ABSTRACT
The Composite Dilatancy Model (CDM) describes transient and steady-state creep, the evolution of dilatancy and damage, failure, and the post-failure behavior of different types of rock salt under different loading conditions and temperatures. Creep is modeled by constitutive equations for the velocity of mobile dislocations and their interactions with other dislocations, particles of salt minerals and with the changing subgrain microstructure of the material. Above the dilatancy boundary the CDM takes into account the increasing influences of damage and humidity on deformation which result in a higher deformation rate and inelastic volumetric strains. After failure, the CDM describes the considerable reduction of the load-bearing capacity of rock salt and its approach to a residual strength which corresponds to a stress level near the dilatancy boundary. In this contribution the current stage of development of the CDM, its various features, and an example for its application are presented.
