60% RAP Technology Demonstration on NH-716 Highway

The 60% RAP Technology trial on National Highway-716 marks an important step towards greener road construction in India. CSIR-Central Road Research Institute (CSIR-CRRI), Structural Engineers Private Limited (OSEPL) and Ooms India carried out the trial on the Chennai–Tirupati Package-I section.

60% RAP Technology on NH-716

The trial used 60% Reclaimed Asphalt Pavement (RAP) in the Dense Bituminous Macadam (DBM) layer. RAP comes from old road surfaces. It contains useful stone and aged bitumen. Therefore, engineers can process and reuse these materials in new road work.

The team demonstrated the full recycling process. First, workers recovered and processed the RAP. Next, experts checked its material quality and studied the aged bitumen. They then used a suitable mix design and rejuvenation process. Finally, the team produced the mix at a hot-mix plant, laid it on the highway and compacted it.

Moreover, the trial shows how old road material can become a useful resource. As a result, greater RAP use can reduce the need for new aggregates and bitumen. It can also help reduce construction waste and save natural resources.

REJUBIT: Key Technology

Another important part of the trial was REJUBIT. CSIR-CRRI and Ooms India jointly developed this indigenous RAP rejuvenator. It helps restore important properties of aged bitumen in reclaimed asphalt.

Consequently, REJUBIT can support the use of higher amounts of RAP in new asphalt mixes. The NH-716 trial also marks the move of this Indian technology from laboratory work to field use.