Cement mortar, Mortar made up of cement, fine aggregate and water, and lime, active admixture or admixture added as needed, is divided into cement mortar and cement mixing mortar. Generally referred to as 1:3 cement mortar is used with 1 unit of cement and 3 units of weight sand, actually ignore the composition of water, generally in the ratio of about 0.6, that is, should be 1:3:0.6, the density of cement mortar is 2000Kg/m3.