Soil-water characteristic curve and permeability function of recycled concrete aggregates coated with oil or wax

Abstract

Recycled concrete aggregate (RCA) is known to be a hydrophilic material. An attempt has been made to convert RCA into a hydrophobic material by coating it separately with oil or wax. Both oil and wax are known to increase the hydrophobicity of soil. Although the soil-water characteristic curve (SWCC) and permeability function of coarse-grained aggregates have been investigated, the effect of the introduction of hydrophobicity (coating it with oil or wax) into the coarse aggregates to their SWCC and permeability function has not been fully understood. The SWCC indicates that coating RCA with oil or wax modifies the drying and wetting curves as compared with RCA without any coating. The air-entry values and water-entry values are also modified upon coating. RCAs coated with oil or wax were found to prevent ingress of water during the wetting test for SWCC. The permeability function of RCAs is also modified. © 2019 ASTM International.All Rights Reserved.