This paper discusses the evaluation of the structural integrity of the SAFKEG radioactive material package to ensure hazardous material confinement during the postulated accident event of forklift truck collision. When a SAFKEG Package carried by a forklift truck traveling at 7 miles per hour collides with another forklift truck moving at the same speed but in the opposite direction, the structural response of the package components represents a complex problem. Because of its complex geometric configuration and complicated contact conditions between the neighboring component interfaces, the problem can not be solved using the implicit numerical scheme that would involve solving a large number of simultaneous equations through numerical iteration. In addition, material degradation and failure caused by collision can create severe convergence difficulties in the implicit analysis. Consequently, the explicit solution method is used in the present analysis, and thus the problem has to be treated as a dynamic one even though the inertia effect is insignificant due to the low speed of the forklift trucks. Applying the explicit dynamic technique to quasi-static problems involving very large deformation and material degradation require special considerations in overcoming solution convergence and extremely long computing time. The techniques used to overcome these difficulties are discussed in this paper. This paper also discusses the development of the constitutive models of the thermal insulating and shock absorbing materials used in the SAFKEG. The resin-bounded cork material is represented by the “crushable foam” plasticity with volumetric hardening. On the other hand, the material model of the brittle foam is developed by using the combination of the Mohr-Coulomb and Drucker-Prager plasticity theories. The analysis utilizes the finite-element method and the ABAQUS/Explicit Computer Code, version 6.3. A combination of the “General Contact” method and the “Contact Pair” method is employed to simulate the complicated interface variations among the neighboring components of the model.

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