Recently, many people have become interested in seismic stability enhancement and a chain of research and development be proceed for application of nuclear power plant according to increase the frequency and magnitude of earthquake event. Such as seismic isolation system is applied to general structure (architecture, bridge and LNG tank etc.) from ancient times. But the application results is limited for Nuclear power plant. In this paper, we proposed a stability of variable axial load from beyond design basis earthquake in Nuclear power plant. Also, the change of stiffness in isolator from the application of generally design equation is not equal to according to change in axial load compare with the experimental result in variable axial load. Therefore we proposed the empirical formula of design equation from test result of full-scale multi-lead rubber bearing for seismic analysis with real behavior (variable axial load) in the earthquake motion.

1. 서 론
 2. 시험목적 및 개요
  2.1 시험목적
  2.2 시험체 제원 및 특성
  2.3 고무소재의 기계적 물성
  2.4 시험체 설계
  2.5 시험장비
 3. 특성평가
  3.1 시험항목
  3.2 기본 압축특성시험
  3.3 기본 전단특성 시험
  3.4 전단특성의 면압의존성 시험
 4. 면압의존성을 고려한 설계식 제안
 5. 결 론
 REFERENCES

• 장광석(유니슨이테크(주) 기술연구소 선임연구원) | Jang Kwang Seok
• 장준호(계명대학교 토목공학과 부교수) | Chang Chun Ho Corresponding author
• 이홍표(한국수력원자력 중앙연구원 플랜트건설기술연구소 선임연구원) | Lee Hong Pyo