Can a three-barrier steel side-shell structure design offer sufficient ship collision resistance for SMR-powered vessels?

Paper in proceeding, 2026

Some segments of the shipping industry are exploring the pros and cons of using small modular reactor (SMR) technology as the power source to reduce ship emissions. However, the introduction of SMRs in merchant ships may impose stricter regulations on ship structure arrangements regarding ultimate limit and accidental limit states. The current study emphasizes the accidental limit state by examining the crashworthiness of a candidate ship’s structural design through finite element (FE) simulations using Abaqus/Explicit to analyze ship-to-ship collision events. A selected reactor compartment is assumed to be passively protected by a reinforced side-shell structure made of steel, maximizing energy absorption in the event of a ship collision without penetration of the innermost side-shell barrier. The structural design is referred to as the three-barrier structure. Results from different collision scenarios are compared for three structural concepts: a conventional side-shell structure, the proposed three-barrier structure, and the well-known X-core structure. Performance is evaluated in terms of penetration depth before the innermost side-shell structure fractures, and total energy absorption. Among the structures that were compared, thethree-barrier structure demonstrated the greatest energy absorption capacity at high collision speeds, and it provided the best energy distribution between the striking ship
and the struck ship.