A theoretical model predicting the freezing behavior of porous materials such as concrete is presented. The model is derived from thermodynamic equilibrium condition and fracture mechanics considerations. Fundamental equations were drived on the microscopic level and then the resulted local deformation around pores was averaged to evaluate the nominal strain on a macroscopic level. In the model on the microscopic level, temperature-induced phase transitions and the resulting mass-transfer within the pore structure of the materials were taken into consideration. Components of the macroscopic deformation in the presented model are the expansion due to the internal pressure caused by the phase transition and the shrinkage due to the mass-transfer caused by the ice-lense mechanism. Experimental studies were carried out with mortar specimens of three different mix proportions. Then the theoretical prediction was compared with the experimental results and a good agreement was obtained.
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