A thermodynamically consistent theory of gradient-regularized plasticity coupled to damage. (English) Zbl 0897.73023

Svedberg, T.; Runesson, K.

Int. J. Plast. 13, No. 6-7, 669-696 (1997).

Summary: A thermodynamically consistent theory of gradient-regularized plasticity with coupling to isotropic damage is presented. If the internal variables are gradient-enhanced, this leads to a nonconventional definition of the corresponding dissipative stresses (with a separate definition associated with external boundaries of the body). The main purpose is to use this theory for describing the successive development of the localization zone that is pertinent to the softening regime due to excessive damage close to failure. Localization characteristics of the linearized deformation field are assessed for the simple homogeneous tension bar as well as for the general stress state. In particular, it is predicted that the localization zone narrows with accumulation of damage. This prediction is indeed verified by a numerical solution in the case of uniaxial stress.

MSC:

74C99	Plastic materials, materials of stress-rate and internal-variable type
74A15	Thermodynamics in solid mechanics
74R99	Fracture and damage

Keywords:

internal variables; dissipative stresses; softening regime; homogeneous tension bar; localization zone