A quick fix for cratered city roads is on the way in the form of two truck-mounted pothole repairing machines that can complete in five minutes what a contingent of workers usually needs more than 30 minutes to do.
A road can be reopened to traffic almost immediately after the potholes are filled, unlike when manual repairs are carried out. Just a 15-minute gap between two spells of rain will enable a machine to fix several potholes on the same stretch, something that is almost impossible for workers to do manually.
An engineer in the Calcutta Municipal Corporation (CMC) said the machines being considered for purchase were capable of doing the entire job without intervention – from cleaning a pothole, filling it with hot mix and smoothing out the surface to make it ready for traffic. A driver, an operator and a helper accompany each truck-mounted machine.
An official at Speedcrafts, a company that manufactures pothole repairing machines, said each of them can fill about 20 potholes of large size in a day, which translates into a road length of around 5km.
“The first step is cleaning. Air is blown at a very high velocity of 320kmph to remove any debris or loose particles,” said M.J. Jafri, senior general manager of the company.
In the next step, an emulsion is discharged into the pothole. In engineering parlance, it is called a tack coat and this emulsion acts like an adhesive that helps absorb the filling.
“After the tack coat is poured, the filling material is discharged at a velocity of nearly 115kmph to ensure that the filling reaches all corners of the pothole,” Jafri said.
The stipulated velocity also ensures compaction.
The moment the pothole is filled and its top reaches the height of the surrounding road surface, work is stopped. “There is no need to keep the just repaired pothole barricaded, unlike in manual repairs. Vehicles can immediately run above it,” a CMC engineer said.
Another advantage of a pothole repairing machine is that it can repair roads even on days when it is raining. Manual repairs are not possible on a rainy day because the entire process takes a lot more time. Rain also washes away the bitumen if it doesn’t get enough time to dry.
Officials at Speedcrafts, which is headquartered in Patna , said they had supplied pothole repairing machines to the Jalgaon City Municipal Corporation in Maharashtra and the Border Roads Organisation, among others.
The company had given a demonstration of how the machine works to the CMC around two years ago.
The tender floated by the CMC mentions a budget of Rs 3.4 crore for two machines. The time for completing the order is four months. “This is only an estimate, though. The actual procurement cost can be lower,” a municipal official said.
Source: The Telegraph