Block Sizes and Shapes:
Concrete block units are made in sizes and shapes to fit different
construction needs. Units are made in full and half length sizes,
Figure 7-37. - Typical sizes and shapes of concrete masonry
In figure 7-37,. Concrete unit sizes are usually referred to
by their nominal dimensions. A unit measuring 7 5/8 in. wide,
7 5/8 in. high, and 15 5/8 in. long is referred to as an 8x8x16
inch unit. When it is laid in a wall with 3/8 inch mortar joints,
the unit will occupy a space 16 inches long and 8 inches high.
Besides the basic 8x8x16 units, the illustration shows a smaller
partition unit and other units that are used as much as cut brick
or in brick masonry.
The corner unit is laid at a corner or at some similar point
where a smooth, rather than a recessed, end is required. The header
unit is used in a backing course placed behind a brick face tier
header course. Part of the block is cut away to admit the brick
headers. The uses of the other shapes shown are self-evident.
Besides the shapes shown in figure 7-37, a number of smaller shapes
for various special purposes are available. Units may be cut to
the desired shapes with a bolster or, more conveniently and accurately,
with a power-driven masonry saw.
The sides and the recessed ends of a concrete block are called
the SHELL (fig. 7-38).
Figure 7-38. - Concrete block:
The material that forms the partitions between the cores is called
the WEB, and the holes between the webs are called CORES. Each
of the long sides of a block is called a FACE SHELL, and each
of the recessed ends is called an END SHELL. The vertical ends
of the face shells, on either side of the end shells, are called