The Park Street flyover in the heart of the city will be shut to traffic from 10pm on December 3 to 6am on December 6 for a load test of the structure.
Senior officials of the Hooghly River Bridge Commissioners (HRBC) — the agency responsible for the maintenance of the flyover — has informed police that personnel and machinery will move in from the morning of December 3 and the test will begin that night.
On December 4 and 5, engineers will conduct a series of tests on the 1.3-km flyover on Jawaharlal Nehru Road before it is opened to traffic on the morning of December 6, Monday.
The Park Street flyover will be the first among five flyovers, which HRBC maintains, that will undergo load tests over the next month-and-a-half. The four others are the Gariahat flyover, the AJC Bose Road flyover, the Lockgate flyover in Chitpore and the Nagerbazar flyover in Dum Dum.
“We have chosen a timeline that includes a Friday night, Saturday and Sunday for the test to be completed because the vehicular load is expected to be comparatively low during this time,” said a senior officer of Kolkata police.
“Since the flyover will be opened to traffic from 6am on Monday, we will try and ensure there is minimum traffic diversion when the flyover is closed.”
The Park Street flyover, with Lindsay Street and Middleton Street as its extremities, was inaugurated in February 2005 to ease the flow of traffic over the Park Street junction on Chowringhee Road.
HRBC engineers said while the traffic load on the flyover has gone up by several times over 15 years since then, there has not been any major overhauling of the structure apart from periodic maintenance.
“The steel and concrete structure needs immediate assessment of the extent of wear and tear it has undergone over all these years following sustained exposure to vehicular load,” said a senior engineer of the HRBC.
“We have engaged an agency to conduct the load test for us so that there is a clear assessment of the repair and maintenance work that may be required.”
Engineers will find out the horizontal pressure of wind that tries to push the bridge sideways, while in the dynamic test, the aim will be to measure how the bridge oscillates under the impact of the vertical wind pressure.
“The results will be collated and experts will analyse them to determine the structural stability of the bridge,” said a senior HRBC official.
Police officers said both Esplanade-bound and Exide-bound traffic will be diverted through JL Nehru Road.
In case of any emergency, a part of the Esplanade-bound traffic may be diverted down Red Road from the Park Street crossing. Similarly, if required, the Exide-bound traffic may be diverted down Dufferin Road and Mayo Road via RR Avenue.