Longfellow Bridge has concrete checkup

 State officials hope the Red Line travel on the Longfellow Bridge will be back to normal speeds by the end of the month.

But before that happens, crews have been testing certain areas of concrete supporting the bridge that hadn’t been previously inspected, at the request of the Federal Highway Administration.

The MBTA has slowed Red Line trains from 40 miles per hour to 10 miles per hour at the FHA’s recommendation, while lanes to cars and trucks have also been restricted in each direction. But the latest repair work, including the new concrete testing, should yield a new load rating for the bridge. That result should determine if the bridge can safely handle normal train speeds and traffic volumes.

The Boston Globe first reported the bridge’s latest concrete inspections Saturday.

The decades-old bridge — controlled by the state’s Department of Conservation & Recreation — was targeted for immediate inspections after a Minneapolis bridge collapsed in last August. It has undergone daily surveillance and numerous repairs since, and the number of repair crews was recently increased from one to five, with a sixth helping out on weekends.

But DCR Commissioner Richard Sullivan said the agency is taking the most conservative recommendation, “to inspect and test absolutely everything.”

“No one has seen anything in field that there is a problem with it,” Sullivan said yesterday, speaking about the concrete now being inspected.