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Bitumen and bituminous materials have been known and used in construction works since
ancient times, approximately 6000 B.C. Asphalts were used as cements to hold stonework
together in boat building and as waterproofing in pools and baths. Some asphalt was mixed
with stand and used to pave streets and palace floors. The Egyptians made use of asphalt in
the mummification process and as a building material. The Greeks and Romans not only used
asphalt as a building material but also used burning asphalt as a military weapon. The asphalt
used by these ancient civilizations was natural asphalt formed when crude petroleum oils rose
to the earth’s surface and formed pools. The action of the sun and wind drove off the lighter
oils and gases, leaving a heavy residue. The residue was asphalt with impurities such as water
and soil present. Using crude distillation process, cementing and waterproofing materials
were obtained.
The word bitumen comes from the original sanskrit word Gwitumen applied to native
asphalts as fuel. Bitumens are mainly composed of a mixture of high-molecular hydrocarbons,
methane, napthane and other aromatic series and their oxygen or sulphur derivatives. Tar and
asphalt are the two varieties of bituminous materials. Tars are bituminous condensates
obtained in the process of destructive distillation of coal, petroleum, wood and other organic
materials at high temperature without access of air. They are composed of hydrocarbons and
their sulphurous, nitrous and oxygen derivatives. Asphalt on the other hand is a naturally
occurring bitumen which is a combination of an inorganic mineral matter either calcareous or
siliceous and an organic matter—a chemical compound of carbon and hydrogen.
Bitumens and bituminous materials are being extensively used in damp proofing the
basements, floors, roofs, damp proof courses; painting timber and steel structural elements;
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