Page 59 - Design of Reinforced Masonry Structures

2.12 CHAPTER TWO

FIGURE 2.9 Nonmodular brick sizes. (Courtesy: BIA.)

of a new brick classification—the hollow brick, whose void area is greater than 25 percent
of its gross area. The development of hollow bricks began with 4 × 4 × 12 in. oversized
solid units followed by 6 × 4 × 12 and 8 × 8 × 16 in. hollow brick units. These large hollow
bricks are often called through-the-wall (TTW) units because the wall consists of a single
wythe of masonry. They offer a considerable advantage in both speed and economy of
construction. A discussion on hollow brick is presented in Ref. [2.29]. Configurations of
hollow bricks are shown in Fig. 2.5; their section properties are listed in Table 2.4.

TABLE 2.4 ASTM C652-01a Section Properties of Hollow Brick Units [2.15]
Minimum cored or Minimum end
Nominal width Minimum solid face double face shell shell or end web
†
*
of units, in. shell thickness, in. thickness , in. thickness , in.
3 and 4 3 ⁄ 4 – 3 ⁄ 4
6 1 1 1 ⁄ 2 1
8 1 1 ⁄ 4 1 1 ⁄ 2 1
10 1 3 ⁄ 8 1 5 ⁄ 8 1 1 ⁄ 8
12 1 1 ⁄ 2 2 1 1 ⁄ 8
* 2 2
Cores greater than 1 in. (650 mm ) in cored shells shall be not less than 1 ⁄ 2 in. (13 mm) from
2
2
any edge. Cores not greater than 1 in. (650 mm ) in shells cored not more than 35 percent shall be
not less than 3 ⁄ 8 in. (10 mm) from any edge.

†
The thickness of webs shall not be less than 1 ⁄ 2 in. (13 mm) between cells, 3 ⁄ 8 in. (10 mm)
between cells and cores or 1 ⁄ 4 in. (6 mm) between cores.
Hollow bricks are also made in a variety of special shapes to meet practical, architec-
tural, or aesthetic requirements. These special shapes include bullnose, radial, interior and
exterior angled units, and others.
2.4.5 Brick Dimensions
Bricks are identified by three dimensions: width, height, and length (Fig. 2.2). Height and
length are the face dimensions as seen when a brick is laid as a stretcher. When specifying