After researching the history of
clay brick, it has been told that the first brick probably was made in the
Middle East, between the Tigris and Euphrates rivers, in what is now Iraq. Early
builders here relied on the abundant natural materials to make their sun-baked
bricks. However, these were of limited use because they lacked durability and
couldn’t be used outdoors. Exposure to the elements caused them to
disintegrate. The Babylonians, who later dominated Mesopotamia, were the first
to fire bricks, from which many of their tower-temples were constructed.
From the Middle East the art of
brickmaking spread west to what is now Egypt and east to Persia and India.
Although the Greeks, having a plentiful supply of stone, did not use much
brick, evidence of brick kilns and structures remains throughout the Roman Empire.
However, with the decline and fall of Rome, brickmaking in Europe soon
diminished. It did not resume until the 1200s, when the Dutch made bricks that
they seem to have exported to England. In the Americas, people began to use
brick during the sixteenth century. It was the Dutch, however, who were
considered expert craftsmen.
Prior to the mid-1800s, people made
bricks in small batches, relying on relatively inefficient firing methods. One
of the most widely used was an open clamp, in which bricks were placed on a
fire beneath a layer of dirt and used bricks. As the fire died down over the
course of several weeks, the bricks fired. Such methods gradually became
obsolete after 1865, when the Hoffmann kiln
was invented in Germany. Better suited to the manufacture of large numbers of
bricks, this kiln contained a series of compartments through which stacked
bricks were transferred for pre-heating, burning, and cooling.
Brickmaking improvements have
continued into the twentieth century. Improvements include rendering brick shape
absolutely uniform, lessening weight, and speeding up the firing process. For
example, modern bricks are seldom solid. Some are pressed into shape, which
leaves a depression, on their top surface. Others are extruded with holes that
will later expedite the firing process by exposing a larger amount of surface
area to heat. Both techniques lessen weight without reducing strength.
However, while the production
process has definitely improved, the market for brick has not. Brick does have
the largest share of the opaque materials market for commercial building, and
it continues to be used as a siding material in the housing industry. However,
other siding materials such as wood, stucco, aluminum, plaster, and vinyl are
strong competitors because they cost up to 50 percent less, and some (notably
stucco and plaster) offer built-in insulation.
To produce brick, the raw materials
are first crushed and ground in a jaw crusher. Next, the ingredients are formed
using one of several methods. In extrusion, the pulverized ingredients are
mixed together with water, passed into a de-airing chamber (to prevent cracking),
compacted, and extruded out of a die of the desired shape.
The ancient Jetavanaramaya stupa in Anuradhapura, Sri Lanka is one of the largest brick structures in the world. |
The world's highest brick tower of St. Martin's Church is in Landshut, Germany, completed in 1500. |
The historic brick street lays in Natchitoches, Louisiana. |
The Roman Basilica Aula Palatina in Trier, Germany, was built with fired bricks in the 4th century, as an audience hall for Constantine I. |
Malbork Castle is the biggest brick castle in the world. |
The brickwork of Shebeli Tower in Iran displays 12th century craftsmanship. |
According to the U.S. Industrial
Outlook, the use of brick as a siding material for single-family homes dropped
from 26 percent in 1984 to 17 percent in 1989. Currently, the use of brick has
remained steady, at around seven to nine billion a year, down from the 15
billion used annually during the early 1900s. In an effort to increase demand,
the brick industry continues to explore alternative markets and to improve
quality and productivity. Fuel efficiency has also improved, and by the year
2025 brick manufacturers may even be firing their brick with solar energy.
However, such changes in technology will occur only if there is still a demand
for brick.
Even if this demand continues, the
brick industry both here and abroad faces another challenge: it will soon be
forced to comply with environmental regulations, especially in the area of
fluorine emissions. Fluorine, a byproduct of the brickmaking process, is a
highly reactive element that is dangerous to humans. Long-term exposure can
cause kidney and liver damage, digestive problems, and changes in teeth and
bones, and the Environmental Protection Agency (EPA) has consequently
established maximum exposure limits. To lessen the dangers posed by fluorine
emissions, brickworks can install scrubbers, but they are expensive. While some
plants have already installed such systems, the U.S. brick industry is trying
to play a more important role in developing less expensive emissions testing
methods and establishing emission limits. If the brick industry cannot persuade
federal regulators to lower their requirements, it is quite possible that the
industry could shrink in size, as some companies cannot afford to comply and
will go out of business.
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