Wirtgen Cold Milling: Doing it the Right Way

City Milling in India, Hyderabad: Cost Effective, Eco-friendly and Speedy

Hyderabad, the capital city of Telangana, has a well-developed road network of around 9000 Kms maintained by the Greater Hyderabad Municipal Corporation (GHMC). 2900 Kms out of this road network are bituminous roads varying from single lane to four lane design. Over the years, the life of these pavements has reduced due to various factors like ageing, monsoon damages, heavy loading, etc. which then called for maintenance and recarpeting of these roads.

Identifying the constraints

Due to frequent recarpeting without removal of the underneath damage, the quality of the bituminous recarpeting was not up to the mark which results into the reappearance of the damages, potholes, and other distresses underneath.

The road levels had also increased as compared to the levels of adjacent residential and commercial setups resulting in flooding of these areas during monsoon due to the disturbance in the drainage design of the city.

“It is a right step taken up by GHMC to incorporate Cold Milling as a standard practice in all the maintenance tenders under CRMP. The overall quality of the pavement has been better by implementing Milling. The final surface looks very even and smooth with perfect slope ensuring proper flow of rainwater into the drains. We are thankful to the Wirtgen Group – for supporting us with such high performing Cold Milling machines.”

Mr. V. Narasimha Ramana, Sr. Vice President (Tech), KNR Constructions Ltd.

Doing it the right way Using Cold Milling technology

Since 2019, the GHMC has come up with a Comprehensive Road Maintenance Program (CRMP) to improve the maintenance of roads in the city. Under the CRMP, GHMC has entrusted repairs, maintenance, and re-carpeting of 709 km of roads across the city.

To ensure high quality pavement, even profile, smooth surface and to maintain the road levels, GHMC has mandated the use of Cold Milling technology in all the road maintenance packages to remove the existing damaged top-layer of the pavement before going for bituminous resurfacing.

Cold milling machines are used to remove asphalt and concrete surfaces quickly and efficiently. In doing so, they create a level foundation with the specified width and depth that is required for paving new surface layers of uniform thickness.

By implementing Cold Milling, GHMC has ensured that the recarpeting of the city roads is of highest quality and the road levels throughout the city are not raised any further. The compact design of the Milling machines allows lane by lane operation without creating any traffic hindrance. The simultaneous Milling and loading of RAP material through belt conveyor and smooth milled surface facilitated efficient traffic management on the adjacent lane during Milling.

This ensures the quick completion of road rehabilitation and minimizing the traffic obstructions.

“Milling and filling is the right approach for any road maintenance by which we were able to maintain the road levels and remove the distressed pavement as well. The precision and accuracy of the Milling was very high, resulting in an even surface ready for paving. Also, the process is extremely fast with minimal disruption to traffic, allowing us to finish the job in less time. GHMC has taken a right step and we hope the practice continues in other cities as well.”

Mr. Sandeep B.- Director, BSCPL Infrastructure Ltd.

Proud to be a partner

The Milling process is being carried out using Wirtgen’s fleet of 7 Cold Milling machines – The compact 1m class W 100 H is especially designed for city roads, and the high performing 1.3m class W 130 CF and the advanced and cost efficient 2m class W 195 are in continuous operations in various parts of Hyderabad city. The Milling process was followed by a smooth and even surface course overlay.

The Milling machines are operating from a depth of 40mm to 100mm in Hyderabad; however, they are capable of Milling up to a maximum depth of 330mm. The high performing machines produce an output of 400 to 1200 m² per hour. The LED light setup assists in hassle free operation at night. The German-engineered design of ‘Milling housing and sprinkling system’ ensures negligible sound and air pollution, thereby causing minimal disturbance to the nearby setups unlike conventional pavement dismantling methods.

“Milling and filling is the right road maintenance technique by which the road levels can be maintained, and distressed pavement be removed. This is rapid process with minimal disruption to traffic, allowing us to finish the job in time.”

Mr. LB Nagar Zone the Superintending Engineer, GHMC