This paper presents the performance improvement of an EQS (Eradic Quake System) device applied to a nuclear power plant. For the nuclear facility, the EQS device needs to be ensured to have high quality, flexibility of design and reliability. To improve the reliability of the design, the hysteresis of the device must be exactly predicted. The friction coefficient of PTFE (PolyTetraFluoroEthylene) and the stiffness of the MER-Spring are considered as the factors influencing the hysteresis curve. In this paper, those factors are analysed to predict the behavior of the device and to improve the equipment of the EQS device. The results of the improved EQS device have been verified via a tests to be comparable with the predicted results. The estimation results indicate that considering those factors is more appropriate than the results of the previous design and method.

본 논문에서는 면진시스템이 원전에 적용될 경우 원전구조물의 생애주기 성능에 미치는 영향을 소개한다. 최근 내진설계와 더불어 강진발생 예상 지역에 적용을 목적으로 개발되는 면진시스템은 구조물을 장주기화하여 응답가속도를 줄이고 상대변위를 늘려줌으로써 구조물의 안전성을 증진시키는 것으로 알려져 있다. 따라서, 구조물의 안전성이 중요시되는 원전구조물에 면진시스템을 적용하기 위한 연구가 국내에서 진행 중에 있다. 본 연구에서는 원전구조물의 생애주기 성능분석에 있어서 특징을 분석하고, 면진시스템이 적용될 경우 원전구조물의 생애주기성능에 있어서 미치는 영향을 평가함으로써, 도출된 결과를 면진시스템 적용의 정량적인 타당성 평가에 활용할 수 있다.

원전 격납건물은 프리스트레스 콘크리트 구조로 사고발생시 내부의 방사능물질이 외부로 유출되지 않도록 강재 철판을 내 측 콘크리트 면에 설치하여 압력경계를 유지하고 있다. 강재 철판은 건설시에는 콘크리트 거푸집이고 가동중에는 차폐역할 을 하게 된다. 최근 가동원전 격납건물 라이너플레이트에 일부 부식이 발생된 사례가 있는데 공칭두께 대비 10% 이상의 두께 감육부는 공학적 평가를 통해 계속사용 또는 교체를 한다. 본 논문에서는 공학적 평가를 위한 구조해석 모델 개발 시간 단축을 위해 라이너플레이트의 설계조건과 형상을 고려한 자동화시스템을 개발하였다.

There are two kinds of post-tensioning system for nuclear power plants. one is bonded-type and the other is unbonded-type post-tensioning system. It is difficult to directly evaluate the effective tensile force of tendon in the case of bonded-type. Therefor, it can be evaluated by system identification(SI) method. In order to use SI technique, it should be obtained the strain measurement results of the containment building wall. This paper is mainly focused on the stain measurement according to the internal pressure of containment building using fiber optic sensor and tried to use it as a basic data of the SI technique in the future.

Recent earthquakes in Gyeong-ju and Po-hang have raised concerns about the safety of nuclear power plant structures. In particular, there is a demand for a technique for detecting and evaluating the deterioration that occurs in the concrete which is inaccessible after curing. In this paper, we propose a method for evaluating the reliability of concrete detection equipment using ultrasound, as the ultrasonic tomography technique has been attracting much attention with the detection technique of the inside of concrete.

Based on the study of strength development characteristics of Ground granulated blast-furnace slag(GGBFS), it was found that the use of GGBFS as a admixture was advantageous in terms of long-term strength. Therefore, GGBFS can be a replacement for the Flyash which is currently used in the NPP.

In this study, Lead Rubber Bearing(LRB) characteristics calculated by the design of the seismic isolation system, according to the seismic isolation structure with the application of nuclear power plants. Experiments were carried out to analyze the compression characteristics of prototype LRB under variable shear displacement.