Mortars containing cement with silica fume (sf) replacements of 0, 10, 20 and 30% were produced. Following 28 days of curing in water at 20 degrees C +/- 2 degrees C, the mortars were kept in water, Na,SO, solution of pH = 6 and in laboratory atmosphere at 20 +/- 2 degrees C and 65 +/- 5% R.H. The specimens kept in water and sulfate solution were tested for absorption and unit mass, and those stored in air were tested for shrinkage. The coefficient of capillary absorption of 0%, sf mortar exposed to sulfate increased up to 3.07 times that of the mortar cured in water while the value for the 30% sf mortar was 0.48; indicating a reduction when exposed to sulfate. The water absorption decreased by 12% at sf replacement of 30%. Shrinkages of the 20% and 30% sf were close to each other and were about 1.5 times that of the 0% and 10% sf, starting with the age of 7 days. (C) 1997 Elsevier Science Ltd.