Mortar: a binding substance used in bricklaying on construction, consisting of a certain proportion of sand and cementing materials (cement, lime paste, clay, etc.) with water and into, also called mortar, also as mortar. Mortar is made of cementitious materials (cement, lime, clay, etc.) and fine aggregate (sand) mixed with water. Commonly used are cement mortar, mixed mortar (or called cement-lime mortar), lime mortar and clay mortar.

Classification of construction mortar by the cementitious materials, fine aggregate and water in a certain proportion.

According to the composition of the material, building mortar can be divided into:

①Lime mortar. Made of lime paste, sand and water according to a certain ratio, generally used for masonry and plaster layer with low strength requirements, not subject to moisture;

② cement mortar. Made of cement, sand and water at a certain ratio, generally used in damp environments or water masonry, walls or floors, etc.;

3 mixed mortar. In the cement or lime mortar mixed with appropriate admixtures such as fly ash, diatomaceous earth, etc., to save cement or lime dosage, and improve the compatibility of mortar.

Second, according to its use can be divided into:

①masonry mortar; ② plastering mortar

Compressive strength

Fresh ordinary mortar should have good compatibility, hardened mortar should have the required strength and bonding. The ease of mortar and its fluidity and water retention, generally according to the construction experience or through the test to determine. The compressive strength of mortar with mortar labeling, commonly used ordinary mortar labeling 4, 10, 25, 50, 100 and so on. For high strength requirements and important masonry, only need to use more than 100 mortar. The bonding force of mortar is enhanced with the increase of its standard, and also with the surface condition of masonry, clean or not, the degree of moisture and construction and maintenance conditions. Therefore, brick laying before the general need to first pour the brick wet, in order to enhance the bond between the brick and mortar, to ensure the quality of masonry.