CSIR-CRRI, OSEPL and Ooms India Demonstrate 60% RAP Technology on NH-716
In a significant advancement for sustainable road construction in India, CSIR-Central Road Research Institute (CSIR-CRRI), Oriental Structural Engineers Private Limited (OSEPL) and Ooms Polymer Modified Bitumen Pvt. Ltd. (Ooms India) successfully demonstrated the use of 60% Reclaimed Asphalt Pavement (RAP) in the Dense Bituminous Macadam (DBM) layer on National Highway-716, Chennai–Tirupati Package-I. This field-scale demonstration, conducted on September 2, 2026, represents an important milestone in advancing high-RAP recycling technology under actual highway construction conditions.
The demonstration showcased the complete high-RAP recycling process, including RAP recovery and processing, material characterization, rejuvenation, mix design, hot-mix plant production, laying and field compaction. Participants including senior officials from the National Highways Authority of India (NHAI) and the Government of Tamil Nadu, along with representatives of highway infrastructure companies and technical experts, visited the Hot Mix Plant to understand the production process and an Experience Centre showcasing the journey of reclaimed asphalt from recovery to reuse.
A key component of the demonstration was REJUBIT, an indigenous RAP rejuvenator jointly developed by CSIR-CRRI and Ooms India. This technology is designed to restore key properties of aged bitumen present in reclaimed asphalt, facilitating the incorporation of a higher proportion of existing pavement material into new asphalt mixes. At 60% RAP utilization, a substantial proportion of the material required for the new asphalt mix is derived from the existing pavement, potentially conserving natural resources, reducing dependence on virgin and imported raw materials, minimizing construction waste and lowering the environmental footprint of highway construction.
Dr. Chalumuri Ravi Sekhar, Director of CSIR-CRRI, emphasized that RAP should not be viewed merely as waste but as an engineering resource containing valuable aggregate and bitumen that can be scientifically recovered, rejuvenated and reused. Dr. Ambika Behl, Senior Principal Scientist at CSIR-CRRI and Project Leader of the demonstration, described RAP as "black gold for the road sector" containing two valuable non-renewable resources already present within the existing road network.
The field trial was carried out through collaborative technical efforts involving OSEPL, CSIR-CRRI and Ooms India, combining highway construction expertise, scientific research and specialized rejuvenation technology. Mr. Nagaraj, Sr. CPM (Project Head) at OSEPL, noted that the 60% RAP trial provides an opportunity to evaluate high-RAP construction at field scale while maintaining required quality-control framework. Mr. Palash Kathal, Director of Ooms India, highlighted that taking a 60% RAP mix from laboratory evaluation through plant production to live highway laying represents a significant technical milestone.
Sh. Er. A. Venkatachalam, Director of Highway Research Station, Chennai, congratulated the participating organizations and described the demonstration as an important milestone for Tamil Nadu towards more sustainable and resource-efficient road construction. He observed that Tamil Nadu's extensive road network provides significant potential for recycling materials from existing pavements, which can reduce the demand for virgin aggregates and bitumen as well as construction waste.
The 60% RAP trial section on NH-716 was executed under the technical guidance of CSIR-CRRI, with Dr. Ambika Behl leading the project and Dr. Rajiv Kumar, Scientist E1 at CSIR-CRRI, actively involved in the design and construction along with teams from Ooms India and OSEPL. The initiative aims to generate technical and field experience on higher RAP utilization and contribute to the evidence base required for its responsible and wider adoption in Indian highway construction.