NONEQUILIBRIUM STATISTICAL-THEORY OF INHOMOGENEOUS DAMAGE

The shortcomings of Continuum Damage Mechanics (CDM) are discussed and nonequilibrium statistical physics is used to establish a new statist ical theory of inhomogeneous damage. The growth of microscopically dam aged regions (cracks, voids, etc.) is regarded as the elementary proce ss of damage to the material structure and the damage parameter is uni versally defined as the failure probability of the material due to the growth of the damaged regions. From the evolution equation of damaged regions and minimum strength principle, a partial differential equati on which universally describes the evolution of the damage parameter i s found. This equation can not only characterize the kinetic process o f damage evolution, but also establish the relationships between the m echanism of damage-growth of the microscopically damaged regions and t he result of damage-degradation of material properties.