• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.2
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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.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.1
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• pp.39-58
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• 2004

It is very important that predict the inelastic seismic behavior exactly for seismic performance evaluation of a building in the performance based seismic design. Evaluation method of seismic performance based on the pushover analysis reflected in PBSE was developed by some researchers. For the evaluation of inelastic global and local seismic responses by pushover analysis exactly. lateral load distribution should be adjusted and reflected the dynamic characteristics of structural system and various seismic ground motions. And performance point should be determined based on the evaluation of reasonable deformation capacity of a building more exactly. An effective method based on the improved the adaptive lateral load distribution and the equivalent responses of a multistory building is proposed in this study to efficiently estimate the accurate inelastic seismic responses. The proposed method can be used to evaluate the seismic performance for the global inelastic behavior of a building and to accurately estimate its local inelastic seismic responses. In order to demonstrate the accuracy and validity of this method, inelastic seismic responses estimated by the proposed method are compared with those obtained from other analytical methods.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.3
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• pp.83-98
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• 2000

유연한 액체 저장탱크 내 유체의 부가질량 및 슬러싱 강성행렬을 도출하는 새로운 방법을 제시하였다. 비점성, 비압축성 이상유체를 표면 출렁임을 고려하여 경계요소법에 의하여 모델링하였다. 유체의 표면과 저장탱크 벽체의 접촉면과 같은 불연속 경계를 다루기 위해 특별한 과정을 도입하였다. 원통형 액체저장탱크의 지진응답해석에 적용하여 우수한 결과를 얻을 수 있음을 확인하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.1
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• pp.1-6
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• 2001

P파와 SV파와 입사할 때 비균질 퇴적층에서의 지진응답을 유한요소법과 경계여소법을 조합하여 해석하였다. 유한요소법을 사용하여 불규칙한 기하형상과 비균질 재료 특성을 모델링하였고, 경계요소법을 사용하여 인위적인 경계로부터 불필요한 파의 반사를 없앨수 있게 반무한 영역을 모델링하였다. 경계요소의 기본해는 반무한 영역문제에서 반드시 고려해야하는 방사조건을 자동적으로 만족시킨다. 따라서 외부영역과 내부영역의 접촉면에서 표면력의 평행조건과 변위의 연속조건을 사용하여 P파와 SV파에 의한 지진응답을 해석하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.5
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• pp.309-317
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• 2021

In this paper, we present the evaluation results for the conservatism of the response acceleration method (RAM), for seismic response analysis of box-type power cable tunnels. We studied 50 examples, considering the cross sections of 25 power cable tunnels, and two soil conditions for each power cable tunnel. A refined dynamic analysis method considering the soil-structure interaction was further employed to evaluate the conservatism of the RAM. The comparison revelated that the seismic responses computed using the RAM were consistent with those obtained using the refined method, since the averages of response ratio (defined as the ratio of the response by RAM to that of the refined method) approached 1.0, and the standard deviations of the response ratio were less than 5%. Finally, we found that applying a load factor of 1.1 to the response of the RAM allowed for a conservative design for seismic loads.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.4
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• pp.23-30
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• 2003

The result of recent seismic hazard analysis indicates that the ground motion response spectra for Korean nuclear power plant site have relatively large frequency acceleration contents. In the ordinary seismic fragility analysis of nuclear power plant structures and equipments, the safety margin of design ground response spectrum is directly used as a response spectrum shape factor. The effects of input response spectrum shape on the floor response spectrum were investigated by performing the direct generation of floor response spectrum from the ground response spectrum. The safety margin included in the design ground response spectrum should be considered as a floor response spectrum shape factor for the seismic fragility analysis of the equipments located in a building.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.2
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• pp.1-12
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• 2000

