摘要：The growing cement demand is associated with high energy consumption and high release of carbon dioxide (CO2) emissions. Cement substitution by supplementary materials may tackle this problem, and herewith obtain the material with improved characteristics. The effect of partial replacement of cement by nanoclay on the properties of hardened cement pastes was investigated. The degradation of concrete is often caused by the penetration of water or other agents during operating conditions. The main durability related properties (sorptivity, compression strength and water absorption) of ordinary Portland cement (OPC) pastes as well as OPC with partial cement substitution by organically modified smectite (organoclay) from 0.5 up to 4% by weight of cement prepared at three water-to-solid ratios of 0.27, 0.31 and 0.36 were studied. Experimental results indicated a significant improvement in water penetration resistance of cement pastes with the addition of organoclay (OC). It was found a positive effect of cement replacement on the compressive strength characteristics of the materials as well. Test showed that optimum amount of organoclay is dependent on w/s ratio of the cement paste.
关键词：Durability; cement replacement; organoclay; sorptivity; water absorption; compressive strength
