• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.3 s.49
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• pp.57-64
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• 2006

Seismic design codes are mainly based on the research results for the inelastic response of structures in high seismicity regions. Since wind loads and gravity loads may govern the design in low seismicity regions in many cases, structures subjected to design seismic loads will have larger overstrength compared to those of high seismicity regions. Therefore, it is necessary to verify if the response modification factor based on high seismicity would be adequate for the design of structures in low seismicity regions. In this study, the adequacy of the response modification factor was verified based on the ductility and overstrength of building structures estimated from the result of nonlinear static analysis. Framed structures are designed for the seismic zones 1, 2A, 4 in UBC-97 representing the low, moderated and high seismicity regions and the overstrength factors and ductility demands of the example structures are investigated. When the same response modification factor was used in the design, inelastic response of structures in low seismicity regions turned out to be much smaller than that in high seismicity regions because of the larger overstrength of structures in low seismicity regions. Demands of plastic rotation in connections and ductility in members were much lower in the low seismicity regions compared to those of the high seismicity regions when the structures are designed with the same response modification factor.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.2
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• pp.59-66
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• 2001

구조물 내진설계의 개념은 기존요구조건이라는 조항으로 시방서에 규정되어 있으며 구조물이 지진발생시에 안전성과 경제성을 최대한 확보할 수 있으며 비선형시간 이력해석을 수행하여 자진시의 동적거동을 기술함으로써 확인할 수 있다. 내진설계에 보편적으로 적용하는 응답스펙트럼해석법은 선형해석법으로 구조물의 비선형동적거동의 영향을 거동계수로 반영하므로 파괴메카니즘 및 기본 요구조건의 만족여부를 거동계수를 구하는 과정으로 결정할 수 있다. 이 연구에서는 내진설계방식에 의해 설계된 약진지역에 의한 화학공장건물의 모델인 3차원 철골뼈대구조물을 선정하고 거동계수를 결정하는 과정을 수행하여 지진시의 동적거동을 확인하였다. 이 연구의 결과, 현 시방서의 응답스펙트럼해석법에 적용되는 거동계수는 강진지역의 구조물의 경우 기능성 및 안정성 한계를 제시하지만 약진지역 구조물의 경우는 실제 동적거동과 무관하다는것과 약진 지역에 위치한 구조물의 내진설계에는 시방서가 제시한 내진설계방식을 적용하는 것이 주요한 사항임을 확인하였다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.06a
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• pp.223-228
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• 2000

지진격리교량은 강진지역의 지반운동과 구조물의 거동에 근거한 내진설계 개념을 바탕으로 설계되었다. 그러나 지반운동의 특성과 구조물의 거동에 있어서 한반도와 같은 중약진 지역과 지각변동운동이 활발한 강진지역은 큰 차이를 보이고 있다. 따라서 중약진 지역의 내진설계에서는 지반운동의 특성이 반영되어야 할 필요가 있으며, 특히, 지진격리교량의 경우에는 교각의 연성 등 중약진 지역의 구조물의 거동특성이 반영되어야 한다. (중략)

• Journal of Korean Association for Spatial Structures
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• v.11 no.4
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• pp.109-119
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• 2011

To date, a smart base isolation system has been developed in high seismicity region such as Japan, USA etc. Smart base isolation systems developed for structures in high seismicity region cannot directly applied to structures in regions of low-to-moderate seismicity such as Korea. Therefore, problems that occur by applying the smart base isolation system developed for the structures in high seismicity region to the structures in regions of low-to-moderate seismicity have been investigated in this study. To this end, a spacial arch structure was used as an example structure and MR dampers and low damping elastomeric bearings were used to compose a smart base isolation system. Artificial earthquakes were used for ground motions in regions of high and low-to-moderate seismicity. Based on numerical simulation results, it has been known that the capacity of smart base isolation system for the regions of low-to-moderate seismicity should be carefully designed because the base isolation effects of the smart base isolation system for high seismicity region is deteriorated when it is applied to the structures in regions of low-to-moderate seismicity.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.370.2-370
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• 1999

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.03a
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• pp.249-258
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• 2003

