ABSTRACT
Concrete is a strongly heterogeneous, discontinuous and porous material. Under non-isothermal conditions, the movement of fluid in the pore and capillary system is strongly coupled with heat transfer. In such conditions, the pores and cracks facilitate the penetration of external aggressive agents into concrete that degrades both concrete and reinforcement. An innovative DEM-based thermo-hydro-mechanical model was developed to track in detail the liquid/gas fractions in pores and cracks with respect to their different geometry, size, location and temperature. A coarse 2D mesh was generated to create a fluid flow network and to solve the energy conservation equation. The thermo-hydro-mechanical model was verified by comparing the results with the analytical solution to the problem of one-dimensional heat transfer in a solid. Finally, the relevance of a fully coupled thermo-hydro-mechanical model is illustrated by the simulation of an experiment in which a saturated porous specimen is subjected to a cooling process.
