• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.194-201
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• 2000

In this study the modified seismic coefficient method for seismic analysis of buried box structures is developed for practical purpose. The loading coefficient in the modified seismic coefficient method is determined from the results of the response displacement analysis. In the developed method adequate velocity response spectrum in accordance with soil condition is also needed to seismic design of buried box structures, In order to investigate applicability of the modified seismic coefficient method various analyses are performed with different parameters such as depth of base rock height and width of box buried depth and value of standard penetration test. Results from the modified seismic coefficient method are compared with those of the response displacement method in terms of the maximum bending moment and the location of it. From the comparison it is shown that the feasibility of the modified seismic coefficient method for seismic analysis of buried box structures.

• 한국지진공학회논문집
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• 제7권5호
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• pp.1-9
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• 2003

국내 콘크리트댐의 경우 내진설계는 관성력을 고려한 진도법을 적용하여 설계를 하고 있으나, 보수적인 설계 방법으로 동적특성을 반영하지 못하는 단점이 있어, 동적특성을 고려한 댐 내진설계가 필요하다. 또한 콘크리트댐 내진성능평가는 동적해석으로 평가해야 하지만, 국내의 경우 대부분 진도법으로 평가를 하고 있어 현행 기준을 적용하기에는 어려운 점이 있다. 이에 본 연구에서는 진도법, 수정진도법, 동적해석 방법을 수행하여 내진설계 및 내진성능평가 결과에 대해서 비교 분석하였다.

• Nuclear Engineering and Technology
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• 제53권3호
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• pp.967-973
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• 2021

In 2011, an earthquake and subsequent tsunami hit the Fukushima Daiichi Nuclear Power Plant, causing simultaneous accidents in several reactors. This accident shows us that if there are several reactors on site, the seismic risk to multiple units is important to consider, in addition to that to single units in isolation. When a seismic event occurs, a seismic-failure correlation exists between the nuclear power plant's structures, systems, and components (SSCs) due to their seismic-response and seismic-capacity correlations. Therefore, it is necessary to evaluate the multi-unit seismic risk by considering the SSCs' seismic-failure-correlation effect. In this study, a methodology is proposed to obtain the seismic-response-correlation coefficient between SSCs to calculate the risk to multi-unit facilities. This coefficient is calculated from a probabilistic multi-unit seismic-response analysis. The seismic-response and seismic-failure-correlation coefficients of the emergency diesel generators installed within the units are successfully derived via the proposed method. In addition, the distribution of the seismic-response-correlation coefficient was observed as a function of the distance between SSCs of various dynamic characteristics. It is demonstrated that the proposed methodology can reasonably derive the seismic-response-correlation coefficient between SSCs, which is the input data for multi-unit seismic probabilistic safety assessment.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2000
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• pp.108-115
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• 2000

Numerical analysis of slop stability is presented using seismic displacement, response seismic coefficient, and earthquake response analysis methods. In seismic displacement and response seismic coefficient methods, horizontal static seismic force is considered as 0.2g while vertical static seismic force is not considered in analysis. For earthquake response analysis Hahinoha-wave is applied, It is found from result that analysis using response seismic coefficient method is much more conservative than that using seismic displacement method Also, analysis result using earthquake response analysis method is somewhat less conservative about 25% when compared with that using seismic displacement method.

• Spatial Information Research
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• 제20권1호
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• pp.39-45
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• 2012

지진하중을 받는 건축물의 반응은 고유주기에 따라 다르게 나타난다. 국내 건축구조기준에서는 고유주기에 따른 지진응답계수를 규정함으로써 건축물의 내진설계를 하도록 하고 있다. 최근 많은 연구자들에 의하여 건축물의 고유주기, 지진응답계수에 대한 많은 연구가 이루어졌으나, 지리정보시스템(GIS)을 이용한 내진설계에 관한 연구는 미흡한 실정이다. 따라서 본 연구에서는 입체적인 3차원 공간에서 고유주기에 따른 지진응답계수를 비교 및 검토함으로써 구조물의 내진성능에 대한 분석을 효율적으로 평가할 수 있으며, 지리정보시스템(GIS)을 이용하여 합리적인 내진설계를 할 수 있는 기초 자료로 사용될 것이라고 기대된다.

• 한국지진공학회논문집
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• 제20권2호
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• pp.125-134
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• 2016

In order to improve seismic safety of nuclear power plant (NPP) structures in high seismicity area, seismic isolation system can be adapted. In this study, friction pendulum system (FPS) is used as the seismic isolation system. According to Coulomb's friction theory, friction coefficient is constant regardless of bearing pressure and sliding velocity. However, friction coefficient under actual situation can be changed according to bearing pressure, sliding velocity and temperature. Seismic responses of friction pendulum system with constant friction and various velocity-dependent friction are compared. The velocity-dependent friction coefficients of FPS are varied between low-and fast-velocity friction coefficients according to sliding velocity. From the results of seismic analysis of FPS with various cases of friction coefficient, it can be observed that the yield force of FPS becomes larger as the fast-velocity friction coefficient becomes larger. Also, the displacement response of FPS becomes smaller as the fast-velocity coefficient becomes larger.

