Evaluation of the Soil-structure Interaction Effect on Seismically Isolated Nuclear Power Plant Structures

이은행,김재민,주광호,김현욱 한국지진공학회 2016 한국지진공학회논문집 Vol.20 No.6

This study intends to evaluate the conservativeness of the fixed-base analysis as compared to the soil-structure interaction (SSI) analysis for the seismically isolated model of a nuclear power plant in Korea. To that goal, the boundary reaction method (BRM), combining frequency-domain and time-domain analyses in a twofold process, is adopted for the SSI analysis considering the nonlinearity of the seismic base isolation. The program KIESSI-3D is used for computing the reaction forces in the frequency domain and the program MIDAS/Civil is applied for the nonlinear time-domain analysis. The BRM numerical model is verified by comparing the results of the frequency-domain analysis and time-domain analysis for the soil-structure system with an equivalent linear base isolation model. Moreover, the displacement response of the base isolation and the horizontal response at the top of the structure obtained by the nonlinear SSI analysis using BRM are compared with those obtained by the fixed-base analysis. The comparison reveals that the fixed-base analysis provides conservative peak deformation for the base isolation but is not particularly conservative in term of the floor response spectrum of the superstructure.

인문계 고등학교 특수교육 대상학생의 통합교육 활성화 방안

은행고등학교 국립특수교육원 2006 특수학급 컨설팅 시범학교 운영 보고서 Vol.2006 No.

㈜착한여행과 함께한 공정여행 이야기

이은행 사회적기업연구원 2011 사회적기업 Vol.22 No.-

KIESSI-3D 프로그램을 이용한 대형 3차원 SSI 해석

이은행,김재민,서춘교,Lee, Eun-Haeng,Kim, Jae-Min,Seo, Choon-Gyo 한국전산구조공학회 2013 한국전산구조공학회논문집 Vol.26 No.6

단단한 암반이 아닌 지반에 건설된 구조물의 지진응답을 정확하게 평가하기 위해서는 지반-구조물 상호작용(SSI)의 영향을 고려하여야 한다. 최근에는 USNRC SRP 3.7.2와 같은 원전설계분야의 규제지침 강화로 인해 SSI 해석의 필요성이 증가되고 있다. 이 연구에서는 대형 3차원 SSI 해석에 KIESSI-3D 프로그램을 사용한 사례를 제시하고 해석시간 및 정확성에 대한 토의를 하였다. 이를 위하여 대형 3차원 구조물 예제에 대한 SSI 해석을 수행하고 해석결과와 해석시간을 ACS/SASSI 프로그램과 비교하였다. 비교결과 KIESSI-3D 프로그램과 ACS/SASSI 프로그램에 의해 구한 구조응답의 전달함수가 거의 동일함을 보여 KIESSI-3D 프로그램의 정확성을 확인할 수 있었다. 아울러 해석시간 측면에서는 다중 쓰레드를 사용한 KIESSI-3D 프로그램(8개 쓰레드)이 단일 쓰레드를 사용한 ACS/SASSI 프로그램 보다 약 30배~2000배 빠른 성능을 보였다. The soil-structure interaction(SSI) effect should be considered to accurately assess the seismic response of structure constructed on soft soil site other than the hard bedrock. Recently, the demand of SSI analysis has increased due to strengthening of the regulatory guidelines of nuclear power plant such as the USNRC SRP 3.7.2. In this study an accuracy and running time of the KIESSI-3D program for large-scale 3D SSI analysis were investigated. The seismic SSI analysis using the KIESSI-3D program was performed for several examples of large-scale three-dimensional soil-structure interaction system. The analysis results were compared with those of the ACS/SASSI program. Good agreements in transfer functions at selected locations showd that KIESSI-3D yields accurate solution for large-scale SSI problem. Moreover, it was found that running speed of the KIESSI-3D for large-scale 3D SSI analysis is much faster than that of the ACS/SASSI about 30~2000 times.

지반-구조물 상호작용이 면진 원전구조물의 지진응답에 미치는 영향 평가

이은행,김재민,주광호,김현욱 한국지진공학회 2016 한국지진공학회논문집 Vol.20 No.6

This study intends to evaluate the conservativeness of the fixed-base analysis as compared to the soil-structure interaction (SSI) analysis for the seismically isolated model of a nuclear power plant in Korea. To that goal, the boundary reaction method (BRM), combining frequency-domain and time-domain analyses in a twofold process, is adopted for the SSI analysis considering the nonlinearity of the seismic base isolation. The program KIESSI-3D is used for computing the reaction forces in the frequency domain and the program MIDAS/Civil is applied for the nonlinear time-domain analysis. The BRM numerical model is verified by comparing the results of the frequency-domain analysis and time-domain analysis for the soil-structure system with an equivalent linear base isolation model. Moreover, the displacement response of the base isolation and the horizontal response at the top of the structure obtained by the nonlinear SSI analysis using BRM are compared with those obtained by the fixed-base analysis. The comparison reveals that the fixed-base analysis provides conservative peak deformation for the base isolation but is not particularly conservative in term of the floor response spectrum of the superstructure.

