Page 56 - Design of Reinforced Masonry Structures

MASONRY UNITS: APPLICATIONS, TYPES, SIZES, AND CLASSIFICATION 2.9

TABLE 2.1 ASTM Brick Classification [2.10]

Types of brick units ASTM designation*
Building brick (solid) ASTM C62 [2.12]
Facing brick (solid) ASTM C216 [2.14]
Hollow brick ASTM C652 [2.15]
Paving brick ASTM C902 [2.16]
Ceramic glazed brick ASTM C126 [2.17]
Thin brick veneer units ASTM C1088 [2.18]
Sewer and manhole brick ASTM C32 [2.19]
Chemical resistant brick ASTM C279 [2.20]
Industrial floor brick ASTM C410 [2.21]
Load-bearing wall tile ASTM C34 [2.22]
Nonload-bearing wall tile ASTM C56 [2.23]
*
American Society for Testing and Materials, West Conshohocken, PA.

repeated here. There are several terms in each standard used for classification, which may
include exposure, appearance, physical properties, efflorescence, dimensional tolerances,
distortion, chippage, cores, and frogs. Classification of bricks is determined by the usage
of brick in specific applications. Bricks are classified in most specifications by use, type,
and/or class. All options should be specified as each ASTM brick standard has requirements
for grade and type that apply automatically if an option is omitted. By not specifying the
desired requirements, a delivery may contain bricks not suitable for the intended use. Bricks
used in the wrong application can lead to failure or an unpleasing appearance [2.10].

2.4.4 Brick Sizes and Nomenclature

A size characteristic of brick units is their smallness. Brick is a building element with a
human scale. Although brick sizes have varied over the centuries, essentially they have
always been similar to the present-day sizes. The size of a brick has historically been small
enough to be held in the hand, and most bricks have remained small. A discussion on brick
sizes and related information can be found in Ref. [2.11].
Advances in brick construction and needs for specific designs led to the development
of new brick sizes. These include hollow units for reinforced construction, and larger units
for faster construction and increased economy. Hollow units have varying coring patterns
but are typically larger than standard or modular size, and have larger cells to allow place-
ment of vertical reinforcement. Obviously, the brick size has influence on completion time
required for a job. For example, units with larger face dimensions allow a brick layer to

lay more square foot of wall per day. Such units, compared to standard or modular size
units, may increase the number of bricks laid per day by as much as 50 percent. However,
as units get larger, they also become heavier, require more effort in lifting and placement,
and reduce productivity [2.11].
Interestingly, efforts have been made in the past to develop brick laying machines
in order to increase productivity in brick masonry construction. According to literature
[2.24–2.28], the bricklaying machines have been around since 1902 when Knight, an
Englishman, invented a model with which “any one could lay 500 to 600 bricks per hour”
[2.24]. Over the years, several efforts were made in different parts of the United States,
with claims ranging from laying 1200 bricks per hour to 10,000 bricks in 8 hours, but
none proved to be commercially successful. A discussion on mason productivity has been
provided by Grimm [2.28].