Bulking of sand refers to the increase in the volume of fine aggregates, particularly sand, due to the presence of moisture. When water is added to dry sand, a thin film forms around each sand particle, causing them to repel each other and resulting in an increase in the overall volume of the sand. This phenomenon is most pronounced in fine sands and diminishes as the particle size in... https://www.123articleonline.com/articles/1495484/bulking-of-sand-implications-for-mortar-and-plaster-work