Numerical Simulation of the Dynamic Loading Process of Initially Damaged Media.

This work is connected with the problem of the dynamic loading of initially damaged media. The deformable solid medium with a complex internal structure is considered. The process of fracturing can drastically decrease the material stiffness and affect the wave propagation process. The continuum model of solid media with a discrete set of slip planes and nonlinear viscous-plastic contact conditions on them is formulated. It allows to simulate the dynamic behavior of complex media, like composite materials or geological fractured massifs. For a stable numerical solution of a system of differential equations, an explicit-implicit method is derived with an explicit approximation of motion equations and an implicit approximation of the constitutive relations containing a small parameter. To achieve a high precision, the hyperbolic part is solved with the grid-characteristic method on rectangular grids. In this research we compared simulated wavefields with the same ones obtained by the method of explicitly setting crack positions. The results can be useful for the problem of the low impact damage estimation. [ABSTRACT FROM AUTHOR]