Correct Answer - Option 4 : RT-4
Concepts:
There are 5 types of road tars, classified as RT-1, RT-2, RT-3, RT-4, RT-5, based on their viscosity and other properties.
RT-1 has the lowest viscosity and used for surface painting under exceptionally cold weather. The specific gravity of this road tar is 1.26.
RT-2 is recommended for standard surface painting under normal Indian climate condition. The specific gravity of this road tar is 1.26.
RT-3 is used for surface painting, renewal coats and premixed top course and light carpets. The specific gravity of this tar is 1.28.
RT-4 is generally used for premixing tar macadam in base course. The specific gravity of this tar is 1.28.
RT-5 has the highest viscosity and
used for grouting purpose. The specific gravity of this tar is 1.28
