp-sup). In order to easily implement multi-point earthquake excitation to the bridge, the practice-oriented procedure is summarized. The results demonstrated that the Mp-sup led to high increase in sectional forces of the critical components of the bridge, especially tower base section and tensile force of the main and back stay cables. A close relationship between the dynamic response and the behavior of the bridge under the Mp-sup was also obtained. Consequently, the outcomes from this study underscored the importance of the utilization of the multi-point earthquake analysis and the necessity of considering specifically generated earthquake motions for suspension bridges.

• 한국지진공학회논문집
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• 제3권4호
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• pp.1-10
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• 1999

지진 시 지반의 자유장 운동은 국지적 지반조건에 의하여 크게 영향을 받으며 내진설계에 앞서 지반조건을 고려한 부지응답특성평가를 수행하여야 한다. 본 논문은 부지고유의 지반거동 평가를 위하여 필요한 절차를 국내 내진기준과 외국의 기술현황 조사를 바탕으로 제안하였다. 부지응답특성 평가의 개요를 설명하고 1차원 등가선형 해석에 필요한 지반자료 획득을 위한 지반조사계획 기반조사기법, 저변형율 및 고변형율 영역에서의 지반의 변형거동특성, 현장 및 실내시험결과를 이용한 부지특성평가방법들을 제안하였다 또한 제안된 절차를 따라 수행된 인천 지역의 부지특성평가방법들을 제안하였다 또한 제안된 절차를 따라 수행된 인천 지역의 부지응답특성평가 예를 포함하였다.

• 한국지진공학회논문집
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• 제20권4호
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• pp.257-268
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• 2016

In the companion papers (I, II), site-specific response analyses were performed at more than 300 domestic sites and a new site classification system and design response spectra (DRS) were proposed using the results of the site-specific response analyses. In this paper, the proposed site classification system and the design response spectra are compared with those in other seismic codes and verified by different methods. Firstly, the design response spectra are compared with the design response spectra in Eurocode 8, KBC 2016 and MOCT 1997 to estimate quantitative differences and general trends. Secondly, site-specific response analyses are carried out using $V_S$-profiles obtained using field seismic tests and the results are compared with the proposed DRS in order to reduce the uncertainty in using the SPT-N value in site-specific response analyses in the companion paper (I). In addition, site coefficients from real earthquake records measured in Korean peninsula are used to compare with the proposed site coefficients. Finally, dynamic centrifuge tests are also performed to simulate the representative Korean site conditions, such as shallow depth to bedrock and short-period amplification characteristics. The overall results showed that the proposed site classification system and design response spectra reasonably represented the site amplification characteristic of shallow bedrock condition in Korea.

• 한국지반공학회논문집
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• 제34권5호
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• pp.19-35
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• 2018

최근 경주지진과 포항지진과 같이 중규모 이상 지진이 빈번이 발생함에 따라 피해기능성이 커질 수 있는 중서부 도시 지역들에 대한 종합적 지진재해 대책 수립의 필수기본 정보인 지역적 부지고유 지진응답 공간정보 예측의 필요성이 증대되고 있다. 특히 경기도 지역을 대상으로 정량적 부지고유 지반응답 특성 파악의 필요성이 증대됨에 따라 대상 확장영역 내 전략적 지반조사 자료의 확보 및 연계적 부지특성 파악 연구가 다각도로 진행되고 있다. 이에 본 연구에서는 경기도 지진취약지역 도출 및 부지고유 지진응답특성 분석을 위한 위사결정 프레임웍을 제시하였다. 시추조사 자료 및 수치표고모델 등의 지표피복 자료를 수집함으로써 지반지진공학적 연계활용을 위한 GIS 플랫폼 기반의 Geo-Data를 구축하였다. 지구통계학적 공간보간 기법의 최적화 설계를 통해 지층분포 특성 및 연계 취약도 성분 도출을 위한 지반 공간그리드를 구축하였으며, 이를 통해 지진지반응답 매개변수의 공간구역화를 수행하였다. 이에 따라 경기도 지역의 정량적 부지효과를 고려한 경기도 맞춤형 지진방재대책 수립을 위한 기저 정보로서 활용하였다.

