Continuum Damage of Cement Paste and Mortar as Affected by Porosity and Sand Concentration

Continuum damage models are presented within the framework of elastic‐damage theory for cement paste and mortar. Basic elements of continuum damage mechanics are given, and various types of extensions of elastic‐damage models are proposed. The limitations and possible extensions of these models when applied to concrete are also presented. To facilitate model implementation, a simple and efficient computational update procedure for damage variable is also considered. To assess the applicability of the damage models proposed, well‐documented experimental programs are performed through the use of a data acquisition system developed in the University of California, Berkeley. In particular, through the use of a systematic parameter estimation algorithm, the effects of porosity and sand concentration on the initiation and growth of microcracks are clearly demonstrated.