Asphalt

DEFINITION OF ASPHALT

ASPHALT

- is a sticky, black and highly viscous liquid or semi-solid that is present in most crude petroleums and in some natural deposits, notably around certain bodies of water and in oil sands. Until the 20th century, the term asphaltum was also used. It is most commonly modelled as a colloid, with asphaltenes as the dispersed phase and maltenes as the continuous phase. It consists almost exclusively of bitumen, a substance composed of polycyclic aromatic hydrocarbons (PAHs).

- is a material made from dried crushed rock and petroleum compounds. It's a natural and 100-percent recyclable material that is useful in a vast range of applications, from paving roadways and basketball courts to lining reservoirs and fish hatcheries.

- the term asphalt is often used as an abbreviation of asphalt concrete. Asphalt concrete is a composite material commonly used in construction projects such as road surfaces, airports and parking lots. It consists of asphalt (used as a binder) and mineral aggregate mixed together, then laid down in layers and compacted.. It is also increasingly used as the core for embankment dams. The terms "asphalt (or asphaltic) concrete", "bituminous asphalt concrete" and the abbreviation "AC" are typically used only in engineering and construction documents and literature. Asphalt concrete pavements are often called just "asphalt" by laypersons who tend to associate the term concrete with Portland cement concrete only.

- the word asphalt is derived from the late Middle English : from French asphalte, based on Late Latin asphalton, asphaltum, which is the latinisation of the Greek ásphaltos/ásphalton, a word meaning "asphalt/bitumen/pitch".

- another description has it that the term derives from the Accadian term asphaltu or sphallo, meaning "to split." It was later adopted from the Homeric Greeks as a verb meaning "to make firm or stable," "to secure.

- asphalt is called a bituminous material because it contains bitumen, a hydrocarbon material soluble in carbon disulfate. The tar obtained from the destructive distillation of soft coal also contains bitumen. Both petroleum asphalt and coal tar are referred to as bituminous materials. Because their properties differ greatly, petroleum asphalt should not be confused with coal tar. petroleum asphalt I composed entirely of bitumen while the bitumen content in coal tar is relatively low. The two materials should not be treated as separate entities.

- in American English, asphalt (or asphalt cement) is the carefully refined residue from the distillation process of selected crude oils. Outside the U.S., the product is often called bitumen. Natural deposits terminology also sometimes uses the word bitumen, such as at the La Brea Tar Pits. The primary use