• 한국지진공학회논문집
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• 제20권3호
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• pp.171-180
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• 2016

Earthquake event keeps increasing every year, and the recent cases of earthquake hazards invoke the necessity of seismic study in Korea, as geotechnical earthquake hazards, such as strong ground motion, liquefaction and landslides, are a significant threat to structures in industrial hub areas including coastal facilities. In this study, systemized framework of integrated assessment of earthquake-induced geotechnical hazard was established using advanced geospatial database. And a visible simulation of the framework was specifically conducted at two coastal facility areas in Incheon. First, the geospatial-grid information in the 3D domain were constructed with geostatistical interpolation method composed of multiple geospatial coverage mapping and 3D integration of geo-layer construction considering spatial outliers and geotechnical uncertainty. Second, the behavior of site-specific seismic responses were assessed by incorporating the depth to bedrock, mean shear wave velocity of the upper 30 m, and characteristic site period based on the geospatial-grid. Third, the normalized correlations between rock-outcrop accelerations and the maximum accelerations of each grid were determined considering the site-specific seismic response characteristics. Fourth, the potential damage due to liquefaction was estimated by combining the geospatial-grid and accelerations correlation grid based on the simplified liquefaction potential index evaluation method.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.17-24
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• 1999

The porvision against earthquakes and aseismic design of nuclear power plants (NPPs) in Korea are composed of four stages: site-selection, design, construction, and operation stages, Since regulatory criteria are strictly applied in each stage, the NPPs in Korea are believed to have a sufficient safety against maximum potential earthquakes. However, it has been recognized that those regulatory criteria borrowed from U.S. should be replace by Korea-specific ones by using earthquake data obtained from earthquake observation at and around NPP sites. Also, the government made a plan after the Yongwol and th Kyongju earthquakes that the regulatory body operates an independent earthquake network in order to reinforce the earthquake preparedness of NPPs. In compliance with the government's plan, this project is aiming at deployment of an earthquake motoring network composed of four seismic stations at NPP sites to record earthquake ground motions at NPP sites, to derive attenuation formulas of various ground motions and site-specific response spectra, and to develop structural intergrity assesment program.

• 한국지진공학회논문집
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• 제4권2호
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• pp.37-46
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• 2000

본 논문에서는 부지특성을 고려한 설계지반운동의 산정방법을 연구하였으며 그 해석결과를 지반 구조물의 내진설계에 적용하는 방법을 제안하였다 지진응답 해석시 사용되는 설계응답스펙트럼과 설계시간 이력등의 입력운동의 통제점 위치가 지반구조물 내진설동 지층내 암반운동 그리고 노두운동을 사용하는 방법으로 나눌 수 있고 이에 따라 작용 설계지진운동이 변화하므로 지반구조물의 경계조건에 적합한 방법을 사용하여야 한다.

• Earthquakes and Structures
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• 제9권2호
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• pp.391-413
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• 2015

Damage of torsionally coupled buildings situated on soil sites has been reported in literature, however no site-specific studies are available for torsionally coupled buildings having site characteristics as a parameter. Effect of torsion is being accounted in seismic codes by the provision of design eccentricity where the dynamic to static eccentricity ratio is a parameter. In this paper, a methodology to determine dynamic to static eccentricity ratio of torsionally coupled buildings has been demonstrated for Delhi region for two torsionally coupled buildings on three soil sites. The variations of average and standard deviations of frame shears for stiff and flexible edges are studied for four eccentricity ratios for the two buildings for the three sites. From the limited studies made, it is observed that the dynamic to static eccentricity ratios observed for site-specific earthquakes are different from Indian seismic code specified value, hence a proposal is made to include a comment in Indian seismic code. Methodology proposed in this paper can be adopted for any region, for the estimation of dynamic to static eccentricity ratio for site specific earthquake.

• Earthquakes and Structures
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• 제27권4호
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• pp.303-315
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• 2024

This study proposes a comprehensive methodology for estimating accumulative damage of bridge structures under multiple seismic excitations, in the framework of site-specific probabilistic hazard analysis. Specifically, a typical earthquake-prone region in China is chosen to perform probabilistic seismic hazard analysis (PSHA) to find the mean annual rate (MAR) of ground motion intensity at a specific level, based on which, a mass of ground motion observations is selected to construct random earthquake sequences with various number of shocks. Then, nonlinear time history analysis is implemented on the finite element (FE) model of a RC girder bridge at the site of interest, to investigate structural responses under different earthquake sequences, and to develop predictive model for cumulative damage computation, in which, a scalar seismic intensity measure (IM) is adopted and its performance in damage prediction is discussed by an experimental column. Furthermore, a mathematic model is established to calculate occurrence probability of earthquakes with various number of shocks, based on PSHA and homogenous Poisson random process, and a modified cumulative damage indicator is proposed, accounting for probabilistic occurrence of various earthquake scenarios. At end, the applicability of the proposed methodology to main shock and aftershock scenarios is validated, and characteristics of damage accumulation under different multiple earthquake scenarios are discussed.