Road repair : Drigh Road flyover undergoes repairs for the 22nd time
The Drigh Road Bridge is undergoing repairs for the 22nd time after cracks emerged on one portion on Monday. The bridge connects Shahrae Faisal to Drigh Road for the traffic coming towards the airport and going to Gulshan-e-Iqbal.
The work is expected to be completed by Tuesday morning. Till then it has been closed for traffic. Workers are digging up the cracked portion to replace the steel fencing beneath the asphalt.
According to the director of technical services at Karachi Metropolitan Corporation (KMC), Altaf G Memon, the bridge was built in 2000. Since then it has been repaired more than 21 times, the highest for any bridge in Karachi. “But people don’t need to worry. It is not dangerous,” he said. “Only a deck slab has to be replaced. Otherwise it is all good.”
But Memon admitted that KMC’s engineering consultants had already found faults in the bridge’s design. “That does not mean that the bridge has to be torn down completely and rebuilt. We are trying to fix it.”
The deck slabs are made of steel mesh and concrete. When a bridge is built, the deck slabs are put together on the girders.
According to Memon, it wasn’t the flow of heavy traffic that damaged the bridge repeatedly. He said that the bridge could bear the weight of trucks.
However, the KMC engineers differed. “This bridge was not designed for heavy traffic in the first place,” said one of them. “Trucks weighing around 60 tons pass through this bridge. Imagine the load that the bridge has to withstand.”
Drigh Road Bridge was the first flyover to come under scrutiny after the Shershah Bridge collapsed in 2007 and the defunct city government carried out safety checks. The authorities had even considered moving it since it was also dangerous for traffic at Shahrae Faisal because the turn to the bridge is pretty steep.
Published in The Express Tribune, May 1st, 2012.
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Florida Department of transport after extensive study found that high strength PP fibers can reduce cracks in the bridge deck. To promote use of fiber in concrete, we started local manufacturing and marketing of this simple concept.