경계반력법을 이용한 지진격리 원전구조물의 비선형 지반-구조물 상호작용 해석

이은행,김재민,이상훈 한국지진공학회 2015 한국지진공학회논문집 Vol.19 No.1

This paper presents a detailed procedure for a nonlinear soil-structure interaction of a seismically isolated NPP(Nuclear Power Plant) structure using the boundary reaction method (BRM). The BRM offers a two-step method as follows: (1) the calculation of boundary reaction forces in the frequency domain on an interface of linear and nonlinear regions, (2) solving the wave radiation problem subjected to the boundary reaction forces in the time domain . For the purpose of calculating the boundary reaction forces at the base of the isolator, the KIESSI-3D program is employed in this study to solve soil-foundation interaction problem subjected to vertically incident seismic waves. Wave radiation analysis is also employed, in which the nonlinear structure and the linear soil region are modeled by finite elements and energy absorbing elements on the outer model boundary using a general purpose nonlinear FE program. In this study, the MIDAS/Civil program is employed for modeling the wave radiation problem. In order to absorb the outgoing elastic waves to the unbounded soil region, spring and viscous-damper elements are used at the outer FE boundary. The BRM technique utilizing KIESSI-3D and MIDAS/Civil programs is verified using a linear soil-structure analysis problem. Finally the method is applied to nonlinear seismic analysis of a base-isolated NPP structure. The results show that BRM can effectively be applied to nonlinear soil-structure interaction problems.

비선형 SSI 해석을 위해 Spring-Damper 에너지 흡수경계조건을 적용한 BRM의 유한요소 모델링 범위에 따른 응답평가

이은행,김재민,정두리,주광호 한국전산구조공학회 2016 한국전산구조공학회논문집 Vol.29 No.6

The boundary reaction method(BRM) is a substructure time domain method, it removes global iterations between frequency and time domain analyses commonly required in the hybrid approaches, so that it operates as a two-step uncoupled method. The BRM offers a two-step method as follows: (1) the calculation of boundary reaction forces in the frequency domain on an interface of linear and nonlinear regions, (2) solving the wave radiation problem subjected to the boundary reaction forces in the time domain. In the time domain analysis, the near-field soil is modeled to simulate the wave radiation problem. This paper evaluates the performance of the BRM according to modeling extent of near-field soil for the nonlinear SSI analysis of base-isolated NPP structure. For this purpose, parametric studies are performed using equivalent linear SSI problems. The accuracy of the BRM solution is evaluated by comparing the BRM solution with that of conventional SSI seismic technique. The numerical results show that the soil condition affects the modeling range of near-field soil for the BRM analysis as well as the size of the basemat. Finally, the BRM is applied for the nonlinear SSI analysis of a base-isolated NPP structure to demonstrate the accuracy and effectiveness of the method.

기초의 묻힘이 면진 원전구조물의 지진응답에 미치는 효과

이은행,김재민,이상훈,김재희 한국전산구조공학회 2016 한국전산구조공학회논문집 Vol.29 No.5

이 연구는 기초의 묻힘이 면진 원전구조물의 응답에 미치는 효과를 지표기초와 비교하여 평가하였다. 면진장치의 비선형 성을 고려한 비선형 SSI 해석은 진동수영역해석과 시간영역해석의 복합법인 경계반력법(BRM)을 이용하여 수행하였다. BRM 해석모델은 BRM을 이용한 등가선형 SSI 해석결과를 재래의 주파수영역 SSI 해석결과와 비교함으로 검증하였다. 마 지막으로 비선형 SSI해석에 의한 묻힌기초 모델의 면진장치의 변위 및 구조물 응답을 지표기초의 해석결과와 비교하였다. 비교결과, 면진장치의 변위응답은 묻힌기초효과를 고려할 경우 감소할 수 있음을 알 수 있었다. This study is aimed to evaluate the embedment effect of foundation as compared to the surface foundation on the response of a base-isolated nuclear power plant structure. For this purpose, the boundary reaction method (BRM), which is a two-step frequency domain and time domain technique, is used for the nonlinear SSI analysis considering nonlinear behavior of base isolators. The numerical model of the BRM is verified by comparing the numerical results obtained by the BRM and the conventional frequency-domain SSI analysis for an equivalent linear SSI system. Finally, the displacement response of the base isolation and the horizontal response of the structure obtained by the nonlinear SSI analysis using the moat foundation model are compared with those using the surface foundation model. The comparison showed that the displacement response of the base isolation can be reduced by considering the embedment effect of foundation.

保安處分의 基本理論에 관한 小考

은행표 광주대학교 1998 社會科學硏究 Vol.8 No.-

少年非行과 家庭環境

殷幸杓 광주대학교 1984 광주개방대학 논문집 Vol.1 No.-

The purpose of this study is to prevent the juvenile delinquency which is increasing in our societies and to devise a prepared countermeasure. The methods of this study were prepared as a result of a theoretical and bibliographical study, and a field survey. The field survey was conducted throgh personal interviews, and onsite observation as follows; some 100 students answered to complete questionnaires with the recovery-rate of 80%. Contents of questionnaires for students were composed of 13 items checking their personal thoughts. The group sampling was limited to the domestic junior and senior high school students. On the Juvenile Delinquency and Environments this paper attempt to study on the Juvenile delinguency and their environments. Juvenile delinguency has become a serious problem, as a pollution and a birth control in the societies. Recently, the rate of juvenile delinguency is increasing in the world despite differences in culture, economic conditions and government policies. Therefore there is a great need for special studies on the juvenile delinquency and its prevention. It is regarded that juvenile delinquency is one of the social phenomena which is related to the formation of core family and the materialistic consuming tendency which is a result of transmission of western culture. The scope of this study is limited to the analysis of juvenile delinquency in Korea, U.S.A. England, France, Austria and Switzerland. The contents of this study is composed of 5 chapters as follows ; Chapter Ⅰ is and introduction. Chapter Ⅱ deals with analyzing of the causes of juvenile delinquency in their personal and home environments. Chapter Ⅲ deals with the facts that broken home brought about juvenile delinquency. Chapter Ⅳ deals with the problems and the countermeasure of juvenile delinquency. Chapter Ⅴ is a conclusion.