Drying shrinkage, creep and cracking of concrete: from coupled material modelling to multifield structural analyses

The paper describes a 3D coupled thermo-hygro-mechanical model that is formulated within the framework of thermomechanics of partially saturated porous media in the sense of the BIOT-COUSSY -theory. According to the coupled state equations arising from this theory, moisture transport and the constitutive pre- and postcracking properties are coupled by means of macroscopic coefficients. They are determined on the one hand by relating microscopic and macroscopic quantities and on the other hand by exploiting the symmetry relations that are connected to the existence of a macroscopic potential, yielding a model that is based on a minimum of material parameters. In addition to shrinkage-induced deformations also creep is considered in this extended version of the model. As a representative example, a numerical simulation concerning the long-term degradation of an inner tunnel lining is described in the paper.