Brick is a type of masonry block used to construct walls, pavements, and other components. Brick is a word that refers to a block made of dried clay, although it is now frequently used to refer to various chemically cured building blocks. Mortar, glue, or interlocking can be used to bind bricks together. Bricks come in a variety of classifications, kinds, materials, and sizes that vary by area and period, and they are made in large quantities.
History
The Middle East and South Asia
Dried bricks were the first bricks, which were made from clay-bearing soil or mud and dried until they were strong enough to use. The oldest known bricks, built of molded mud and dating back to before 7500 BC, were unearthed in Tell Aswad in the upper Tigris area and near Diyarbakir in southeast Anatolia.
China
Around 4400 BC, the first burned bricks were discovered in Neolithic China at Chengtoushan, a walled city of the Daxi civilization. These bricks were constructed of red clay, burned to about 600°C on all sides, and utilized as home floors. Fired bricks were being utilized to pave roadways and as building foundations in Chengtoushan by the Qujialing era.
Europe
The usage of burned bricks was embraced by early civilizations around the Mediterranean, including the Ancient Greeks and Romans. The Roman legions erected enormous brick buildings and ran mobile kilns across the Roman Empire, stamping the bricks with the legionâs seal.
After being brought from Northern-Western Italy, the use of bricks in construction became widespread in Northern Europe throughout the Early Middle Ages. In areas where there were no natural rock sources, a distinct form of brick architecture known as brick Gothic emerged.
Until the advent of modern transportation infrastructures, such as canals, highways, and railroads, the long-distance bulk transport of bricks and other building equipment was prohibitively expensive.
Industrial era
With the start of the Industrial Revolution and the surge in factory construction in England, brick production skyrocketed. Bricks were increasingly chosen as a construction material over stone, especially in regions where a stone was freely accessible, for reasons of speed and cost.
Bright red brick was selected for construction in London at this period to make buildings more apparent in the thick fog and to help reduce traffic accidents. During the first part of the nineteenth century, the shift from the conventional technique of manufacturing known as hand-molding to a mechanized type of mass-production took place gradually.
Henry Clayton, who worked at the Atlas Works in Middlesex, England, invented the first effective brick-making machine in 1855, and it was capable of manufacturing up to 25,000 bricks per day with minimum monitoring.
After being accepted for use in brick-making at the South Eastern Railway Companyâs facility in Folkstone, his mechanical device quickly gained considerable notice. The âStiff-Plastic Brickmaking Machineâ patented by Bradley & Craven Ltd in 1853 appears to predate Clayton.
Bradley & Craven went on to become a major brickmaking machinery company. The brick-making machine invented by Richard A. VerValen of Haverstraw, New York, in 1852 predated both Clayton and Bradley & Craven Ltd.
The need for high-rise office buildings around the start of the twentieth century led to a larger usage of cast and wrought iron, as well as steel and concrete. The Monadnock Building, erected in 1896 in Chicago, required extremely thick walls to maintain the structural integrity of its 17 stories due to the usage of brick in skyscraper construction.
The use of enhanced masonry for the building of tall structures up to 18 stories high was made possible because of pioneering work in the 1950s at the Swiss Federal Institute of Technology and the Building Research Establishment in Watford, UK. However, brick has mainly been limited to small to medium-sized structures, while steel and concrete continue to be superior materials for high-rise construction.
Summary
Brick is a type of masonry block used to construct buildings. Dried bricks were the first bricks, which were made from clay-bearing soil. The first burned bricks were discovered in Neolithic China at Chengtoushan, around 4400 BC.
Methods of manufacturing brick
There are different methods of manufacturing bricks. These methods are given below:
Fired brick
The durability of fired bricks is because they are fired in a kiln. Soft mud, dry press, or extruded methods are used to make modern, burned clay bricks. Extruded or soft mud methods are the most prevalent, depending on the nation, because they are the most cost-effective.
Fired brick contains the following ingredients
| Ingredints | Percentage by weight |
|---|---|
| Silica | 50% to 60% |
| Alumina | 20% to30 % |
| Lime | 2% to 5% |
| Iron oxide | Less than 7 % |
| Magnesia | Less than 1 % |
Shaping method
The raw ingredients are shaped into bricks to be burned using three different methods:
Molded brick
The raw clay is used to make these bricks, which should be mixed with 25â30% sand to decrease shrinkage. First, the clay is crushed and combined with water until it reaches the appropriate consistency. A hydraulic press is then used to push the clay into steel molds. To produce strength, the molded clay is burnt (âburnedâ) at 900â1000 °C.
