The process of laying National Highway underwent a paradigm shift last week with the use of waste plastic for re-laying a stretch near Vickravandi in Villupuram district.
A four-lane stretch of about a km of the NH towards Chennai was re-laid by the Ulundurpet Expressways using a technology developed by the Centre for Studies on Solid Waste Management of the Thiagarajar College of Engineering (TCE) here. The process involved double saving as the existing road was reclaimed for re-laying. Sixty five per cent of the reclaimed materials and 35 per cent of new aggregate coated with waste plastic formed the re-laid stretch.
R. Vasudevan, Dean, TCE, said that the decision to apply the technology for using waste plastic for road laying was taken for the NH after rigorous tests of load-carrying capacity of reclaimed materials when used with plastic-coated aggregate.
“The road strength has gone up and there has been a considerable saving of cost. It has also meant 65 per cent saving of stones quarried from hills and a similar saving on bitumen. The other advantage is that the road level does not rise as no additional layer is constructed over the existing one,” said Dr. Vasudevan.
The Union Ministry of Road Transport and Highways, in its circular of November 9, 2015, has stipulated that “bituminous mix with waste plastic shall be the default mode for periodic renewal with hot mixes within 50 km periphery of urban area having population of more than five lakhs.”
Past experience of road laying with waste plastic has shown that maintenance cost is very low and life of the road gets increased as the plastic-coated aggregate is capable of withstanding wear and tear in summer and rains.
Plastic waste from a paper mill in Virudhunagar district was used for re-laying the road near Vickravandi.
It has been planned to use waste plastic for another 15 km.
Commending the effort, I. K. Pateriya, Director (Technical), National Rural Roads Development Agency, has said in a communication to TCE that the process of recycling, which is common in developed countries, is just picking up in India. However, use of aggregated coated with waste plastic along with recycled material is a “new idea.”