KOCHI: ‘White topping’ technology can fix the city’s potholes-ridden roads and solve commuters’ travelling woes all at once, former Central Public Works Department chief engineer and technical advisor to INKEL Jose Kurian said on Thursday. “Excessive rain is a major reason for the bad condition of roads in Kochi and the state. Water is the enemy of asphalt roads. Such roads last two to three years before requiring resurfacing works,” he told reporters while elaborating on the technology which guarantees smooth road surface for at least 20 years.
White topping involves laying a layer of pavement quality cement (PQC) over the existing asphalt pavement after drilling it. The cement cover can be laid using a normal paving machine.
“Unlike asphalt, cement loves water. Hence, the road surface doesn’t break due to heavy rain or flooding. The thickness of M40-grade PQC on the road can be around 100mm-300mm, depending on the traffic and types of vehicles plying on it,” Kurian said.
“It usually takes around 14 days for the cement to fix completely. However, using the technology, the work can be completed in seven days. If initial issues are not taken into consideration, people will have a permanent solution to their travelling woes,” he said.
Higher cost
‘White topping’ a road costs 30 per cent higher than the cost of laying an asphalt road. Constructing a 1-km-long and 8-m-wide stretch of a road using the technology costs `1.3 crore.“The concrete overlays will have lesser pavement deflection resulting in reduced vehicle fuel consumption. It will also reduce vehicle emissions. Road visibility even at low light will be higher on PQC roads. With better visibility, braking distance of vehicles will come down in wet and dry conditions,” he said.
“Unlike asphalt roads, concrete overlays can also be recycled. The cement content can be reduced by 50 per cent using GCBS or fly ash. On both sides of the road, tiles are paved to ease any pipe repair work. Service ducts will be available below the roads to allow cables and pipelines,” Kurian said.
In Kochi, the road stretch from HMT Junction to Manalimukku was laid using white topping technology. Four years since the construction of the 5-km road was completed, no potholes or damage have been reported till now. “The first PQC road was constructed in Pune around 10 years back. White topping work of national highways is over in Bengaluru. Our Public Works minister had visited the NH in Bengaluru and expressed interest to introduce the same technology here,” he said.