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The computer simulation of the propagation of a blast wave generated by various explosives is carried out. The simulation used numerical methods to solve dynamic problems in the mechanics of a deformable solid, which allow one to investigate the development of waves during the explosion of charges of various shapes at different speeds of detonation of explosives and various conditions of placement of charges in the hole. The novelty of the research is related to analysis of conditions for the formation of a tensile pulse, which determines the opening of natural and induced defects in a zone remote from the explosion (from 20 to 100 radii of charge), which is known as the zone of explosive pre-fracture. [ABSTRACT FROM AUTHOR]

In the present study, using the molecular dynamics method, we investigated the impact interaction of a spherical cluster of 3C-SiC silicon carbide with a rigid wall at a wide range of velocities. The influence of cluster initial temperature on the fracture process was analyzed. [ABSTRACT FROM AUTHOR]

In many fracture problems, fragmentation is essentially a probabilistic process, which is determined by the stochastic nature of the distribution of inhomogeneities of the internal structure of material. The probabilistic approach is described, which allows us to model structural heterogeneities of the material in a simple form, practically without any complication of the model and additional experiments. Using experimental data and numerical simulation results, it is shown that the introduction of only one additional parameter (dispersion of the strength properties distribution) into the material model makes it possible to give a probabilistic character to the crack formation process at any scale level, which corresponds to theoretical concepts and experimental data. Distribution of materials strength characteristics (according to the selected distribution law) in the cells of the computational domain is used for initial heterogeneities and materials structure defects modeling. It is shown that the number and size of the "petals" at the penetration of thin barriers depend of the speed of the projectile and the strength characteristics of the barrier. [ABSTRACT FROM AUTHOR]

The article shows studies of bending basalt fiber reinforced concrete elements with pre-stressed glass composite reinforcement under static and short-term dynamic effects. Main results of numerical and experimental studies are presented. It is experimentally established and theoretically confirmed that a significant increase in the strength and crack resistance of the normal sections of concrete bent elements is observed when using basalt fiber reinforcement and pre-stressed glass composite reinforcement. [ABSTRACT FROM AUTHOR]

Based on the hybrid numerical method, namely, the hybrid method of movable cellular automata, we developed a computer-based two-scale mechanical model of heavy water-saturated concrete. The model takes into account the content of the liquid phase and its redistribution in networks of microscopic and capillary pores. The features of deformation and fracture of concrete samples under uniaxial compression were numerically studied in a wide range of variation of the macroscopic characteristics of the pore space, viscosity of an interstitial liquid and loading rate. Simulation results confirmed the possibility of a unified description of the dependence of the strength of heavy concrete on the sample permeability and size, fluid viscosity and the loading rate in terms of the complex dimensionless parameter that combines these characteristics. [ABSTRACT FROM AUTHOR]

Deformation and fracture of metal-ceramic composites and coatings under quasistatic tension, compression, shear, and during cooling from the melt to room temperatures are numerically investigated. Dynamic and quasistatic boundary-value problems are solved in twoand three-dimensional formulations by the finite-difference and finite-element methods. Constitutive models include the isotropic hardening of aluminum and fracture of ceramic particles. Composite microstructure is taken into account explicitly. Analysis of the fracture in composites is carried out, with the residual stresses being not taken into consideration. Origination of cracks in the near-interface regions of bulk tension and their propagation in ceramic particles are investigated. Residual stresses formed during cooling of the composites are calculated for different volume fractions of particles. [ABSTRACT FROM AUTHOR]

A theoretical study of the deformation and fracture behavior of Ni3Al alloy under shock loading has been carried out. The finite element method simulation was used within the approach that combined modeling in terms of the dislocation kinetics of alloys with the L12 superstructure and the mechanics of a deformable solid. The dislocation kinetic model of the alloys with the Ll2 superstructure defined the hardening of Ni3Al punch and plate materials, while the model of the mechanics of a deformable solid described deformation of the macrovolume. [ABSTRACT FROM AUTHOR]

The paper presents results of applying approach to simulation of contact surfaces fracture under high velocity interaction of solid bodies. The algorithm of erosion -the algorithm of elements removing, of new surface building and of mass distribution after elements fracture at contact boundaries is consider. The results of coordinated experimental and numerical studies of fracture of materials under impact are given. Authors own finite element computer software program EFES, allowing to simulate a three-dimensional setting behavior of complex structures under dynamic loads, has been used for the calculations. [ABSTRACT FROM AUTHOR]