Hydration occurs when Portland cement in the concrete and mortar reacts with water. This reaction binds the aggregates into solid concrete masonry units and helps the mortar develop the bond needed between adjacent units. Because the cement reaction supports both unit formation and joint bonding, hydration is central to achieving a durable masonry assembly with effective compressive-force transfer.
Mortar does more than hold concrete masonry units together. It bonds neighboring units and transfers compressive forces across the joints, allowing the wall or structural element to act as an assembly rather than as separate blocks. Joint design therefore becomes an engineering consideration because it affects how forces move through the masonry system.
Engineers select unit geometry, strength, density, joint design, and, when needed, grout or reinforcement according to structural and environmental requirements. Geometry affects the configuration of the assembly, while strength and density help match the units to project demands. Joint details and added reinforcement or grout provide further control over how the system meets those requirements.
The design process begins by identifying the structural and environmental requirements, then selecting compatible unit geometry, strength, density, and joint design. Engineers also determine whether grout or reinforcement is needed. This coordinated selection produces a masonry system suited to its intended role, such as a load-bearing wall, foundation, retaining structure, partition, or exterior façade.
Concrete masonry serves several construction roles, including load-bearing walls, foundations, retaining structures, partitions, and exterior façades. The appropriate application depends on the required structural function and environmental demands. Its broad use reflects the ability to configure the system for both structural elements and non-load-bearing or enclosure-related construction needs.
Concrete masonry is selected when projects require an efficient system with durability and fire resistance. Its performance derives from cement-based concrete masonry units, bonded mortar joints, and, where appropriate, grout or reinforcement. These characteristics support applications ranging from foundations and retaining structures to exterior façades, while the design variables allow engineers to address different structural and environmental requirements.