Specials

Numerous advantages of building plastic roads

August 2019
India’s pothole menace has been a never-ending one, with the country reporting an increasing number of deaths year-after-year. Speaking of hazards, another is the modern-day problem of disposing plastic. Here’s a solution to tackle both these perils together: building plastic roads. Such roads not only prevent potholes but are eco-friendly and cheaper to build and maintain.

This technology was first used by Tyagraja College of Engineering in 2002 with a pilot inside the college campus. The technology is patented by TCE, Madurai, under the guidance of Dr R Vasudevan. Tata Steel’s Jamshedpur Utilities and Services Company (JUSCO) then got in touch with Prof Vasudevan in 2009, understood the process, reengineered it and implemented it, as per its own conditions and machineries. “We were the first to do it in eastern India, with a vision to replicate it further in other cities,” says Gaurav Anand, Chief Manager, Business Excellence, JUSCO.

The advantages
There is hardly any difference in constructing roads with this technology compared to conventional road construction methods. The mixing of shredded plastics is the only additional process. Yet, recycling plastic wastes by mixing them with bitumen can help build stronger, better quality roads at a cheaper cost.

“The technology is about utilising the lowest-end plastic waste, which hardly has any recycling value and would have otherwise polluted water bodies, choked the nallahs and killed animals if consumed by them,” highlights Anand. “The biggest advantage of plastic roads can be seen during the monsoon, when there is water-logging on the road and still no potholes are formed.” He elaborates that the main reason is that the aggregates used in this construction are pre-laminated or coated with plastics, which stops rainwater from percolate through, hence contributing to longevity. Besides, it ensures better quality, water-resistant, maintenance-friendly roads, among other benefits. In fact, its longevity is twice that of bitumen-only roads. Further, it is maintenance-free for the first five years.

Other qualities of plastic-tar roads include:

  • Strength of the road increases by 100 per cent (increased Marshall Stability Value)
  • Better resistance towards rainwater and water stagnation
  • No stripping and no potholes
  • Increased binding and better bonding of the mix
  • Increased load-withstanding property (withstanding increased load transport)
  • Consumption of bitumen decreases by not less than 10 per cent
  • Reduction in pores in aggregate and, hence, less rutting and ravelling
  • Better soundness
  • Maintenance cost of the road is almost nil
  • Road life is doubled
  • No leaching of plastics
  • No effect of radiation like UV.

Environmental benefits include:

  • The waste plastic is used only for the lamination of stone aggregate. There is no evolution of any gas during the process. There is no air or land pollution.
  • There is no evolution of CO2 (only melting of plastics).
  • If 1 km of single-lane plastic tar road is laid, 1 tonne of plastic is used; this helps avoid the evolution of 3 tonne of CO2, which may otherwise result owing to the burning of plastics.

Investment, cost and returns
There is no additional investment using this technology. In fact, there is a reduction in the cost and saving of bitumen. When comparing a road constructed with this technology, the cost is about Rs 50,000 less than a conventional road, considering the construction of a road surface area of 4,000 sq m, highlights Anand. Where 1 tonne of bitumen costs Rs 50,000, the same volume of waste plastic would cost Rs 10,000. About 10 per cent of bitumen can be substituted by plastic. When calculated, using plastic wastes would save about 1 tonne of bitumen or Rs 40,000 net for 1 km of a 4-m-wide road. Further, there is no maintenance expenditure for five years. The returns include a clean environment, free from plastic waste; better roads without any deformation from rain or traffic load; saving natural resources; and using plastic waste effectively in an eco-friendly manner.

SERAPHINA D’SOUZA