The Memorial Bridge closure, part of the more than two years of major construction that began this fall, is needed to install additional support under the middle span of the bridge as crews begin to remove rusted rebar and steel.

WASHINGTON — The Memorial Bridge will completely close from 9 p.m. Friday to 5 a.m. Monday, weather permitting.

The closure, part of the more than two years of major construction that began this fall, is needed to install additional support under the middle span of the bridge as crews begin to remove rusted rebar and steel.

The closure, which will block both vehicle traffic and people walking or biking, falls on the final scheduled weekend of Metro’s Yellow Line shutdown.

People who want to walk or bike across the river will need to go north to the Key Bridge or south to the 14th Street Bridge.

The closure could be postponed if there is bad weather.

At the end of the closure, the bridge is scheduled to return to its construction layout of three lanes and one sidewalk open, with the center lane of traffic reversing based on the time of day and day of the week.

Additional full weekend closures are planned at times for the next two and a half years. The next one is planned for January.