A concrete
block is primarily used as a building material in the construction of walls. It
is sometimes called a concrete masonry unit (CMU). A concrete block is one of
several precast concrete products used in construction. The term precast refers
to the fact that the blocks are formed and hardened before they are brought to
the job site. Most concrete blocks have one or more hollow cavities, and their
sides may be cast smooth or with a design. In use, concrete blocks are stacked
one at a time and held together with fresh concrete mortar to form the desired
length and height of the wall.
Concrete mortar was used by the Romans as early as 200 B.C. to bind shaped
stones together in the construction of buildings. During the reign of the Roman
emperor Caligula, in 37-41 A.D. , small blocks of precast concrete were used as
a construction material in the region around present-day Naples, Italy. Much of
the concrete technology developed by the Romans was lost after the fall of the
Roman Empire in the fifth century. It was not until 1824 that the English
stonemason Joseph Aspdin developed portland cement, which became one of the key
components of modern concrete.
The concrete commonly used to make concrete blocks is a mixture of powdered
portland cement, water, sand, and gravel. This produces a light gray block with
a fine surface texture and a high compressive strength. A typical concrete
block weighs 38-43 lb (17.2-19.5 kg). In general, the concrete mixture used for
blocks has a higher percentage of sand and a lower percentage of gravel and
water than the concrete mixtures used for general construction purposes. This
produces a very dry, stiff mixture that holds its shape when it is removed from
the block mold.
Concrete bricks is one of the modern bricks used for masonry work in the
developed countries and many developing countries as tested, qualified, specified,
conforming all of the specifications in U.S.A., Canada all European countries,
Japan, partly in China, partly in South East Asia, Australia, part of Africa,
the then USSR (CIS countries) and in all modern societies. The concrete bricks
materials having the following advantages:
- Low
cost, accuracy and uniformity of shape which makes lying and bonding easy.
- Smooth
surface and light color makes them suitable for internal walls without plaster i.e.;
factory units, sheds etc.
- Invariably
free from efflorescence.
- Unaffected
by repeated freezing or thawing.
- Resistance
to fire and the transfer of heat and sound is similar to that of clay bricks.
- Its
manufacture uses reusable energy and biogas.
- No
harmful residues or emissions are produced.
Considering above, Friends Corporation coupled a good number of professional and technical
expertise along with extensive industry knowledge to
provide the sustainable total solutions to establish a CC/CLC/AAC Block
industry with cost effective manner.