Lifting 5 million pounds of steel and concrete will take brute strength, gravity-defying force and a whole lot of muscle.

Or, 50 workers, 24 hydraulic jacks and a computer.

Starting Saturday night, routes will be closed so work crews can begin hoisting the flyover ramp that connects southbound University Drive with eastbound Interstate 595 as part of a $1.8 billion makeover to the main east-west corridor through Central Broward County.

And 24 hours later — by midnight Sunday when most routes will reopen — the bridge will be 18 inches higher.

The flyover project is just one piece of the Florida Department of Transportation’s I-595 Express Corridor Improvements Project, which involves widening the highway to ease the flow of the 180,000 vehicles that travel on it every day. The complex renovation includes adding new lanes, creating on- and off-ramps, and installing lighting along the 13-mile corridor.

By moving the flyover, additional space will be created for more travel lanes.

“We have to raise up the bridge to meet the minimum vertical clearance [for trucks] and shift it to the south to get enough room to get those lanes underneath it,” said Paul Lampley, the I-595 construction project manager. “It is a much more effective and efficient way to move traffic.”

Currently, drivers heading east are travelling on what will become three reversible express lanes: During the morning rush hour, those lanes will head east; during the evening rush hour, they’ll head west.

The flyover has to be lifted and lengthened to make space underneath it for five new lanes — including an exit-only to Davie Road — that will be built next to the three existing lanes.

Lampley explained that creating three reversible lanes will help the flow of traffic at its busiest times in either direction. This will reduce congestion on the road and speed up travel times.

“We really need additional capacity,” he said. “The concept will allow us to provide for that additional volume.’’

The entire construction project began in February 2010 and should be complete by summer 2014. The $1.8 billion price tag includes operation and maintenance of the highway until 2044.

Lampley said the original plan for the eastbound and westbound flyovers at University Drive was to take them down and rebuild brand new ones. But the new plan enables engineers to salvage the current ones and make adjustments to them. Not only does this plan reduce the inconvenience to the public, he said, using existing infrastructure throughout the I-595 project has already shaved about $200 million off the cost.

During this weekend’s project, the bridge will first be raised an eighth of an inch to make sure everything is functioning properly. Shims, or spacers, will then be inserted and pinned into place to fill each one-inch gap.

Once the bridge is raised Sunday night, traffic will be reopened on University Drive and the highway, but the eastbound flyover will remain closed until November.

Commuters will still be able to get on westbound I-595 while driving north or south on University Drive, and eastbound I-595 from northbound University Drive.

During the 120 days the eastbound ramp from southbound University is closed, crews will install new bolsters, bearings and reinforcing steel around each column. They will also begin to remove the southernmost 251 feet of the ramp, which will take about seven weeks to complete. This involves removing the surface, disassembling the steel support beams and destroying the southernmost column and foundation.