Thermo-mechanical processes, which develop in deformable solids under intensive dynamic loading, consist of mechanical, thermal and structural ones, which correlate themselves. These processes develop as irreversible deformations, strips of adiabatic shear and microfacture. Dynamic fracture is a complicated multistage process including the stages of initiation, growth and merging of microdefects, the formation of embryonic microcracks, pores, that grow leading to the break-up of the bodies resulting in their fragmentation. The present paper include new results on the following aspects: ? development of the thermodynamically adequate mathematical models of damageable thermoelastoviscoplastic media (microfracture); ? development of the methods for determination of «nonstandart» constants of medium models, connected with microfracture of materials; ? numerical simulation of failure (fragmentation) of structures (macrofracture); ? numerical investigation of applied problems for damageable solids and structures (dynamical deforming and fracture of thick-walled cylindrical and spherical shells under explosion; dynamical deforming and fracture of thick-walled two-layer shell, filled with liquid, under external impact loading; the problems of dynamic deformation and failure of an oil-holding layer in hydraulic fracturing; dynamics of irreversible deforming and fracture of oil-bearing layer when abruptly releasing the load on borehole surface etc.).
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