New technology paves way for a smoother ride

Mandakini Gahlot takes a look at the technology used in laying and resurfacing roads in the Capital

The Public Works Department (PWD) has introduced at least three new technologies over the last year to repair damaged roads and build new ones. But with all attention focused on roads linked to the Commonwealth Games projects, Delhi continues to be riddled with potholes.

Recycling (In-situ)
Conventionally, a new layer of asphalt is deposited on the road each time it is resurfaced. That increases the level of the road. In recycling, the top layer of asphalt on the road is removed, which is mixed with fresh bitumen and then laid on to the road. “Nearly 70 per cent of the material is recovered and only 30 per cent fresh bitumen is added,” said K K Sharma, Secretary PWD, “it is an environment friendly method”. Roads fixed this way have a lifespan of five to seven years. Plus, they dry fast and can be used within hours. Sharma said the PWD has sanctioned Rs 90 crore for repairing roads through this technology and work is underway on Ring Road from South Extension to Dhaula Kuan and Africa Avenue, among others.
The PWD has set a June 2010 deadline for 23.69 km of roads. The stretches include the road from Old Seemapuri to Swami Dayanand Marg, Maujpur to Deputy Commissioner's Office, Loni flyover to Bhopura Road and Wazirabad Road, Apsara border to Ghazipur crossing, UP Link road to Club Road, and Dallupura to Vasundhara Enclave.

Waste plastic technology
With this method, the Delhi government hopes to kill two birds with one stone — reuse burgeoning plastic waste and repair bad roads. Plastic waste is shredded and mixed with bitumen to yield a compound called polymerised bitumen, which is used for surfacing. Roads built with this suffer less damage during monsoons. They cost around 5 per cent more than conventional technology, but last longer. The PWD intends to resurface 242 km this way by June 2010 — the cost will be Rs 250 crore. Work is underway on 71 kms in South Delhi and 32 kms in East Delhi. The stretches include the airport area, Rama Road, Aruna Asaf Ali Marg, IGP Slip Road, Bhairon Marg, Okhla Estate Marg no-13, Bhakti Vedanta Marg, and Anuvrat Marg.

Micro-Surfacing
In this method, cracks in roads are filled and resurfaced with a mixture of fine stone aggregates and cold bitumen emulsion. This is ideal for roads in which the wear and tear does not demand a complete resurfacing. By January 2010, the PWD intends to complete work on 16.81 kms of roads in East Delhi at a cost of Rs 7.25 crore using this technology. These roads include Road No 57, 57A, 58, 69, 70, 65, ITO Chungi, ITO to Karkari Mor, and Zafrabad to Keshav Chowk. Works is underway on 71 km in South Delhi and 32 km in East Delhi, where a mixture of waste plastic technology and micro surfacing is being used.