THE EFFECT OF DIFFERENT DRYING TECHNIQUES ON THE PORE-SIZE DISTRIBUTION OF BLENDED CEMENT MORTARS

Porosity and pore size distribution measurements using mercury intrusion are reported for blended mortars (incorporating fly ash) dried by four different drying techniques. The drying techniques were: direct oven drying, solvent replacement drying, and two variations of freeze drying. Significant differences were observed in both porosity and pore size distribution results, depending on the technique used. It was concluded that the best technique with respect to preservation of pores is that using.solvent replacement. Both freeze drying techniques help preserve pores in the fine pore region (r < 5 nm) to some extent.