[Grarypealumma]

Will the difference be as stark as black and white? Forty bus routes in the city could go from broken-up, black back-breakers to reinforced, white-topped wonders that will make travelling through the city a breeze.

Chennai Corporation and the Cement Manufacturers' Association on Wednesday successfully conducted a white-topping experiment on one side of a stretch of Velachery Main Road, laying a concrete top on the existing thoroughfare to test its strength.

Corporation officials said a proposal to overlay 40 bus routes with white concrete would soon be placed before the civic body's council for approval. The move comes ahead of the northeast monsoon, which leaves roads in the city potholed and cracked every year.

A senior corporation official said the civic body plans to give a concrete top to 367 km of roads in the city at an estimated Rs 583 crore in 2012-2013. Several companies have expressed interest in the proposed project.

"We have conducted a test of the white-top technology on 700 metres of Velachery Main Road," a corporation official said. "If the corporation council approves the plan, we will use this technology on major bus routes." The white-top consists of a mix of fly ash, polymeric fibre, cement and sand. This composition offers much more durability than bitumen. The corporation will continue to use a plastic-bitumen mix for ongoing road work.

Experts said white-topping roads could increase their lifespan by 25 to 30 years with basic maintenance. They are also likely to be cost effective when compared to bitumen roads, which require frequent maintenance due to wear and tear and waterlogging. "The main advantage of the technology is that it can be used on existing bitumen roads by bonding without having to dig up the top layer," the corporation official said. A road engineer with a private firm said the civic body would need to coordinate with government departments and agencies, TNEB and Metrowater, and have adequate manpower at its disposal to implement the project ahead of the monsoon. "It takes nearly a month to lay 1 km of concrete road while bitumen roads can be completed within a week," he said. "But concrete roads reach 70% of its final strength in just seven days."

"We will come up with a comprehensive plan before white-topping the roads," the corporation official said. "After the roads are laid no digging will be allowed for any reason," The white-top technology is widely used in the United States and in European countries.

Source: Times of India