The water sorption phenomenon in a cementitious matrix is responsible for the ingress of
several deleterious agents, and it is directly related to pore connectivity and pore volume. One of the
most common tests used to describe this mechanism is the capillary sorption test. Furthermore, the
drying rate (DR) is a process that strongly depends on the transport properties and also provides
valuable information related to porosity and durability.
Supplementary cementitious materials (SCMs) are known to enhance durability-related properties,
especially pore refinement with time due to the pozzolanic action. Therefore, changes in the pore
structure could be assessed by means of the capillary sorption and drying rate.
For this study, mortars with ground granulated blast-furnace slag, natural pozzolan and limestone
powder at three different levels of replacement were made and the capillary sorption test was
performed at 28 and 90 days. Weight loss was also assessed at 28 days and the DR was calculated.
Calculation of the weight gain, weight loss, DR and capillary sorption rate (CSR) is made
considering the stoppage of the test at different stages. A comparison between different approaches
in the calculations is made. Also, the relation of DR and CSR is assessed. Results show the effect of
SCMs with time, and also the influence of the calculations on the CSR and DR values
