BALTIMORE– After weeks of preparation, crews are scheduled to perform a controlled demolition Sunday night to break the largest remaining span of Maryland’s Francis Scott Key Bridge, which collapsed under the impact of a massive container ship on March 26.
The steel span – which is about 500 feet (152 meters) long and weighs up to 600 tons (544 metric tons) – came to rest on the ship’s bow after the Dali lost power and collided with one of the bridge’s support columns shortly after. after leaving Baltimore. . The ship has since been trapped among the wreckage and the busy port of Baltimore has been closed to most maritime traffic.
Six members of a road works crew died in the collapse. The last of their bodies was recovered from the underwater wreckage earlier this week. All of the victims were Latino immigrants who came to the U.S. seeking employment opportunities. They were filling potholes during the night shift when the bridge was destroyed.
The controlled demolition will allow the Dali to be refloated and guided back to Baltimore Harbor. Once the ship is removed, maritime traffic could begin to return to normal, which will provide relief to thousands of dockworkers, truck drivers and small business owners who saw their jobs impacted by the closure.
The Dali’s 21-member crew will shelter aboard the ship while the explosives are detonated.
William Marks, a spokesman for the crew, said they would shelter “in a designated safe location” during the demolition. “Every precaution is being taken to ensure everyone’s safety,” he said in an email.
Officials said demolition is the safest and most efficient way to remove steel under high levels of pressure and stress.
“It is unsafe for workers to be in the immediate vicinity of the bridge frame for final cuts,” officials said in a news release Sunday.
In a video graphic released this week, authorities said engineers are using precision cuts to control how the trusses come apart. They said the method allows for “surgical precision” and that the steel structure will be “pushed away from the Dali” when the explosives cause it to fall into the water.
Once demolished, hydraulic grabs will lift the resulting steel sections onto barges.
“It is important to note that this controlled demolition is not like what you would see in a movie,” the video says, noting that from a distance it will sound like fireworks or loud thunder and emit clouds of smoke.
So far, about 6,000 tons (5,443 metric tons) of steel and concrete have been removed from the collapse site. Authorities estimate the total amount of debris at 50,000 tons (45,359 metric tons), approximately the equivalent of 3,800 loaded dump trucks.
Authorities previously said they hoped to remove the Dali by May 10 and reopen the port’s 15.2-meter main channel by the end of May.
The Dali is scheduled to be refloated during high tide on Tuesday, officials said Sunday. They said three or four tugboats will be used to guide the ship to a nearby terminal at the Port of Baltimore. She will likely remain there for a few weeks and undergo temporary repairs before being transferred to a shipyard for more substantial repairs.
Dali’s crew have not been allowed to leave the stranded vessel since the disaster. Authorities said they are busy maintaining the ship and assisting investigators. Of the crew, 20 are from India and one is from Sri Lanka.
The National Transportation Safety Board and the FBI are conducting investigations into the bridge collapse.
Danish shipping giant Maersk chartered the Dali for a planned voyage from Baltimore to Sri Lanka, but the ship didn’t go very far. Her crew sent a distress call saying she had lost power and had no control of the steering system. Minutes later, the ship crashed into the bridge.
Officials said the safety board’s investigation will focus on the ship’s electrical system.
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