Here are a few images from photographer Gary Leonard’s pictorial on how the south half of the Mulholland Bridge came down the weekend of July 15 to 17. Above is a shot showing what the bridge looked like last Friday afternoon.
The demolition began the evening of Friday, July 15, when work crews began closing freeway on- and off-ramps.
Two very large light plants and some 12 regular light plants turn night into day in the area surrounding the Mulholland Bridge.
At midnight Friday, trucks began to haul dirt onto the 405 under the Mulholland bridge to form a cushion four feet high to prevent damage to the freeway lanes from falling debris and chunks of concrete.
Work crews use a large diamond-blade sawto cut the top deck and soffit of the bridge. Workers cut slots in the southern side of the bridge to quicken the demolition process.
Giant “hoe rams” chip away at the south side of the bridge. These powerful demolition machines deliver between 1,200 and 7,500 foot-pounds of power to break away the concrete. (Hand-held jackhammers deliver 90 foot-pounds of power.) Operators deliver between 300 and 600 blows per minute to break the deck into pieces the size of a basketball. Later, the concrete will be pulverized and recycled.
Workers use long-handled oxygen/acetylene torches to cut the steel rebar from the deck. Workers are tied to a secure anchor and wear fall protection equipment as they work. The rebar will be recycled.
Front-end loaders are used to load debris from demolition into large trucks to be hauled away for recycling.
Work crews thoroughly clean and inspect the edge of the bridge to make sure no particles remain. Street sweepers clean the freeway surface under the bridge.
Mayor Villaraigosa and public safety officials hold a news conference in the media camp to announce the opening of the I-405 on Sunday at noon, one day early.
The CHP escorts traffic back onto the newly reopened 10-mile stretch of the I-405 freeway.
Categories: I-405 closure July16-17, Projects