Empirical design of walls

Although most of the statements in this chapter apply to all structural walls constructed of all materials, including masonry, wood, steel, and concrete, our discussion will focus on masonry walls: in modern construction, walls built of concrete masonry units (CMUs).

An exterior masonry wall has two primary structural functions: to carry vertical loads from above and to resist lateral loads; lateral loads may consist of wind or earthquake loads applied perpendicular to the surface of the wall or loads in the plane of the wall. An interior masonry wall may be non-load-bearing, having to resist its own weight only, or load-bearing, carrying vertical loads from above. Shear forces, due to wind or earthquake loading, on the entire building have to be resisted by the walls parallel to the direction of the wind force, while walls perpendicular to the wind or earthquake force transmit their loads through the floor system to the shear walls (Figure 3.1). Structural walls, both load-bearing and shear walls, can also be built in other materials, including reinforced concrete, prestressed concrete, wood, and wood clad with other materials such as gypsum wallboard. The design of shear walls for resistance to wind or earthquake loading is described in Chapter 10. The discussions in this chapter concern gravity-loaded walls.