Assessing the efficiency of entrained air voids for freeze-thaw durability through modeling

This paper models concrete's resistance to cyclic freeze/thaw using the solution of the poromechanical problem, which describes the freezing of an individual air void surrounded by hydrated cement paste. This enables calculation of the pore pressures and the volume of water expelled into the air void upon freezing. The model was applied to concrete specimens with entrained air voids with polydispersity in size, and subjected to water absorption, thereby simulating a cyclic freeze/thaw laboratory test. The mean and maximum pore pressures obtained by the simulation were compared to a series of experimental tests per ASTM C666, and results suggest the model may be used to predict satisfactory durability in the laboratory test. This framework may be useful tool to study the effects of porespace and entrained air void size distribution on concrete's freeze/thaw durability. Furthermore, it allows for a theoretical basis for assessing the entrained air void system parameters.