Question

In all-purpose Specification for Civil Engineering Works, it details temperature requirements for bituminous material all through and after mixing. What is cause behind this?

Answer

Temperature is one of factors that govern compaction of bituminous material and air void content is found to reduce with increase in compaction temperature. This fact is explained by viscosity-temperature relations- higher is the viscosity of binders, greater is resistance to compaction. Thus, in normal contract for bituminous laying, temperature requirements for bituminous material all through and after addition are specified.