Sreten Mastilovic

Some fundamental issues of damage mechanics

The present paper focuses on the discussion of a set of rational criteria for the selection of the damage parameter. The paper considers scalar, second-, fourth-, and six-order tensor representations of damage and evaluates the accuracy with which they approximate exact, micromechanical solutions. Considerations of geometrical, stiffness and failure criteria favor the selection of effective stiffness as being the most appropriate choice for the damage parameter.

High-velocity expansion of a cavity within a brittle material

Analytical models of dynamic behavior of brittle materials subjected to large strain rates are often based on phenomenological constitutive laws deduced from macroscopic observations. The present study suggests that these laws can also be, in the absence of test data, deduced from the particle dynamics simulations. Simple, physically based laws governing the interaction between particles were found to be sufficient to replicate dominant aspects of the deformation. The continuum model based on these simulation data provided a realistic and accurate picture of the considered process.

Statistical models of brittle deformation: Part II: computer simulations

Abstract The second part of this study grew from the extensive work needed to identify the patterns and dominant aspects of the quasi-brittle response of solids subjected to high strain rates. The study also addresses the limits within the effective parameters and average fields of deterministic continuum models are representative measures of the thermodynamic state during a non-equilibrium, non-local and irreversible deformation.

Statistical models of brittle deformation Part I: introduction

Abstract The first part of this study focuses on the statistical mechanics underpinning of the lattice model and its relation to micromechanical and continuum models. The emphasis of the discussion is centered on the brittle and quasi-brittle deformations of materials with disordered microstructure and modest cohesive strength.

Brittle and quasi-ductile damage at large strain rates

The present study suggests that molecular and particle dynamics simulations can provide the basis for estimates of qualitative and quantitative aspects of damage in materials with inferior cohesive strength subjected to high strain rate loading. Two examples demonstrate that the traditional continuum models are of limited value in modeling of the class of considered problems.

Model of quasi-ductile deformations that bridges the scales

This study proposes a model of the deformation of materials susceptible to microcracking that is based on the thermodynamics of irreversible processes and fracture mechanics. The study considers the process on the atomic-, micro-, meso- and macroscales that are connected by the process of homogenization. The limitations of the process are carefully spelled out.