Concrete masonry units provide strength, durability, fire resistance, energy efficiency and sound attenuation to a wall system. Masonry is an inhomogeneous material, composed of units and mortars, which can be of different types, with different mechanical properties. The design of the masonry and mortar units is based on the role of the walls in the building. Load-bearing walls refer to structural elements that mainly support vertical loads, but which can also serve to withstand horizontal loads.
When a structural masonry building is subject to loads inside and outside the plane induced by an earthquake, for example, masonry walls are the structural elements that guarantee the overall stability of the building. This means that walls must have adequate mechanical properties that allow them to withstand different combinations of compressive, shear and tensile stresses. Boundary conditions influence the resistance mechanisms of structural walls subject to loads on the plane and, in a building, the connection in the intersecting walls is of paramount importance. Masonry mortar is composed of one or more cementitious materials, clean, well-graded masonry sand, and sufficient water to produce a plastic, viable mixture.
Masonry grout is made of similar materials, but is generally mixed to obtain a much more fluid state. May also contain coarse-grained aggregates.