Dry-pressed bricks
The dry-press technique is similar to the soft-mud molded approach, except that it starts with a considerably thicker clay mix, resulting in more precise, sharper-edged bricks. This approach is more costly due to the increased power used in pressing and the longer burn time.
Extruded bricks
In a pugmill, the clay is combined with 10â15 percent water or 20â25 percent water for extruded bricks. The material is pushed through a die to form a long cable with the required width and depth. A wall of wires then cuts this material into bricks of the required length.
This technique is used to make the majority of structural bricks because it creates durable, thick bricks that can also be perforated with the right dies. The use of such holes decreases the amount of clay required, and therefore the cost.
Hollow bricks are lighter and simpler to handle than solid bricks, and they have distinct thermal characteristics. Before being burned, the cut bricks are toughened by drying for 20 to 40 hours at 50 to 150 °C. The heat used for drying is frequently kiln waste heat.
Kiln
Bricks are often burned in a continuously fired tunnel kiln in much contemporary brickworks, where the bricks are fired as they move slowly through the kiln on conveyors, tracks, or kiln cars, resulting in a more uniform brick output.
Lime, ash, and organic matter are frequently added to the bricks, speeding up the burning process. The Bullâs Trench Kiln (BTK), based on a design created by British engineer W. Bull in the late 1800s, is the other major kiln type.
A 6â9 meter broad, 2-2.5 meter deep, and 100â150 meter radius oval or circular trench is excavated. In the center, a towering exhaust chimney is built. Half or more of the trench is filled with unfired âgreenâ bricks piled in an open lattice design to enable ventilation.
The lattice is topped with a completed brick roofing layer. New green bricks, as well as roofing bricks, are placed at one end of the brick pile during operation. A âhackâ was a stack of unfired bricks that was covered for weather protection in the past.
The completed bricks are taken from the opposite end once they have cooled and are ready to be transported to their final destinations. The bricklayers construct a burning zone in the center by dumping fuel (coal, wood, oil, trash, and so on) via access holes in the trenchâs ceiling.
When compared to clamp or scove kilns, the BTK design has considerably higher energy efficiency. Fresh air is routed through the brick lattice using sheet metal or boards, heating the air as it passes through the previously burned bricks before passing through the current burning zone.
The air next passes through the green brick zone (which pre-heats and dries the bricks) before exiting the system through the chimney, where rising gases generate suction that pushes air through the system. The re-use of hot air saves money on gasoline.
As with the rail process, the BTK process is continuous. Approximately 15,000â25,000 bricks may be fired each day by a half-dozen laborers working around the clock. The bricks in the BTK process do not move like they do in the rail process. Rather, the sites where the bricks are loaded, burned and unloaded rotate through the trench gradually.
Influences on color
The chemical and mineral composition of the raw materials and the kiln environment all impact the color of burned clay bricks. Pink bricks, for example, have a high iron concentration, whereas white or yellow bricks have a greater lime content.
Most bricks burn to various red colors as the temperature rises; at about 1,300 °C (2,372 °F), the color transitions from dark red to purple, then to brown or grey. The names of bricks, such as London stock brick and Cambridgeshire White, may indicate their origin and color. Brick tinting is a technique for changing the color of bricks so that they mix in with the surrounding masonry.
Salt glazing, in which salt is applied during the burning process, or the use of a slip, which is a glaze substance into which the bricks are dipped, can be used to create an impermeable and decorative surface on brick. The slip is then reheated in the kiln to form a glazed surface that is integrated into the brick foundation.
Chemically set bricks
Chemically set bricks are not burned, although the curing process can be expedited in an autoclave by applying heat and pressure.
Calcium âsilicate bricks
Depending on the components, calcium-silicate bricks are sometimes known as sand-lime or flint lime bricks. Rather than using clay, they use lime to bond the silicate material together. Lime is combined in a proportion of 1 to 10 with sand, quartz, crushed flint, or crushed siliceous rock, as well as mineral colorants, to make calcium-silicate bricks.
Materials are combined and allowed to sit until the lime is completely hydrated; the mixture is then pressed into molds and cured in an autoclave for three to fourteen hours to speed up the chemical hardening process.
