The idea of using plastic as a component in road laying is not a new one. In 2018, the government conferred R. Vasudevan, dean, Thiagarajar College of Engineering, with the Padmashri award for his groundbreaking research that prevents roads from developing cracks and potholes.
Traditional roads contain a mixture of gravel mixed at specific temperatures. “Here bitumen acts as a binder but when water stagnates, it can seep between the mixture and bitumen will peel off resulting in potholes”, he says.
Prof. Vasudevan’s technology involved adding melted plastic, which is less than 100 micron thickness, to the hot gravel prior to mixing it in bitumen. Now, plastic is the binder and prevents water seepage. According to him, roads with plastic can be laid in all weather and temperature conditions with minor adjustments to the percentage of bitumen and temperatures of components. To lay 1 km of road, one tonne of plastic is needed with nine tonnes of bitumen as opposed to 10 tonnes of bitumen, with the cost of one tonne estimated at ₹50,000.
This technology produces roads that are more than twice the strength of traditional roads and last longer as noted by the Indian Road Congress in 2013 which approves addition of plastic that is 5-10% the amount of bitumen. According to a Corporation official, the city’s roads are re-laid every five years but plastic roads can last up to 15 years. Professor Vasudevan’s technology also proves to be cost effective as less bitumen is required.
Despite these obvious benefits, the Greater Chennai Corporation has been lukewarm to the idea. The professor said during the late Chief Minister Jayalalitha’s tenure, the response was better. The State government has been proactive in banning single-use plastic and very recently seized 2,671 kg of banned plastic and collected ₹12,55,700 as fine. “This method requires shredded plastic of certain microns and indirectly, encourages the use of plastic which we want to curb,” says a corporation official terming the method as not being user-friendly.
The Corporation is currently undertaking projects to fix potholes across the city when a permanent fix like plastic roads is viable using seized or collected plastic waste.
Published - November 18, 2022 08:49 pm IST