On Friday night, the MBTA demolished a 102-year-old bridge that carries Red Line trains over Clayton Street in Dorchester and less than 24 hours later had its replacement moving into position.
The MBTA was attempting an Accelerated Bridge Construction project for the first time on a subway line this Veteran’s Day weekend.
It set out to replace the overpass near Fields Corner in just 56 hours and have trains running again Monday morning.
The old bridge had been in need of extensive repairs.
“There were little metal sticks, pylons, holding the bridge up and it had been dented on multiple occasions by cars,” said Secretary of Transportation Rich Davey, who came to watch the work Saturday.
The transportation department has performed accelerated projects a handful of times before, but never on a subway line, he said.
The bridge brought in to replace the old one weighs 140 tons and measures 60 by 40 feet.
Buses replaced train service along a section of the route over the weekend as the work was done.
When the sun went down Saturday and the sky turned dark blue, floodlights were switched on and work on the span continued with the thrum of generators and the chattering of jackhammers. Residents of the neighborhood walked over to watch.
Davey took out his iPhone and bounced in place as an engineer with a joystick guided two huge red rolling platforms bearing the bridge down Clayton Street.
“I played with Legos growing up, this kind of thing brings out the little boy, the little girl in everybody,” he said.
Davey said officials plan to use accelerated timelines more often when possible in the future, though it’s not always feasible with historic structures or spans over wide waterways.
Nearby residents heard about the project months ago at neighborhood meetings, when transportation officials announced their plans to replace the bridge over a long weekend in the fall.
“It does seem like a lot to do, especially putting the tracks back on,” said Tom Hunt, 62, as sparks flew from a construction worker’s blowtorch.
A typical phased building project would have taken 30 months, according to the
“This would be more like ripping the Band-Aid off, get it over quickly,” Hunt said.
Tom Murphy, 49, said the noise over the weekend was not a problem half a block down the road where he lives.
“Only a couple of days, it’s not a big deal,” Murphy said.
But Paula Beckerman, 53, who lives almost directly under the bridge, said she hardly slept Friday night as machines droned and picked away at the old overpass.
As workers prepared to set the new structure into place late Saturday, Beckerman watched and admitted that despite the noise, the project was somewhat amazing.
“I just hope the bridge fits,” she said.Zachary T. Sampson can be reached at zachary.sampson@ globe.com.