Performance Rating Standards for Anti-Ram Bollards in Nuclear Facilities based on LS-DYNA Analysis

In recent years, the demand for robust physical protection for nuclear power plants has intensified, leading to the inclusion of vehicular threats in the design basis threat (DBT) for nuclear facilities after the 2016 Nice attack. Despite this requirement, a significant portion of bollards currently deployed at domestic nuclear power plants and critical infrastructure lack formal performance certification. Most are designed for pedestrian safety or traffic management rather than high-velocity impact resistance, resulting in inadequate energy absorption capacity. Furthermore, existing international certification frameworks, such as ASTM F2656, rely primarily on full-scale crash tests, which are prohibitively expensive and lack the flexibility to account for diverse site-specific conditions. To address these challenges, this paper presents an objective methodology for evaluating the performance of concrete-filled bollards using LS-DYNA numerical analysis as a viable alternative to physical testing. Utilizing the data derived from these simulations, we establish a new performance rating system (Categories A, B, and C) based on vehicle penetration for varying impact velocities. This research provides a foundational framework for the performance based standardization of vehicular barriers, facilitating the enhancement of physical security protocols for domestic nuclear facilities.