A Practical Approach to Structural Evaluation of Radioactive Waste Transport Containers Using Strain Limits Based on Stress Triaxiality

Jongmin Lim^1,*, Yun-young Yang¹, Hoseog Dho², Hyungoo Kang², Sang Soon Cho¹

¹Korea Atomic Energy Research Institute, 111, Daedeok-daero 989beon-gil, Yuseong-gu, Daejeon 34057, Republic of Korea
²Korea Radioactive Waste Agency, 174, Gajeong-ro, Yuseong-gu, Daejeon 34129, Republic of Korea

Received 2025-02-24 ; Revised 2025-03-26 ; Approved 2025-05-02

Abstract

This study introduces a strain limit-based evaluation method that considers stress triaxiality to assess the structural integrity of radioactive waste transport containers. Unlike conventional stress-based approaches, this method provides a more precise assessment of localized plastic deformation and damage. By incorporating strain-based failure criteria, it enables a realistic evaluation of impact-induced deformation under complex stress states. A post-processing program is developed to intuitively verify strain safety margins, improving assessment accuracy. Additionally, sub-modeling techniques refined the strain distribution analysis in damage-concentrated areas, which could not be captured in full-scale simulations. This enhances the reliability of impact evaluations. Based on these procedures, a drop safety verification process was established for the freight container used in low- and intermediate-level waste transport. The results demonstrated the feasibility of strain limit-based evaluation in practical applications. This approach improves the structural assessment of transport containers and contributes to the advancement of design and certification processes.

Key Words : Transport container, Radioactive waste, Drop test, Stress triaxiality, Strain limit