Although the jagged arrises need cautious handling to minimize harm to the brick and bricklayer, the final bricks are highly precise and consistent. The bricks may be produced in several colors, including white, black, buff, and grey blues, as well as pastel tints.
This style of brick is prevalent in buildings built or remodeled in the 1970s in Sweden, Belarus, Russia, and other post-Soviet nations. In South Asia, fly ash bricks, which are made from fly ash, lime, and gypsum, are popular.
Calcium-silicate bricks are also made in Canada and the United States, and they fulfill the ASTM C73 â 10 Standard Specification for Calcium Silicate Brick specifications.
Concrete bricks
Blocks or concrete masonry units are the most common names for concrete bricks, which are often pale grey. Theyâre constructed using dry, small-aggregate concrete thatâs poured into steel molds and compacted using an âegglayerâ or a static machine.
The completed blocks are cured, rather than burned, using low-pressure steam. Concrete bricks and blocks come in a variety of forms, sizes, and face treatments, some of which are designed to seem like clay bricks.
Concrete bricks come in a variety of colors and are produced using sulfate-resistant Portland cement or an equivalent. They are useful for tough settings such as damp climates and retaining walls when constructed with enough cement.
Theyâre produced to BS 6073, EN 771-3, or ASTM C55 specifications. Concrete bricks flex or shrink, necessitating movement joints every 5 to 6 meters, but in terms of thermal, acoustic, and fire resistance, they are comparable to other bricks of equal density.
Compressed earth blocks
The majority of compressed earth blocks are manufactured with a mechanical hydraulic press or a manual lever press from slightly moistened local soils. The use of a tiny quantity of cement binder can result in a stabilized compressed earth block.
Mudbrick
Unfired bricks, sometimes called mudbricks, are produced from moist clay-rich soil combined with straw or other binders. Theyâre left to air dry until theyâre ready to use.
Different types of methods are used for manufacturing bricks. These are mudbrick, fired bricks, compressed earth blocks, chemical-set bricks, etc.
Types of brick
There are different types of bricks based on size, use, manufacturing method, origin, etc. Some of these types are given below:
Types of brick based on the manufacturing method
Bricks are categorized based on the manufacturing method.
Extruded bricks
These bricks are created by forcing them through a hole in a steel die, and they have a highly uniform size and shape. Then trimmed to size with a tensioned wire after extrusion, which may create drag marks.
Molded bricks
Rather than being extruded, these bricks are formed in molds. This type has further two types:
Machine molded
Pressure is used to push the clay into molds in this method.
Handmade
A person forces clay into molds in this method.
Dry-pressed bricks
This technique of brick making is similar to the soft mud method, but it starts with a considerably thicker clay mix and is crushed with a lot of power.
Types of bricks based on use
Common or building brick
A common or building brick is a brick that is used for interior structure and is not meant to be seen.
Face brick
Face brick is a brick that is used to create a clean look on exterior surfaces.
Hollow brick
Hollow brick is not solid since the holes account for less than 25% of the total volume of the brick.
Perforated brick
A perforated brick has more than 25% of its volume taken up by holes.
Keyed brick
Itâs a brick having indentations on at least one face and end that are intended for use in rendering and plastering.
Paving brick
Paving brick is a brick that is designed to come in touch with the ground as a pathway or highway.
Thin brick
Itâs a veneer brick with a standard height and length but narrow width.
Special types of bricks
Chemically resistant bricks
These are bricks that can withstand chemical reactions.
Engineering bricks
Itâs a strong, thick brick thatâs utilized when you require strength, low water porosity, or acid (flue gas) resistance. Based on their compressive strength, they are further categorized as type A and type B. Accrington is a type of engineering brick made in the United Kingdom.
Fire or refectory bricks
These are bricks that can withstand a lot of heat.
There are different types of bricks such that face bricks, extruded bricks, handmade bricks, engineering bricks, fire bricks, hollowed bricks, perforated bricks, keyed bricks, etc.
Uses of bricks
Uses of bricks are given below:
United State
Bricks have been utilized for both structures and pavements in the United States. Brick is used in buildings all across the nation, including colonial-era structures and other significant constructions. Pavements made of bricks were popular in the late nineteenth and early twentieth centuries.
