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This paper focuses on addressing seismic safety evaluation and resilience analysis of nuclear containment structure. Through the derivation of fragility formulas and the introduction of a new set of limit states (LSs), this paper accomplishes the fragility analysis and assesses failure probabilities comprehensively. Furthermore, safety evaluation and resilience analysis procedures, specifically for nuclear containment, are proposed alongside relevant determination criteria. In order to further improve the seismic performance of nuclear containment, the periodic foundation is analyzed. Theoretical formula is derived to determine the combination of 2 materials (concrete and rubber). Key findings include the safety demonstration of HUALONG 1 through probabilistic reliability analysis, the safety level (Level-I; basic integrity) and resilience level (Level-I). The effectiveness of periodic foundations is confirmed and supported by the average damping rates of concrete and liner strains, which can reach up to 6.154 % and 11.007 %, respectively. This research provides valuable insights for improving the seismic safety and resilience of containment, crucial for ensuring the integrity and functionality of this critical infrastructure system. [ABSTRACT FROM AUTHOR]

In order to solve the shortcomings of fragility analysis by finite element method, this paper proposes a method for calculating the structural fragility of nuclear containment under the loading of inner pressure (which is abbreviated as "inner pressure fragility") based on a simplified calculation method and related program (coded by Python) named as NCMC. This enables direct preliminary screening to delete unsuitable nuclear containment types that cannot meet the required failure probability. In addition, this paper conducts a detailed parameter analysis on factors such as concrete thickness and material type, liner thickness, and the numbers of tendons and rebars in the hoop and vertical directions. By analyzing the changes in failure probability due to parameter changes, based on confirming the safety margin and load bearing capacity of the original nuclear containment type, suggestions for parameter choices are provided for a certain containment. The same method and analyzing routine can also be used for realizing fast parameter selection for other structures. [ABSTRACT FROM AUTHOR]

• Three rocking steel frames are comparatively tested and modelling method is proposed. • The effectiveness of beam-column joint with reduced beam section is analyzed. • The effectiveness of buckling-restrained brace used in rocking structure is analyzed. • Semi-rigid joint is superior to rigid joint in tested rocking structures. A rocking steel frame is proposed in this paper, which can reduce the plastic deformation of the main structural components under strong earthquake actions and can be easily repaired after earthquakes. Three 1:2 testing steel frames (buckling-restrained braced steel frame, rocking steel frame with rigid beam-column joint and rocking steel frame with semi-rigid beam-column joint) are designed and manufactured. The pseudo-static tests on the three specimens are carried out respectively. The hysteretic curves, skeleton curves, stiffness degradation rules and other parameters of the three specimens are compared and analyzed to study the seismic performance and damage characteristics of the rocking steel frame. The effect of beam-column joint form on the seismic performance of the rocking steel frame is investigated. In addition, the corresponding numerical analysis and modelling methods are introduced. The results indicate that the rocking structure can effectively reduce the damage of beams and columns. The RBS (rigid beam-column joint with reduced beam section) on the beam end can effectively transfer plastic hinge to the beam end, thus protecting the beam-column joints. It can be also concluded from the results that compared with rigid beam-column joint, semi-rigid beam-column joint has greater superiority and better seismic performance, which can protect the main components more effectively. [ABSTRACT FROM AUTHOR]