CINCINNATI — Tons of concrete and steel covered the southbound lanes of a major Cincinnati artery Tuesday after an overpass collapse during demolition work left one worker dead, a tractor-trailer driver injured and police considering what the potential toll might have been had the accident occurred amid heavy traffic.The removal of debris from Interstate 75 began Tuesday afternoon and was expected to take 24 to 48 hours. Ohio transportation authorities will then assess the pavement where the section of overpass deck landed Monday night with what a resident described as an earth-shaking thud. The Ohio Department of Transportation said it’s difficult to predict how long pavement repairs might take without seeing the damage.Cincinnati authorities said casualties could have been much higher had the accident occurred at a busy time on the interstate that carries more than 178,000 vehicles a day through the area some five miles north of the Ohio River.“The situation could have been significantly worse,” Cincinnati Police Chief Jeffrey Blackwell said Tuesday. “It’s just timing that we only had one fatality.”Authorities identified the worker who was killed as Brandon William Carl, 35, of Augusta, Kentucky. The Hamilton County coroner’s office will do an autopsy to determine cause of death; Cincinnati fire officials said the body was recovered from rubble with the help of air bags and special equipment early Tuesday morning, about four hours after the accident.