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Masonry began spontaneously in the creation of low walls from stone or pieces of
caked mud from dried puddles. Mortar was originally mud smeared into the rising
wall to lend stability and weather tight seal. Where stone lay readily at hand,
it was preferred to bricks; where stone was unavailable, bricks were made from
local clay and silts. Change came with the passing millenia. People learned to
quarry, cut and hand chisel stone with increasing precision. Fires built
against mud brick walls brought knowledge of the advantages of burned brick,
leading the invention of the brick kiln. Masons learned the art of turning
limestone into lime, and lime mortar gradually replaced mud. By the fourth
millenium BC, the peoples of Mesopotamia were building palaces and temples of
stone and sun-dried brick.
In the third millennium, the Egyptians erected the first of their stone temples
and pyramids. In the last centuries before the birth of Christ, the Greeks
perfected their temples of limestone and marble. When control of Western
Civilization passed to Romans, they made the first large-scale use of masonry
arches and roof vaults in their basilicas, baths, palaces, anf aqueducts.
Medieval civilizations in both Europe and the Islamic world brought masonry
vaulting to a very high and sophisticated plane of development. The Islamic
craftsmen built magnificent palaces, markets and mosques of brick and often
incorporated glazed clay tiles. The Europeans focused their energies toward
fortresses and cathedrals of stone, culminating in the pointed vaults and
flying butresses of the great Gothic churches.
The civilizations of Central America, South America and Asia were carrying on
simultaneous evolution in cut stone. During the Industrial Revolution in Europe
and North America, machines were developed that quarried and worked stone,
molded bricks and aided in the transportation of these heavy materials to the
building site. Sophisticated mathematics were applied for the first time to the
analysis of masonry arches and the art of stonecutting. Portland cement mortar
came into widespread use, enabling the construction of masonry buildings of
greater strength and durability. In the late nineteenth century, masonry began
to loose its primacy among the materials of construction. The very tall
buildings of the central cities required frames of metal to replace the thick
masonry bearing walls that had limited the heights to which one could build.
Reinforced concrete, poured rapidly and economically into simple forms of wood,
began to replace brick and stone masonry in foundations and walls. The heavy
masonry vault was supplanted by lighter floor and roof structures of steel and
concrete. The nineteenth- century invention of the hollow masonry concrete unit
(CMU) helped revitalize masonry as a craft. The concrete block was much cheaper
than cut stone and required less labor to lay than brick. It could be combined
with brick or stone facings to make lower-cost walls that were still pleasing
in appearance. The brick cavity wall, an early nineteenth-century British
invention, also contributed to te revitalization of masonry. It produced a
warmer, more watertight wall that was later to adapt easily to the introduction
of thermal insulation when appropriate insulating materials became available in
the middle of the twentieth-century.
Over the twentieth-century, there have been many contributions to masonry
construction. These include the development of techniques for steel reinforced
masonry, high-strength mortars, masonry units (both bricks and concrete masonry
units) that are higher in structural strength and masonry units of many types
that reduce the amount of labor required for masonry construction. As we enter
the 21st century, masonry remains popular. Masonry is the choice of many
architects, developers and homeowners because of its beauty, durability and
endless possibilities.
A Fundamentals of Building Construction 2nd Edition
by Edward Allen
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