Bengaluru: Traffic congestion on Tumakuru Road is set to ease as the Peenya flyover will reopen for heavy vehicles at the end of July after nearly three years, officials said.
However, heavy vehicles will be prohibited from using the flyover once a week — from 6 am on Friday to 6 am on Saturday — to prevent vibrations during ongoing cement grouting works, they added.
The 15-metre-wide, 4.2-km-long flyover in northern Bengaluru has been closed to buses and trucks since December 2021 after prestressed cables in its three spans gave way due to corrosion. The corrosion was caused by the ingress of moisture and sunlight.
The closure has seriously affected vehicular movement on the road below, causing daily traffic jams.
In 2023, the National Highways Authority of India (NHAI) initiated a Rs 38.5-crore repair project to add two additional cables into extra slots at every span and stress them to strengthen the flyover. With 120 spans in the flyover, the NHAI has added 240 prestressed cables. The flyover passed load tests in January.
In addition, the NHAI is replacing 1,243 existing prestressed cables to prevent future corrosion, as recommended by a four-member expert committee.
The work involves de-destressing, removing and replacing the cables. In engineering, stress refers to the external force applied to an object.
KB Jayakumar, Project Director, NHAI, Bengaluru, told DH: "We will reopen the flyover for heavy vehicles sometime in the last week of July. We have submitted a report to the NHAI headquarters detailing the present site and traffic conditions, along with the recommendations of the expert committee and the traffic police. Approval is expected early next week. We will start allowing heavy vehicles within a day or two afterwards."
Prof Chandra Kishen JM of the Indian Institute of Science (IISc), who heads the expert committee, told this newspaper: "We have cleared the flyover for heavy loading because it has been fully strengthened. To facilitate grouting for strengthening the existing 1,243 cables, there should not be any vibration on the flyover for one day in a week."
Jayakumar said that the traffic police suggested banning heavy vehicles on Fridays, which usually see huge traffic as people head out of Bengaluru for the weekend. He added that grouting would take 14-15 hours and some additional time to set.
Joint Commissioner of Police (Traffic) MN Anucheth confirmed that the NHAI had asked for banning heavy vehicles for one every week.
Work is also underway to paint boards and prepare signage. The top speed on the flyover will be restricted to 40 kmph. Traffic police, equipped with speed radar guns, will be stationed on the truck lay-bye to enforce the speed limit, Jayakumar said.
According to Prof Kishen, the NHAI has so far replaced 260 cables in 26 of the 120 spans, with work ongoing in the remaining spans. This is a time-consuming process because cutting the existing tensioned cables with welders takes time.