Asphalt Exam Questions and Answers Best rated A+ Guaranteed Success Latest Update

How are Natural Asphalts formed? - When crude petroleum oils rose to the earths surface and formed pools, The action of the sun and wind drove off the lighter oils and gases, leaving a heavy residue. What are the differences in asphalt and tar? - Asphalt- a dark brown black cementitious material, solid or semisolid in consistency, in which the predominating constituents are bitumens which occur in nature such as or are obtained as residue in refining petroleum. Tar-brown or black bituminous material, liquid or semisolid in consistency, in which the predominating constituents are bitumens obtained by condensates in the destructive distillation of coal, petroleum, oil, shale, wood, or other organic materials, and which yields substantial quantities of pitch when distilled. What are bituminous materials? - Mixture of hydrocarbons of natural or pyrogenous origin or combinations of both, frequently accompanied by their nonmetallic derivatives, which are completely soluble in carbon disulfide. What are the classifications of petroleum crude oil, based on their asphalt content? - 1) Asphaltic base crude (almost entirely asphalt) 2) Paraffin base crude (contains paraffin but no asphalt) 3) Mixed base crude (contains both paraffin and asphalt) 5) How is the percentage of asphalt in a crude oil determined? - Amount of asphalt obtained from a crude oil is based on its API gravity. The higher the gravity the lower asphalt and vise versa 6) What distillation process is used to produce asphalt? - Typical crude oil is produced through a distillation tower. The crude oil is heated to 650 degrees to 700 degrees and fed into the atmospheric tower. Materials will rise based on their boiling points and the residual, heavy material is the asphalt binder.7) What do the basic tests of asphalt materials measure? - The consistency properties of catonic and anionic emulsions using a viscosity test at two different temps. The relative properties of asphalt emulsions and the cement residue, and many others 8) Basic requirements of asphalt pavement? - 1) Have sufficient total thickness and internal strength to carry expected traffic loads 2) Prevent penetration or internal accumulation of water 3) Have a top surface that is smooth and resistant to wear distortion, skidding, and deterioration by weathering and deicing chemicals. 9) Factors to consider when designing asphalt pavement thickness? - 1) Traffic to be served initially and over the design service of the pavement. 2) Strength and other pertinent properties of the subgrade 3) Strength and other influencing. Characteristics of the materials are available or chosen for the layers or courses in the total asphalt pavement structure. 4) Any special factors peculiar to the road being designed 1) Traffic to be served initially and over the design service of the pavement. 2) Strength and other pertinent properties of the subgrade 3) Strength and other influencing. Characteristics of the materials are available or chosen for the layers or courses in the total asphalt pavement structure. 4) Any special factors peculiar to the road being designed