Although the introduction of asphalt and concrete limited the usage of brick pavements, they are still used as a traffic calming or aesthetic surface in pedestrian areas. For example, most of the streets of Grand Rapids, Michigan, were paved with bricks in the early 1900s.
Only around 20 blocks of brick-paved streets are still standing today. By the mid-twentieth century, towns across the United States, including Grand Rapids, had begun replacing brick streets with less costly asphalt pavement.
Metallurgy and glass industries
Refractory bricks such as silica, magnesia, chamotte, and neutral refractory bricks are often used for lining furnaces in the metallurgy and glass sectors. Thermal shock resistance, refractoriness under load, a high melting point, and adequate porosity are all requirements for this type of industry
Refractory bricks are widely used, particularly in the United Kingdom, Japan, the United States, Belgium, and the Netherlands.
Northwest Europe
Bricks have been used in building throughout Northwest Europe for millennia. Until recently, nearly every house was made almost completely of bricks. Many houses are still skinned with a layer of bricks on the outside for aesthetic appeal, even though many are now built with a mixture of concrete blocks.
Where strength, low water porosity, or acid resistance are required, engineering bricks are utilized.
United Kingdom
A red brick university is one that was created in the late 19th or early 20th century in the United Kingdom. The phrase is used to refer to such universities together to separate them from older Oxbridge colleges, and it alludes to their structuresâ use of bricks rather than stone.
Bricks have been used for constructing pavements in the United States. Bricks are used over all the world for constructing purposes.
Frequently asked questions (FAQs)
People usually ask many questions about âbrickâ, some of these questions are given below:
Is brick a rock?
Brick clay transforms into a metamorphic rock during the burning process. Clay minerals decompose, releasing chemically bonded water and transforming into a combination of quartz and mullite particles. During that period, the quartz crystallizes very little and remains in a glassy condition.
Why do some bricks become black?
In certain areas, more black marks on an outside brick wall can be seen. These are caused by rain splashing up onto the brick walls from the lower roof. Algal development on the brick surface has been promoted by the increased moisture content.
Why are some bricks red in color?
The chemical and mineral makeup of the clay, as well as the temperature at which it is burned, determine the color of bricks. Red bricks have a lot of iron in them, whereas yellow bricks have a lot of lime in them. Cooler temperatures result in red bricks, whereas hotter temperatures result in browns and greys.
What is the hardest brick?
For more than a century, the Nori brick company in Accrington has been producing the red, rock-hard Nori brick. According to legend, the firmâs name, which was formerly the Iron Brick Company, is iron spelled backward owing to a typo.
Who invented bricks?
The first bricks were laid here by English colonists, and while no official record exists, it is thought that they were laid for the first time in the early 17th century. Standard bricks were initially manufactured in Virginia around the 1610s, according to a few accounts.
Are Weinerberger bricks good?
They are breathable, sustainable, durable, and do not lose value over time. Wienerbergerâs Clay Blocks are environmentally friendly and sustainable. They can be found in family homes and flats, as well as in office buildings, hospitals, schools, and nurseries.
Why do some bricks become white?
Efflorescence is a salty crystallized coating that forms on the surfaces of bricks, concrete, and other building materials. Itâs white, either a bright white or off-white color. When salt-laden water reaches the brickâs surface, the water evaporates, leaving the salt behind.
Can you use engineering brick in place of face brick?
Engineering bricks are often utilized for their compressive strength and minimal water absorption rather than their aesthetic appeal. For a face brick or a brick veneer, a natural clay brick slip is a preferable option.
What are bricks mostly made of?
Bricks are primarily constructed of clay. Theyâre cooked in an oven after being pressed into molds or sliced with wires. The color of a brick is determined by the clay used to make it. Masons construct brick walls.
Which brick is best?
Ash bricks are superior to clay bricks in every way. They are environmentally good because the majority of the ingredient is ash, and fly ash bricks are stronger than red bricks. Fly ash brick, which is the best brick for home construction, is an option.
Brick is a type of masonry block used to construct buildings. Dried bricks were the first bricks, which were made from clay-bearing soil. Different methods of manufacturing bricks are mudbrick, fired bricks, compressed earth blocks, chemical-set bricks, etc.
Different types of bricks are bricks, extruded bricks, handmade bricks, engineering bricks, fire bricks, hollowed bricks, perforated bricks, keyed bricks, etc. Bricks are used over all the world for constructing purposes.