[en] Dynamic response of LMFBR primary containment to the hypothetical explosive accident is discussed. The amount of experimental and analytical effort given to the problem in Czechoslovakia is presented. The experimental program consists of a sequence of tests using models of increasing complexity in fast reactor primary structure. As the energy source, high explosives are used. The response of reactor materials subjected to dynamic load is investigated on an experimental facility based on Hopkinson-Davies bar which makes possible to study the influence of strainrate, temperature and irradiation on material properties. Theoretical effort of the Power Research Institute is based on the mechanistic approach. For the initial phase of the hypothetical accident, the programme SASIA was adopted. The course of nuclear excursion is solved by the TWEXCO code. Dynamic response of fast reactor primary containment to the core disruptive accident is treated by the CEFRA code. Both programmes are two-dimensional (r-z) Lagrangian hydrodynamic codes. They treat the media under consideration as compressible, inviscid and non-heat-conducting fluids. Hydrodynamic equations and equations of state of reactor materials are used for the calculation of the shock waves propagation, the damage produced by these loads and the motion of coolant. They used plate-shell equations to determine the dynamic response of the reactor containment. Containment materials may be elastic-plastic, strain hardening and strain-rate sensitive. The plug and cover are treated as rigid-body model. The validity of the codes performance has been verified through experiments. Some results of this comparison and application to a 600MWe fast reactor project are presented