• 방재와보험
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• s.60
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• pp.28-33
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• 1994

• 방재와보험
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• s.105
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• pp.14-19
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• 2005

• 방재와보험
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• s.127
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• pp.6-11
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• 2008

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.2098-2101
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• 2007

본 연구에서는 최근 5년간 서해에서 발생한 해저 지진 중에서 가장 큰 지진인 2003년 3월 23일에 발생한 해저 지진의 진앙지(북위 $35^{\circ}$, 동경 $124.6^{\circ}$)에 우리 나라에 가장 큰 피해를 입힌 1983년 동해 중부 지진해일의 지진 매개변수(parameter)를 적용한 가상 지진해일을 발생시키고 새만금 지역의 최대 처오름 높이를 계산하였다. 가상지진해일에 대한 수치모의 결과 새만금 지역에서는 $0.4{\sim}0.9m$의 파고가 발생하겠으며, 이러한 결과는 지진해일로 인한 새만금 방조제 유실 및 방조제 내부의 재난방재를 위한 기초적 자료가 될 것이다.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.3 s.22
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• pp.29-35
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• 2006

Fiber element method in earthquake response analysis of bridges is used to represents a realistic flexural deformation according to nonlinear behavior of beam-column section. Nonlinear pseudo-static analysis of two column bent using fiber element is accomplished and failure mechanism of the plastic hinge region is studied. Load-displacement curve obtained by nonlinear pseudo-static analysis can be applicable to earthquake response analysis by capacity spectrum method. The nonlinear time history analysis of a full bridge model using fiber element experienced by the ground motion corresponding to the target response spectrum is accomplished. The result of time history analysis is similar to that of capacity spectrum method.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.73-79
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• 2008

Economic growth, industrialization and urbanization have made society more vulnerable than ever to seismic hazard in Korea. Although Korea has not experienced severe damage due to earthquakes during the last few decades, there is little doubt of the potential for large earthquakes in Korea as documented in the historical literature. As we see no immediate promise of short-term earthquake prediction with current science and technology, earthquake early warning systems attract more and more attention as a practical measure to mitigate damage from earthquakes. Earthquake early warning systems provide a few seconds to tens of seconds of warning time before the onset of strong ground shaking. To achieve rapid earthquake location, we propose to take full advantage of information from existing seismic networks; by using P wave arrival times at two nearest stations from the earthquake hypocenter and also information that P waves have not yet arrived at other stations. Ten earthquakes in the Korean peninsula and its vicinity are selected for the feasibility study. We observed that location results are not reliable when earthquakes occur outside of the seismic network. Earthquakes inside the seismic network, however, can be located very rapidly for the purpose of earthquake early warning. Seoul metropolitan area may secure $10{\sim}50$ seconds of warning time before any strong shaking starts for certain events. Carefully orchestrated actions during the given warning time should be able to reduce hazard and mitigate damages due to potentially disastrous earthquakes.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2007.10a
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• pp.177-183
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• 2007

최근 증가하고 있는 자연재해 중 지진의 피해는 전체의 재해에서 차지하는 비중은 상대적으로 적지만, 빈도와 강도가 증가하고 있으며, 대응하기 위한 예측 체계가 거의 없다는 것이 어려운 점이다. 일본의 후쿠오카 지진 이후 내진설계 기준이 강화되고 있으나 실제지진발생시 최대가속도의 크기와 전파속도에 대한 이론적인 연구는 있었지만 국가적 차원의 자료 구축은 거의 없었다. 2005년 이후 소방방재청에서 지진대책사업단이 구성된 이후, 각 기관에 산재된 GIS 자료를 수집하여, 지진반응에 맞는 자료로 가공하고 프로그램으로 구현하게 되었다. anyguide 라는 지리정보도시 시스템과 Java 어플리케이션으로 구성된 프로그램을 통하여 과거의 지진자료와 측정지점에 대한 정보를 구축하였으며, 실제 지진발생 시에 지자체에서 대응할 수 있는 경보시스템을 동시에 구축하였다. 2007년 2월에 발생한 평창 주변의 지진발생시 시스템이 작동하여 3초내에 실제 shake map과 20초 이내에 hazard map이 작성되었으며, 실제 인명과 가옥 파괴 비율을 검증할 수 있었다. 2007년 말부터 2차 피해예측 추이 부분이 추가되어 보다 종합적인 대응시스템이 될 것으로 예상된다.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.7-13
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• 2011

Accurate response analysis of long span bridges subjected to seismic excitation is important for earthquake hazard mitigation. In this paper, the performance of a typical four span continuous reinforced concrete bridge model subjected to asynchronous multiple seismic excitations at the supports is investigated in both the time and frequency domains and the results are compared with that from a relevant uniform support excitations. In the time domain analysis, a linear modal superposition approach is used to compute the peak response values. In the frequency domain analysis, linear random vibration theory is used to determine the root mean square response values where the cross correlation effects between the modal and the support excitations on the seismic response of the bridge model are included. From the two sets of results, a practical range of peak factors which are defined to be the ratio of peak and the root mean square responses are suggested for displacements and forces in members. With reliable practical values of peak factors, the frequency domain analysis is preferred for the performance based design of bridges because of the computational advantage and the generality of the results as the time domain analysis only yields results for the specific excitation input.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.1
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• pp.112-119
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• 2021

The failure mode of piping systems due to seismic loads is the low-cycle fatigue failure with ratcheting, and it was found that the element in which nonlinear behavior is concentrated and damage occurs is the elbow. In this study, to quantitatively express the failure criteria for a pipe elbow of SCH40 3-inch carbon steel under low-cycle fatigue, the limit state was defined as leakage, and the in-plane cyclic loading test was conducted. For the carbon steel pipe elbow, which is the vulnerable part to seismic load of piping systems, the damage index was represented using the moment-deformation angle relationship, and it was compared and analyzed with the damage index calculated using the force-displacement relationship. An attempt was made to quantitatively express the limit state of the carbon steel pipe elbow involving leakage using the damage index, which was based on the dissipated energy caused by repeated external forces.

• Journal of Korean Association for Spatial Structures
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• v.21 no.2
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• pp.57-66
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• 2021

This study develops finite element models for seismically-deficient reinforced concrete building frame retrofitted using fiber-reinforced polymer jacketing system and validates the finite element models with full-scale dynamic test for as-built and retrofitted conditions. The bond-slip effects measured from a past experimental study were modeled using one-dimensional slide line model, and the bond-slip models were implemented to the finite element models. The finite element model can predict story displacement and inter-story drift ratio with slight simulation variation compared to the measured responses from the full-scale dynamic tests.