EVALUATION OF A MASSIVE AIRCRAFT IMPACT WITH A VERTICAL CONCRETE CASK

Accident scenarios for the storage environment of spent fuel are described in Standard Review Plan 1567, but the interest in additional threats has markedly increased. A threat of significant interest is the impact of a large aircraft with the storage overpack, which is maintained outside the confines of the reactor building. The confinement boundary for the fuel is a stainless steel canister, which is protected by the vertical reinforced concrete cask (VCC). The scenario of a VCC impacted by a Boeing 747 airplane at 500 mph is presented in this evaluation. The VCC is assumed to be positioned on a concrete pad and is loaded with a canister containing spent fuel. The evaluation considers two impacts. The first impact occurs when the airplane collides with the VCC causing the VCC to tip-over and slapdown onto the concrete pad. The second impact occurs when the canister impacts the inner surface of the VCC. LS-DYNA is used to perform the evaluations, which confirms that the canister will maintain confinement after the accident.