Civil Engineering Today

  Bituminous Materials Bituminous materials are dark brown or black, semi-solid or liquid, thermoplastic mixtures of hydrocarbons derived from natural or synthetic processes in which hydrocarbon mixtures have lost their volatile components leaving a denser residue. The different types of Bituminous Materials are: 1.     Asphalt 2.     Bitumen 3.     Tar   1. Asphalt - The asphalt is a mechanical mixture of inert mineral matter like alumina, lime, silica, etc. and the asphaltic bitumen. It is black or brownish black in colour. It remains in solid state at low temperature and becomes liquid at a temperature of about 50°C to 100°C.   CLASSIFICATION OF ASPHALT - The asphalt is classified into the following tee categories: 1. Natural asphalt 2. Residual asphalt.   1. Natural asphalt - This variety of asphalt is obtained from nature. It is further subdivided into two groups, namely, lake asphalt a...