Influences of Calcium Stearate on Compressive Strength and Water Absorptionof Hydrophobic Mortar

This article presents influence of calcium stearate (CS) which is the water-repellent admixture on compressive strength, water absorption, and surface contact angle of mortar. The CS contents used in mortar are varied in range of 0-15 percent by weight of binder. The obtained results indicated that the increasing of CS content resulted in the decreasing of compressive strength of mortar. The compressive strength at 28 days of mortar with CS at 5 and 15 percent by weight are reduced approximately 11 and 30 percent as compared with the control mortar (CT-CS0). While that of the water absorption of mortar mixed with CS at 9 percent (CT-CS9) is reduced about 90 percent as compared with CT-CS0. Moreover, surface contact angle of CT-CS9 is also more than 90 degrees which is classified as the hydrophobic characteristic.