• 한국지반공학회논문집
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• 제26권3호
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• pp.47-57
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• 2010

Newmark 활동블록법을 이용하여 지진시 토사면의 영구변위를 산정할 경우 항복지진계수의 결정은 매우 중요하다. 그러나 기존에 제안된 항복지진계수는 일반적으로 한계평형해석에 기초하고 있어 역학적조건 중 평형조건만을 만족하므로 역학적으로 엄밀하지 못하다. 따라서 기 제안된 항복지진계수를 이용하여 토사면의 영구변위를 산정할 경우 문제점를 야기할 수 있다. 한계해석은 역학적으로 엄밀한 해의 범위를 산정하는 해석기법으로 항복지진계수의 역학적 엄밀성을 판단하는데 유용하다. 본 연구에서는 안정수, 사면경사, 지반물성 등에 따른 다양한 해석조건을 고려하여 실무적용에 유용한 항복지진계수 산정도표를 제안하였다.

• 지질공학
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• 제30권2호
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• pp.175-184
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• 2020

국내에서는 비탈면을 대상으로 유사정적해석 시 수평 지진계수에 대한 적용 규정과 적용 사례들이 많이 있지만 연직 지진계수에 대한 규정이나 사례는 미비한 실정이다. 본 연구에서는 연직 지진계수의 영향도를 검토하고자 단양군 단양읍 ◯◯리를 대상으로 현장조사 및 실내시험을 수행하고, 이를 반영하여 무한사면 안정해석 기반의 유사정적 사면안정해석을 수행하였다. 분석 결과 지진규모가 5 이하인 경우에는 연직 지진계수의 영향이 거의 없는 것으로 분석되며, 지진규모가 6 이상인 경우에는 연직 지진계수가 안전율 1.1 이하의 불안정 영역을 크게 증가시키는 것으로 나타난다. 이러한 경향은 강우가 없는 조건보다 강우가 있는 조건에서 더욱 뚜렷하게 나타난다.

• 한국농공학회지
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• 제33권4호
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• pp.105-120
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• 1991

This study was performed to investigate the minimum safety factor of embankment in consideration of seismic coefficient by the psuedo-static analysis The variables were cohesion, the internal friction angle, angle of slope, height of seepage, height of embankment, depth of replacement The results obtained were compared with those by Fellenius method, simplified Bishop method and Janbu method. The results were summarized as follows: 1.The increasing rate of the minimum safety factor with the increasing of cohesion appeared larger in Fellenius method and Bishop method than in Janbu method. And that with the increasing of the internal friction angle appeared the lowest value in Janbu method. The minimum safety factor was influenced larger on the internal friction angle than on cohesion. 2.The variation of the minimum safety factor with the height of seepage at 0m and 5 m was nearly similar to Fellenius method, Bishop method and Janbu method. On the other hand, it was decreased suddenly at 25 m. 3.The minimum safety factor with the height of embankment was decreased remarkably under 10 m with the increasing of seismic coefficient. But, it was decreased slowly more than 10 m. As the height of embankment was low, the influence of cohesion appeared larger. 4.In heigher case of the depth of replacement, the phenomenon of reduction of the minimum safety factor appeared remarkably with seismic coefficient increased. And in lower case of the depth of replacement, the minimum safety factor was similar in Fellenius method and Bishop mehtod. But it appeared larger in Bishop method and Janbu method than in Fellenius method with the depth of replacement increased. 5.As the cohesion and the internal friction angle were large, the phenomenon of reduction of the minimum safety factor with the increasing of seismic coefficient appeared remarkably. Also, the influence of seismic coefficient in minimum safety factor appeared larger with the soil parameter increased. 6.When the seismic coefficient was considerated, investigation of the structural body on the slope stability appeared profitably in Fellenius method and Janbu method than in Bishop method.

• 한국터널지하공간학회 논문집
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• 제22권3호
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• pp.311-321
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• 2020

본 연구에서는 쉴드 터널 세그먼트 라이닝의 한계상태설계 시 세그먼트 라이닝에 작용하는 지진하중에 대한 변동계수를 산정하였다. 지반 정수의 통계적 특성치는 국내 지반의 확률특성치를 분석하여 단위중량에 대한 통계적 특성치를 산정하였으며, 전단탄성파 속도를 산정하기 위해 N값과 확률 특성치를 이용하였다. 지진하중 효과에 대한 변동계수를 산정하기 위하여 MCS기법을 적용하였으며, 지진하중 효과 산정에는 closed-form식을 적용하였다. 변동계수 산정결과, 풍화토 지반에서 지진하중 효과의 변동계수는 0.06~0.15의 범위로 분석되었고, 변동계수는 지진을 고려한 쉴드 터널의 한계상태설계 시 기본자료로 활용할 수 있을 것으로 판단된다.