강진을 고려한 지진설계 규준은 약진지역에서는 불필요한 경제적 손실을 가져올 수 있고, 지반-구조물 상호작용을 고려한 성능기준 설계가 합리적인 지진설계를 위해서 중요하다는 것이 인식되었다. 이 연구에서는 연약지반 위에 놓인 단자유도계의 탄성, 비탄성 지진응답 해석을 지반의 비선형성을 고려하여 최대지진가속도를 0.07g와 0.11g로 조정한 11개 중, 약진에 대해 수행하였다. 지진 응답해석은 지반-구조물체계에 대해 유사 3차원 동적해석 프로그램으로 암반에 지진기록을 입력하여 한 단계에 일괄적으로 수행하였다. 연구 결과에 의하면 고정지반이나 선형지반을 가정한 지진응답 스펙트럼은 구조물-지반체계의 실제적인 거동을 보여주지 못하는 것으로 나타났으며, 합리적인 지진설계를 위해서는 지진규준에 정해진 일상적인 설계절차에 따라서 수행하는 것보다 다른 성질을 가진 여러 지반에 대해서 성능기준 지진설계를 수행하는 것이 필요하다. 약진을 받는 연약지반의 비선형성도 입력지진동을 증폭시켜 탄성, 비탄성 지진응답 스펙트럼에 심하게 영향을 미쳤으며, 그 현상은 특히 탄성 응답스펙트럼에서 두드러졌다.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.6 s.52
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• pp.67-77
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• 2006

Seismic activity of Korea is not so high as that of Japan or California and most of the structures were designed without considering the influence of earthquakes until the first seismic design code was enforced in 1988. Therefore, it was very hard to find seismically isolated structures in Korea until 1980's. Korean engineers assumed that the seismic isolation or vibration control would be useful only in a high seismicity region while such technologies can be quite useful in a low seismicity region for the efficient reduction of earthquake damages. Recently, Korean engineers began to have interest in the seismic isolation or vibration control and applied it to some important structures such as LNG storage tanks, many bridges and several buildings. However, design codes are not defining such useful advanced technologies for the design of building structures and several projects employing seismic isolation or vibration control in the design of structures had difficulties in obtaining construction permit from the local government. Therefore, it is an urgent requirement to introduce these advanced technologies in the seismic design code.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.4
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• pp.105-110
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• 2000

중약진 지역으로 분류되고 있는 대만에서 1999년에 발생된 예상치 못한 막대한 경제적 피해와 사상자를 기록하였다. 대만과 마찬가가지로 중약진지역으로 분류되는 우리나라에서도 지진발생시 많은 문제발생이 예상됨에 따라 기존건물의 내진성능평가의 필요성의 인식하게 되었다. 본 연구에서는 미국과 일본에서 이미 적용되고 있는 기존 건축물의 내진성능 평가 기법을 분석하고 이를 3층 규모의 모멘트 골조 건물에 적용하여 평가해 보았다. 평가는 일본건축방재협회에는 철근콘크리트 구조물의 내진성능평가 규준을 적용하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.513-523
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• 2012

The objective of this research is to examine how the lateral resisting system of selected prototypes are affected by seismic zone effect and shape irregularity on its seismic performance. The lateral resisting systems are divided into the three types, diagrid, braced tube, and outrigger system. The prototype models were assumed to be located in LA, a high-seismicity region, and in Boston, a low-seismicity region. The shape irregularity was classified with rotated angle of plane, $0^{\circ}$, $1^{\circ}$, $2^{\circ}$. This study performed two parts of analyses, Linear Response and Non-Linear Response History(NLRH) analysis. The Linear Response analysis was used to check the displacement at the top and natural period of models. NLRH analysis was conducted to invest base shear and story drift ratio of buildings. As results, the displacement of roof and natural period of three structural systems increase as the building stiffness reduces due to the changes in rotation angle of the plane. Also, the base shear is diminished by the same reason. The result of NLRH, the story drift ratio, that was subject to Maximum Considered Earthquake(MCE) satisfied 0.045, a recommended limit according to Tall Building Initiative(TBI).

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.4
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• pp.15-22
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• 2003

Seismic design codes developed taking into account the strong earthquakes may result in unnecessary economical loss in the low seismic area, and the importance of the performance based design considering the soil-structure interaction is recognized for the reasonable seismic design. In this study. elastic and inelastic seismic response analyses of a single degree of freedom system on the soft soil layer were performed considering the nonlinearity of the soil for the 1 weak earthquakes scaled to the nominal peak accelerations of 0.07g and 0.11g. The seismic response analyses were performed in one step applying the earthquake motions to the bedrock, utilizing a pseudo 3-D dynamic analysis software of the soil-structure system. The study results indicated that seismic response spectra of a system assuming the rigid base or the linear soil layer does not represent the true behavior of a structure-soil system, and it is necessary to take into account the nonlinear soil-structure interaction effects and to perform the performance based seismic design for the various soil layers, having different characteristics, rather than to follow the routine design procedures specified in the design codes for the reasonable seismic design. The nonlinearity of the soft soil excited with the weak seismic motions also affected significantly on the elastic and inelastic seismic response spectra of a system due to the nonlinear soil amplification of the earthquake motions, and it was pronounced especially for the elastic response spectra.