Engineering Mechanics

Proceedings Vol. 15 (2009)

ENGINEERING MECHANICS 2009

Copyright © 2009 Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, v.v.i., Prague

 

M. Horák, M. Jirásek
pages 425 - 433, full text

Continuum damage mechanics provides an appropriate modeling framework for materials weakened by evolving defects. However, local damage models fail to provide an objective description of the material behavior after the loss of ellipticity, which can be detected by classical methods of localization analysis based on the acoustic tensor. This paper presents analysis of localization properties of the family of isotropic damage models with one scalar damage variable driven by the equivalent strain, and also of a more sophisticated model proposed by Comi and Perego (2001) and designed specifically for concrete. Necessary conditions for the formation of a weak discontinuity (jump in strain) are derived and the dependence of the orientation of potential discontinuity surface and of the critical tangent modulus on the stress state is discussed. The results are confirmed by finite element simulations. ´

Text and facts may be copied and used freely, but credit should be given to these Proceedings.

All papers were reviewed by members of the scientific committee.