CE 262 test 3 with Complete Solutions

CE 262 test 3 with Complete Solutions Describe the differences between asphalt cement, asphalt cutbacks, and asphalt emulsions, and explain why asphalt emulsions are preferable to asphalt cutbacks. - ANS ️️ Asphalt cement is a blend of hydrocarbons of different molecular- weights, heavier molecular weight hydrocarbons result in harder and more viscous asphalt. Asphalt cement is semisolid at room temperature, heated before applying, and has excellent adhesive characteristics and is the most common binder material used in pavements. Asphalt cutbacks are produced by dissolving asphalt cement in a lighter molecular weight hydrocarbon solvent. They are applied easily in the field without heating but expensive, hazardous, and bad for the environments. Asphalt emulsions are produced by dispersing asphalt in water and using an emulsifying agent. Asphalt emulsions are preferred because they are not hazardous and not as costly. The figure below shows the viscosity vs. temperature relationship of two asphalt binders. Both have the same viscosity at temperature T1. Which asphalt (A or B) would be proffered for use in a location with a wide variation in temperature throughout the year and why? - ANS ️️ Asphalt A because its viscosity is more stable with changing temperatures