A set of equations of dynamic deformation and failure is formulated for low-plastic brittle-fracture media, such as concrete, ceramics, rocks and semi-rocks with three limiting surfaces: the initial yield surface, the failure surface, and the flow surface of the fully fragmented material. For the stressed-strained states on the yield surface, the stress-strain tensor relation is described by Hook's law. Deformation over the elastic strength limit is described using the relations of the associated theory of elastoplastic yielding. The elastoplastic deformation causes transformation of the initial yield surface and damage accumulation. The damage is summed up, accounting for the dependence of the damage function on the rigidity parameter of the stressed state, the type of the stressed-strained state and strain rates. The experimental data and empiric relations are compares with the results of computational experiments on the penetration of rigid strikers into bulk concrete and marble with various impact velocities.
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