A study on the resistance of SC walls subjected to missile impact using large-scale impact tests

Abstract

Nuclear power plants (NPP) should resist local impact loads such as aircraft engine impact as well as internal and external missile impacts based on the international regulations for NPP structures. Although a wide variety of studies on the local responses of conventional reinforced concrete (RC) walls under impact loading have been performed and the design methods for preventing local failure are previously established, no appropriate design methodology is available for steel-plate concrete (SC) walls except for that recently cited in AISC N690 specifications. In this paper, the local resistance and behavior of SC walls subjected to missile impact were investigated experimentally. A total of ten large-scale impact tests for SC and RC walls were performed. The SC wall specimens were designed using various parameters including wall thickness and steel-plate thickness (reinforcement ratio). A set of RC wall specimens were designed for comparison. Initial and residual velocities of projectile, strain and acceleration of the rear plate, local failure mode and deformation, etc. were measured utilizing high speed cameras and various instrumentation devices. From this study, the actual local impact behaviors of SC walls were investigated and the quantitative impact resistance was evaluated. Overall, the current AISC N690 design method was somewhat conservative and needs to be improved for beyond-design-basis events such as aircraft engine impact.