단층에 근접한 지진동에 대하여 성능이 저하되는 단자유도계의 변위응답에 대하여 연구하였다 5% 의 감쇠비를 갖는 세단계의 성능저하시스템을 5개의 단층에 근접한 지진동에 대하여 해석하였다 해석결과로부터 성능저하시스템의 비탄성 변위응답은 비저하시스템에 비하여 큰 값을 나타냄을 알 수 있었다 또한 성능저하 특성이 증가할수록 변위응답은 커지는 경향이 있다 이러한 변위증폭은 구조물의 고유주기 강도와 성능저하특성에 영향을 받으며 짧은 주기영역에서는 큰 값을 나타내며 긴 주기영역에서는 변위증폭이 거의 발생하지 않는다 단층에 근접한 각각의 지진동에 대한 변위증폭의 최대값은 1초 보다 작은 주기영역에서 비저하시스템의 4배 정도이다 변위증폭계수의 평균값은 짧은 주기영역에서는 2의 값을 가지면 구조물의 고유주기가 길어질수록 1에 수렴해 감을 알 수 있었다.

• Computational Structural Engineering
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• v.4 no.4
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• pp.24-28
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• 1991

본 연구용역에서는 반도기계주식회사의 의뢰에 의거하여 Manbridge Crane의 지진하중에 대한 구조물의 안전성을 평가하였다. 구조해석은 유한요소 모형을 사용하여 사하중, 활하중 및 OBE(Operating Basis Earthquake)와 SSE(Safe Shut-down Earthquake)의 지진하중에 관한 해석을 수행하였다. Crane설치지점의 층응답스펙트럼을 입력으로 한 응답스펙트럼해법으로 지진해석을 수행하였다. Trolley의 위치와 정격하중의 유무에 따라서 5개의 구조모형을 작성하여 해석을 수행하였으며, 지진해석에는 35개의 자유진동모드가 고려되었다. 구조해석을 통하여 1) 구조부재의 과도응력 발생여부, 2) 보강재의 좌굴 가능성, 3) Hoist Rope의 안전성, 4) Crane의 전도의 가능성 및 Seismic Lug의 안전성, 5) 지진하중에 대한 제동력, 6) Crane의 주행 Rail로부터의 탈선여부, 7) Traversing Rail의 수직처짐, 8) 주행 Rail 및 End Stopper의 Anchor Bolt의 안정성, 9) Fuel Basket과 Handrail의 안전성을 검토하였다. 해석결과를 바탕으로 설계시방서에서 제시한 모든 설계요구조건을 만족시킬 수 있도록 수직 Frame의 보강부재를 보강하고, Hoist Rope 용량을 증가시키도록 제안하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.4
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• pp.21-32
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• 2004

A Seismic analysis procedure of bi-directional brideg motions is developed by using mechanical bridge model. A three-dimensional mechanical model can consider major phenomena under bi-directional seismic excitations, such as nonlinear pier motion under biaxial bending, pounding and bearing damage due to the rotaion of the superstructure, etc. The analyses utilizing the uni-directional and the bi-directional bridge model for the 3-span simply supported bridge are then performed. The seismic responses in two cases are examined and compared by investigating the relative displacements of each superstructure to both ground and adjacent superstructures and the restoring forces of RC pier. The analysis using either the uni-directional model or bi-directional model is acceptable for estimating the displacement responses of a bridge, but the bi-directional analysis is found to give more conservative results for resisting forces of RC piers. To make general conclusions, therefore, the analysis using the bi-directional bridge model should be performed in evaluating the seismic safety of bridges.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.955-963
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• 2006

As the geometrical characteristic of the curved bridge, the seismic response of curved bridges are different from straight bridges. This study analyzed the seismic response of the curved bridges considering diverse factors such as radius of curvature, direction of seismic load and support condition. The improved simple modeling of the curved bridge for seismic analysis is proposed, and it is compared with the detail modeling in order to verify the simple modeling. Three simply supported curved bridges and six 3-span continuous bridges are selected for seismic analysis. The behavior of curved bridges are evaluated in terms of the displacement and the force at supports and piers under seismic load applied in various directions. The results of this study show that upward reaction force may appear in simply supported curved bridge under seismic load. And continuous curved bridges are affected by the direction of the seismic load.