Vibration analysis of third generation nuclear power plant considering soil‐structure‐interaction effect under the impact of large commercial aircraft

Abstract

Despite the rapid development of nuclear power, the risk of unforeseen beyonddesign-basis events has become a major concern for nuclear power plant (NPP) operators such as malicious aircraft impacts (AIs). This paper aims to perform vibration analysis on a Generation III NPP subjected to a large commercial aircraft crash, considering soil-structure-interaction (SSI) effect. Based on the verified finite element (FE) models of the aircraft Airbus A340 and the NPP, the whole collision process is reproduced numerically by adopting the missile-target-interaction method. The selection of soil type was based on AP1000 six-design soil sites, and five of which were selected for this study. The effect of impact direction, impact height, and embedment is also considered. Results showed that the soil type has a significant effect on the vibration response of points on the base-mat. Generally, the flexibility of soil increases the response of these points. In the process of propagation, the more flexible the soil is, the faster the weakening range will be. Different impact location will have great influence on the AI-induced vibration intensity of some areas of the NPP, such as the base-mat in the shield building. Increasing embedded depth reduces the response of points on the base-mat.

Research on the Value of Rayleigh Damping Parameter in Explicit and Implicit Integrals for Dynamic Analysis of Large Structures

“…In the above formula, L m is the maximum grid size in the foundation, V s is the shear wave speed of the foundation, f n is the Nyquist frequency, and a is a constant between 5 and 10. The shear wave speed of the foundation material was 1067 m/s, the shear modulus was 2.845 GPa, the density was 2500 kg/m 3 , and the Poisson's ratio was 0.2 [39,44]. Therefore, the foundation grids were all less than 6 m. Based on the literature [43,44], the foundation size was taken as 220 m × 200 m × 40 m.…”

“…The shear wave speed of the foundation material was 1067 m/s, the shear modulus was 2.845 GPa, the density was 2500 kg/m 3 , and the Poisson's ratio was 0.2 [39,44]. Therefore, the foundation grids were all less than 6 m. Based on the literature [43,44], the foundation size was taken as 220 m × 200 m × 40 m.…”