An alternative approach to that described in the preceding subsection is to determine a potential service life based on a model of the capillary degree of saturation as a function of the suction time (Fagerlund, 1993). The service life is also a function of the wetness of the environment. The capillary water uptake and long-term water absorption of the air pore system are the significant issues and are modelled by a time relationship.
The potential service life (tp) is defined by the critical level of saturation (SCR) which itself is related to the capillary degree of saturation (SCAP). Thus:
These relationships could be used to examine the potential service life in particular situations and form the basis for robust models to be used in durability design and performance-based specifications. In time, other variables could be added to take account of interactions. Later, statistical data could be used to refine the models and contribute to our understanding of the implications of this durability phenomenon in a period of global climate change.
